CAD for simple 3-D metal & wood projects?

On 11/27/2013 8:31 AM, [email protected] wrote:
> On Tue, 26 Nov 2013 08:26:27 -0600, Leon <lcb11211@swbelldotnet>
>>> Anyway, I'll try again later in the day.
>> I did not change my address, replace dot with "."
>
> Between the mortises, rabbets and Domino joinery, I don't know if I'd
> have the patience to build the way you do. I guess once you develop
> the system and get in the habit of using it, the rest just comes
> naturally. It looks good and it's solidly built. I sure hope your
> customers appreciate the quality of the products they get from you.
> The everyday furniture I see up here is absolute junk compared to what
> you build. Maybe I need to visit some good quality cabinet builders.
>
> Was the dado extender jig, the one with the picture that had the Kreg
> joinery? If you can email me If so, I wouldn't mind some additional
> explanation. I have your proper email address and I've emailed you in
> the past, but right now I still can't email you directly. If you can
> email me, I'd appreciate it.
>
> Thanks
>


Seriously All of those joints are pretty simple with the Domino. You
just have to keep your shit together so that you don't screw up. ;~)

If anyone is going to screw up it would be me but so far after making
dozens of these face frames, no problems.

The back face frames are simple, I cut the dado's and or groves first.
Then I cut the rabbets that receive the back panels and form the joints
between the rails and stiles. The trick here is to cut the mating tenon
after cutting the rabbet with out moving your fence. The spacing for
the width of the rabbit is the same for the tenon. To cut the mating
tenon to fit the rabbet I simply mount my miter gauge and use the fence
as the stop for the length. All you have to change is the height of the
cut and I use a scrap to sneak up on that.

The trick to the Domino tenons is to simply dry fit the face frame after
all cuts have been made and mark the domino locations just like you
would with biscuits.

I use the tight fit setting on the Domino to cut the mortises on all
pieces that get the mortise in the end of the board. I use the middle
width setting on all of the pieces that receive the mortise on the edge
of the board. This gives me wiggle room.

A hint here, the 5 mm bit affords you the best fit when you only have
the 1/2" left over area under the rabbit. Also remember to reference
the same face when that you marked. don't turn the piece over so that
you can see what you are doing. ;~) The trick here is to remember to
make the Domino plunge and additional 12 mm to the normal 15 mm when
using the 5 mm x 30 mm domino. so that setting should be 27 mm. this
lets the bit cut 15 mm deep although it had to extend 12mm to start with
to cleat the edge of the rabbet and or tenon.

Clear as mud so far? ;~)

Anyway you would think that this would be difficult but I have not yet
had a miss fit.


Now if you have not guessed yet the front face frames and back face
frames dado's/groves have to mirror each other where the bottom, top and
side panels fit. During the cutting operation for the back and front
face frames it is critical that the back face frame pieces that receive
the tenon to fit the rabbet be "1 inch" longer than the same front face
frame parts. Remember that the tenon is 1/2" longer on each end for the
back face frame.

Any way after every thing is glued up you will notice that that the
groove/dado in the bottom/top rails butt up against the outer stiles.
This dado needs to extend to the dado in the stile. Cutting that short
distance across the outer stile needs to be done free hand so to speak.
Not a problem on the front face frame as it is not easily seen when
you look in the cabinet. The back face frame is another matter
altogether, you see that cut when you look inside the cabinet.
The dado jig in the picture makes completing that dado simple and fast
for both front and back face frames.

I sent you an e-mail using the address you used last year so you should
be able to return my e-mail for details if you want.

On Tue, 26 Nov 2013 08:26:27 -0600, Leon <lcb11211@swbelldotnet>
>> Anyway, I'll try again later in the day.
>I did not change my address, replace dot with "."

Between the mortises, rabbets and Domino joinery, I don't know if I'd
have the patience to build the way you do. I guess once you develop
the system and get in the habit of using it, the rest just comes
naturally. It looks good and it's solidly built. I sure hope your
customers appreciate the quality of the products they get from you.
The everyday furniture I see up here is absolute junk compared to what
you build. Maybe I need to visit some good quality cabinet builders.

Was the dado extender jig, the one with the picture that had the Kreg
joinery? If you can email me If so, I wouldn't mind some additional
explanation. I have your proper email address and I've emailed you in
the past, but right now I still can't email you directly. If you can
email me, I'd appreciate it.

Thanks

"Lloyd E. Sponenburgh" <lloydspinsidemindspring.com> on Mon, 25 Nov
2013 11:49:47 -0600 typed in rec.crafts.metalworking the following:
>Leon <lcb11211@swbelldotnet> fired this volley in
>news:[email protected]:
>
>> I am a woodworker and routinely work with pieces that measure in 1/8"
>> resolution however the program is quite capable of accurately and quite
>> quickly drawing a box that is 4 1/16 x 5 3/64 x 9 19/32.
>
>If I were using it for woodworking, I assume those accuracies would be
>adequate, if a little gross for a CNC router...
>
>But I work daily with sub-thousandth measurements. Do you really
>understand how funny dealing with "thirty-secondths" sounds to a
>metalworker?

As the watchmaker's apprentice said when seeing a 1/4-28 tap "My
God, I didn't know they made them that big!"
--
pyotr filipivich
"With Age comes Wisdom. Although more often, Age travels alone."

On Mon, 25 Nov 2013 09:24:59 -0600, jim <"sjedgingN0Sp"@[email protected]>
wrote:

>
>
>[email protected] wrote:
>>
>> On Sun, 24 Nov 2013 18:22:26 -0600, jim <"sjedgingN0Sp"@[email protected]>
>> wrote:
>>
>> >
>> >
>> >[email protected] wrote:
>> >>
>> >> On Sun, 24 Nov 2013 17:08:14 -0600, jim <"sjedgingN0Sp"@[email protected]>
>> >> wrote:
>> >>
>> >> >
>> >> >
>> >> >[email protected] wrote:
>> >> >
>> >> >> >
>> >> >> >People have been making things flat or round to that level of
>> >> >> >precision for ages.
>> >> >>
>> >> >> Flat and round (spherical) are trivial problems and as you note it's
>> >> >> been done for ages, at least since the middle ages.
>> >> >
>> >> >And there isn't much advantage in having a
>> >> >CAD model for those shapes.
>> >>
>> >> There isn't much reason to have a CAD model for a board, either, but
>> >> when you want to put a few dozen of them together, having a CAD model
>> >> gets rather interesting.
>> >> >
>> >> >
>> >> >> Other shapes are
>> >> >> more difficult, as is size.
>> >> >
>> >> >And it is doubtful there is anyone reading this who
>> >> >is cutting complex shapes from CAD models with precision
>> >> >held to tenths.
>> >>
>> >> Huh??? Have you ever heard of a mirror, or lens, system? Please
>> >> explain your statement?
>> >
>> >How many have you modeled in CAD and then manufactured
>> >to within tenth of the designed part?
>>
>> You still make no sense. Are you saying that precision machining
>> doesn't require the same level of modeling that sloppier work does?
>> Really?
>
>First of all most of the examples of precision that have
>been given involve no 3d modeling at all. And the rest
>appear to be at best 2d modeling (e.g.. a lathe profile).

Ah, so neither Boeing or GE use 3-D modeling to design airplanes or
engines. They hand draw anything that requires precision. Got it.

>I'm saying that any CAD system can produce geometry that
>is far more accurate than any manufacturing process. If a 3d
>computer model has dimensions that are different than what you
>like them to be, it is because of the input the software was
>given, not because the software is sloppy.
>
> A program like Sketchup caters to people who want to
>model something that looks good without paying much attention
>precise numbers. But that doesn't mean it is sloppy. It just
>means it is not as easy to hit the exact numbers you may want as
>in other programs that cater to people who want models driven
>by precise numerical inputs instead of mouse actions.

Absurd. You *clearly* don't have a clue.

On Mon, 25 Nov 2013 11:00:11 -0600, Leon <lcb11211@swbelldotnet>
wrote:

>I am a woodworker and routinely work with pieces that measure in 1/8"
>resolution

Oh..you work to .125 tolerances then?


__
"A human being should be able to change a diaper, plan an invasion,
butcher a hog, conn a ship, design a building, write a sonnet,
balance accounts, build a wall, set a bone, comfort the dying,
take orders, give orders, cooperate, act alone, solve equations,
analyze a new problem, pitch manure, program a computer,
cook a tasty meal, fight efficiently, die gallantly. Specialization is for insects."
- Heinlein

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On Mon, 25 Nov 2013 12:43:14 -0500, "Jim Wilkins"
<[email protected]> wrote:

>You are demonstrating my point that petulant misfits will snatch at
>any excuse to belittle capable people.

You powers of perception is great, you can and do read way more than
is said.

On 11/25/2013 12:25 PM, Gunner Asch wrote:
> On Mon, 25 Nov 2013 11:00:11 -0600, Leon <lcb11211@swbelldotnet>
> wrote:
>
>> I am a woodworker and routinely work with pieces that measure in 1/8"
>> resolution
>
> Oh..you work to .125 tolerances then?
>
>

No, that is not what I said, I said I routinely work with pieces that
measure in 1/8" resolution. The tolerances have to be much greater for
a joint to disappear.

There is a difference between resolution and tolerance. They are not
the same. I simply choose to design using 1/8" as my smallest
increment. The cuts have to be as close to that measurement as
possible. A piece that calls to be 48.125" needs to be as close to that
as possible. 48.120" is way not close enough if you don't want the
joint to stick out like a sore thumb.

Then stack on top of that the wood greatly changes shape, relative to
steel, depending on the relative humidity and a project may have several
hundred pieces that interlock with each other. We wood workers work in
pretty tight tolerances too but don't draw project pieces to sizes that
include minute fractions for the sake of having odd lengths and widths.
I realize this is required in smaller sized metal working projects
where size dictates higher precision.










> __
> "A human being should be able to change a diaper, plan an invasion,
> butcher a hog, conn a ship, design a building, write a sonnet,
> balance accounts, build a wall, set a bone, comfort the dying,
> take orders, give orders, cooperate, act alone, solve equations,
> analyze a new problem, pitch manure, program a computer,
> cook a tasty meal, fight efficiently, die gallantly. Specialization is for insects."
> - Heinlein
>
> ---
> This email is free from viruses and malware because avast! Antivirus protection is active.
> http://www.avast.com
>

On 11/25/2013 12:25 PM, Gunner Asch wrote:
> On Mon, 25 Nov 2013 11:00:11 -0600, Leon <lcb11211@swbelldotnet>
> wrote:
>
>> I am a woodworker and routinely work with pieces that measure in 1/8"
>> resolution
>
> Oh..you work to .125 tolerances then?

When "woodworking", depends upon what you're making/measuring.

In a construction project, .0125" is generally what a framing carpenter
shoots for when measuring for a cut.

Whereas a trim carpenter would probably base most of his measurements on
.03125".

In a piece of fine furniture or cabinetry, .015625" is often not
acceptable due to its obvious visibility, or when needing parts to be
square.

Leon, being a master craftsman, more than likely sets his drawing
"precision" for critical projects when using SketchUp to 1/64", which
gives you a roundup of 1/32" for cutting dimensions on a shop drawings.

That said, most learn quickly to batch cut like parts so that any error
in like components still make for consistent, same size parts.

--
eWoodShop: www.eWoodShop.com
Wood Shop: www.e-WoodShop.net
google.com/+KarlCaillouet
http://www.custommade.com/by/ewoodshop/
KarlCaillouet@ (the obvious)

"Markem" <[email protected]> wrote in message
news:[email protected]...
> On Mon, 25 Nov 2013 12:43:14 -0500, "Jim Wilkins"
> <[email protected]> wrote:
>
>>You are demonstrating my point that petulant misfits will snatch at
>>any excuse to belittle capable people.
>
> You powers of perception is great, you can and do read way more than
> is said.

I didn't mean you, but if the shoe fits...

"Leon" <lcb11211@swbelldotnet> wrote in message
news:[email protected]...
> On 11/25/2013 12:25 PM, Gunner Asch wrote:
>> On Mon, 25 Nov 2013 11:00:11 -0600, Leon <lcb11211@swbelldotnet>
>> wrote:
>>
>>> I am a woodworker and routinely work with pieces that measure in
>>> 1/8"
>>> resolution
>>
>> Oh..you work to .125 tolerances then?
>
> No, that is not what I said, I said I routinely work with pieces
> that measure in 1/8" resolution. The tolerances have to be much
> greater for a joint to disappear.
>
> There is a difference between resolution and tolerance. They are
> not the same. I simply choose to design using 1/8" as my smallest
> increment. The cuts have to be as close to that measurement as
> possible. A piece that calls to be 48.125" needs to be as close to
> that as possible. 48.120" is way not close enough if you don't want
> the joint to stick out like a sore thumb.
>

http://en.wikipedia.org/wiki/Granularity

For my circuit board layouts granularity was the snap-to grid spacing,
usually 0.010" or 0.0125" which are 1/100 or 1/80 of an inch.

The resolution was usually 0.002", the size step between track widths
and pad diameters.

The accuracy of the CAD data was 1 micron.

The tolerance was defined as how much larger a pad must be than the
hole drilled through it, to ensure that the drilled hole didn't break
through the outer circumference. IOW it was the allowable
misregistration between the etched copper circuit and the drill
machine. It was a manufacturing constraint, not a designer's choice.

jsw

On 11/25/2013 9:34 AM, Lloyd E. Sponenburgh wrote:
> jim <"sjedgingN0Sp"@[email protected]> fired this volley in
> news:[email protected]:
>
>> But that doesn't mean it is sloppy. It just
>> means it is not as easy to hit the exact numbers you may want as
>> in other programs that cater to people who want models driven
>> by precise numerical inputs instead of mouse actions.
>>
>
> You hit it right on the head. That's why it's not suitable as CAD, even
> though it's an extremely useful system for visual presentation.
>
> And although I might not have made it clear... that was my whole point on
> base-1.
>
> Lloyd
>


Lloyd, you simply do not know how to use Sketchup to its extents. Your
comments show your ignorance about Sketchup. I'm not trying to belittle
you but most every thing you have mentioned about Sketchup is inaccurate.

Again, I switched from AutoCAD to Sketchup about 6~8 years ago because I
get the same needed resolution and accuracy.

I am a woodworker and routinely work with pieces that measure in 1/8"
resolution however the program is quite capable of accurately and quite
quickly drawing a box that is 4 1/16 x 5 3/64 x 9 19/32.

don't knock the program until you actually learn how to use it, not just
play around with it.


I would be more than willing to show you some detailed drawing that I
have done with Sketchup.

On 11/25/2013 10:47 AM, Leon wrote:
> Now if you are talking about a higher degree of resolution, I would a
> agree that Sketchup begins to round after the fourth digit right of the
> point. .0001

Only for presentation, and depending upon the resolution you have set.

For dimensional computations, SketchUp still uses its internal accuracy,
the same as AutoCAD.

--
eWoodShop: www.eWoodShop.com
Wood Shop: www.e-WoodShop.net
google.com/+KarlCaillouet
http://www.custommade.com/by/ewoodshop/
KarlCaillouet@ (the obvious)

On 11/25/2013 9:24 AM, jim wrote:
>
>
> [email protected] wrote:
>>
>> On Sun, 24 Nov 2013 18:22:26 -0600, jim <"sjedgingN0Sp"@[email protected]>
>> wrote:
>>
>>>
>>>
>>> [email protected] wrote:
>>>>
>>>> On Sun, 24 Nov 2013 17:08:14 -0600, jim <"sjedgingN0Sp"@[email protected]>
>>>> wrote:
>>>>
>>>>>
>>>>>
>>>>> [email protected] wrote:
>>>>>
>>>>>>>
>>>>>>> People have been making things flat or round to that level of
>>>>>>> precision for ages.
>>>>>>
>>>>>> Flat and round (spherical) are trivial problems and as you note it's
>>>>>> been done for ages, at least since the middle ages.
>>>>>
>>>>> And there isn't much advantage in having a
>>>>> CAD model for those shapes.
>>>>
>>>> There isn't much reason to have a CAD model for a board, either, but
>>>> when you want to put a few dozen of them together, having a CAD model
>>>> gets rather interesting.
>>>>>
>>>>>
>>>>>> Other shapes are
>>>>>> more difficult, as is size.
>>>>>
>>>>> And it is doubtful there is anyone reading this who
>>>>> is cutting complex shapes from CAD models with precision
>>>>> held to tenths.
>>>>
>>>> Huh??? Have you ever heard of a mirror, or lens, system? Please
>>>> explain your statement?
>>>
>>> How many have you modeled in CAD and then manufactured
>>> to within tenth of the designed part?
>>
>> You still make no sense. Are you saying that precision machining
>> doesn't require the same level of modeling that sloppier work does?
>> Really?
>
> First of all most of the examples of precision that have
> been given involve no 3d modeling at all. And the rest
> appear to be at best 2d modeling (e.g.. a lathe profile).
>
>
> I'm saying that any CAD system can produce geometry that
> is far more accurate than any manufacturing process. If a 3d
> computer model has dimensions that are different than what you
> like them to be, it is because of the input the software was
> given, not because the software is sloppy.
>
> A program like Sketchup caters to people who want to
> model something that looks good without paying much attention
> precise numbers. But that doesn't mean it is sloppy. It just
> means it is not as easy to hit the exact numbers you may want as
> in other programs that cater to people who want models driven
> by precise numerical inputs instead of mouse actions.
>

I'm going to take exception to your wording in your last paragraph.
Maybe I misunderstood.

I was an AutoCAD user for about 8 years, other CAD programs since 1986.

Anyway I am a furniture designer and builder. I have completely
converted over to Sketchup.

Now where I might be confused with your wording is that if I draw
something that is 4" long it is precisely 4" If I draw 4.015625, I get
a line that is 4 1/64" long, precisely.

Now if you are talking about a higher degree of resolution, I would a
agree that Sketchup begins to round after the fourth digit right of the
point. .0001

In woodworking drawings it it is typically not necessary to measure in
increments that are smaller than 32ths of an inch.".

While that is true, Sketchup can still very accurately draw in
increments that are 1/64" or greater. Anything with in that resolution
works out just fine.

And for what it is worth, You can type in precise distances just like
with a CAD program with in the resolution that Sketchup operates.


After drawing a complex piece of furniture with Sketchup, sometimes with
hundreds of separate components I use a plug in program that takes the
exact over all dimensions of every component and imports that data,
accurately, into an optimization program that has my inventory of
materials. I cut the components overall sizes using the optimization
program with no reference to the Sketchup drawings of the actual project.

I will reference the drawings for specific details for each component
that may need to have tenons, dado's, slots, mortices, ect.

On 11/25/2013 1:00 PM, Swingman wrote:
> On 11/25/2013 12:52 PM, Leon wrote:
>
>> Understood, I was talking more about the actual drawn dimension having
>> limitations to their resolution.
>
> Like this:
>
> https://picasaweb.google.com/lh/photo/BlpE8eDGxPRV1nIUL5oqrdMTjNZETYmyPJy0liipFm0?feat=directlink
>
>
> ;)
>
>


No, can you think/tell me what that converts to as a fraction off the
top of your head? LOL My calculated industries calculator can't
either. ;~)

I like to see fractions, on my drawings, that I can actually come close
to reproducing. ;~)


A bit off topic, I checked the outside temp a few minutes ago,
42.51232367 degrees F.

"Leon" <lcb11211@swbelldotnet> wrote
>
> And for the most part a majority in this thread! LOL. There are a few
> that may not be and rightfully so but just because I drive a Maserati does
> not mean I use it to it's limits. The Camry works just fine and in many
> practical ways out performs the Maserati.

Far be it for me to criticize you Leon (you do good work) but I just can not
visualize you in a Camry. ;)

But your point is well taken.

Reminds me of a job I did years ago. I was working with corporate
publications and was hired to figure out the best way to send out
publications to a select group that needed updates on a semiregular basis.
I checked out several types of binding and distribution. My conclusion? 3
ring binders! I got them in contact with a source to make them up some
binders and dividers.. And it was a success. They just copied the
material on 3 hole sheets and sent it out. Simple. And better than any
other alternative. Simple trumps complicated crap every time. Particularly
if it gets the job done quick and easily.

On 11/25/2013 11:13 AM, Swingman wrote:
> On 11/25/2013 11:00 AM, Swingman wrote:
>> On 11/25/2013 10:47 AM, Leon wrote:
>>> Now if you are talking about a higher degree of resolution, I would a
>>> agree that Sketchup begins to round after the fourth digit right of the
>>> point. .0001
>>
>> Only for presentation, and depending upon the resolution you have set.
>>
>> For dimensional computations, SketchUp still uses its internal accuracy,
>> the same as AutoCAD.
>
> Here, do this:
>
> Open SU, go to Go to Window|Model Info|Units|Fractional and choose 1/64"
> or whatever Format you desire .
>
> Now, draw a rectangle of any size using the rectangle tool
>
> Select the rectangle and right click Area|Selection
>
> You will see a number representing the area of the rectangle you
> selected to .000000 precision.
>


Understood, I was talking more about the actual drawn dimension having
limitations to their resolution.

On 11/25/2013 11:49 AM, Lloyd E. Sponenburgh wrote:
> Leon <lcb11211@swbelldotnet> fired this volley in
> news:[email protected]:
>
>> I am a woodworker and routinely work with pieces that measure in 1/8"
>> resolution however the program is quite capable of accurately and quite
>> quickly drawing a box that is 4 1/16 x 5 3/64 x 9 19/32.
>
> If I were using it for woodworking, I assume those accuracies would be
> adequate, if a little gross for a CNC router...

Not in the slightest for a CNC. Why would one choose odd ball
tolerances, tiny fractions, when working with wood? Sketch up is being
used for CNC machines and 3D printers.

Metal working in some cases would be another matter.



>
> But I work daily with sub-thousandth measurements. Do you really
> understand how funny dealing with "thirty-secondths" sounds to a
> metalworker? Today, I had to lay out a complex, multi-curved cam slot a
> half-thousanth wider than a bearing, because the bearings that ride in it
> work the plus side of their tolerances -- and the bearings are spec'd by
> the customer. Even two thousanths of an inch would cause them to track
> wrong.


And given the OP's original post to this thread do you realize how funny
it sounds to use a program that uses the resolutions that you are
speaking about when Sketchup is more than capable of satisfying his
needs for free?

I realize you work with high resolutions, that is the requirement of
metal working. But Sketchup is far more of a program than to simply
sketch out pencil type drawings.


>
> I also am not belittling what you do. I've done it (in a prior life)
> with very nice results on some 'fine' reproduction furniture. They're
> just not the same games, that's all.

And Sketchup would be more than fine for reproduction furniture drawings.


>
> I have -eh- maybe 250-300 hours building large-scale models in Sketchup;
> 100 meter scale. Maybe I could finesse it into doing 1/4" stuff to
> tenths of a thou.; but why, when there are CAMs out there well-adapted to
> what machinists do? Why use an axe where a scalpel is called for?


So with that kind of time put in with Sketchup you are just getting
started. I have many more drawings than you have in hours and most of
the drawings require 10~20 hours of design.

If you need that higher resolution use the program that works but your
descriptions of the capabilities of Sketchup makes one wonder if you
really know what it can do.

I think the biggest problem with this whole thread is that the OP posted
to wood working and metal working. His first item on his wish list was
for wood boards and followed by stuff you make at home. He had the
knowledge of 2D CAD programs so he was not totally ignorant of what to
use but IMHO he wanted to do 3D for, most likely, less than extreme
resolution drawings.

On 11/25/2013 1:20 PM, Swingman wrote:
> On 11/25/2013 1:17 PM, Leon wrote:
>> On 11/25/2013 12:56 PM, Swingman wrote:
>>> On 11/25/2013 12:34 PM, Leon wrote:
>>>> I think the biggest problem with this whole thread is that the OP
>>>> posted
>>>> to wood working and metal working. His first item on his wish list was
>>>> for wood boards and followed by stuff you make at home. He had the
>>>> knowledge of 2D CAD programs so he was not totally ignorant of what to
>>>> use but IMHO he wanted to do 3D for, most likely, less than extreme
>>>> resolution drawings.
>>>
>>>
>>> My bet is that the OP would be much more than perfectly happy with this
>>> for his simple "3-D metal" drawings:
>>>
>>> https://lh3.googleusercontent.com/-nUVUXF4Ods0/UpOS_ypsf_I/AAAAAAAAUys/V6amC_suz40/s1440/Untitled.jpg
>>>
>>>
>>>
>>>
>>> :)
>>
>> And for the most part a majority in this thread! LOL. There are a few
>> that may not be and rightfully so but just because I drive a Maserati
>> does not mean I use it to it's limits. The Camry works just fine and in
>> many practical ways out performs the Maserati.
>
>
> LOL ... just ragging on you a bit, Bubba. ;)
>

I know! LOL Idle hands. Too friggen cold in the shop.

On 11/25/2013 1:00 PM, Swingman wrote:
> On 11/25/2013 12:52 PM, Leon wrote:
>
>> Understood, I was talking more about the actual drawn dimension having
>> limitations to their resolution.
>
> Like this:
>
> https://picasaweb.google.com/lh/photo/BlpE8eDGxPRV1nIUL5oqrdMTjNZETYmyPJy0liipFm0?feat=directlink
>
>
> ;)
>
>


No, can you think/tell me what that converts to as a fraction off the
top of your head? LOL My calculated industries calculator can't
either. ;~)

I like to see fractions, on my drawings, that I can actually come close
to reproducing. ;~)


A bit off topic, I checked the outside temp a few minutes ago,
42.51232367 degrees F.

On 11/25/2013 1:27 PM, Leon wrote:
> On 11/25/2013 1:00 PM, Swingman wrote:
>> On 11/25/2013 12:52 PM, Leon wrote:
>>
>>> Understood, I was talking more about the actual drawn dimension having
>>> limitations to their resolution.
>>
>> Like this:
>>
>> https://picasaweb.google.com/lh/photo/BlpE8eDGxPRV1nIUL5oqrdMTjNZETYmyPJy0liipFm0?feat=directlink
>>
>>
>>
>> ;)
>>
>>
>
>
> No, can you think/tell me what that converts to as a fraction off the
> top of your head? LOL My calculated industries calculator can't
> either. ;~)
>
> I like to see fractions, on my drawings, that I can actually come close
> to reproducing. ;~)
>
>
> A bit off topic, I checked the outside temp a few minutes ago,
> 42.51232367 degrees F.

ROTFLMAO


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On 11/25/2013 10:18 AM, jim wrote:
>
>
> Richard wrote:
>>
>> On 11/25/2013 9:24 AM, jim wrote:
>>
>>> First of all most of the examples of precision that have
>>> been given involve no 3d modeling at all. And the rest
>>> appear to be at best 2d modeling (e.g.. a lathe profile).
>>
>> Huh?
>> I guess you didn't check out my offerings?
>>
>> http://www.home.earthlink.net/~cavelamb/draft.htm
>>
>> Lofted to .01 inch, since traditional nail in the floor
>> lofting considered 1/8th inch superb fairing.
>
> I did look. And its nice work.
> But you aren't claiming that you took
> a 3d model and produced a part held to tenth
> accuracy. If you can achieve .01" accuracy in
> manufacturing that hull to match the 3d model,
> that would be extraordinary
> accuracy.


I'm sorry, Jim, but this sounds like arguing just for the sake of arguing.

Drafting (or modeling) and machining are two distinctly different
disciplines and outside of a few hobbyist, damned few people do both.

A fiberglass boat's hull is seldom held to anywhere near that accuracy.
If you check carefully you will usually find all manner of inaccuracy in
construction. Missed dimensions (by INCHES some times), asymmetry,
misalignment, etc, that the eye simply does not catch.

On the other hand, large steel ships MUST hold that kind of accuracy.
Those ships are built in smaller sections called "lifts", which are
then stacked together to form the finished structure. They HAVE to be
built that accurately just to fit together.

For what it's worth...

Jim Wilkins wrote:
>
> "jim" <"sjedgingN0Sp"@[email protected]> wrote in his blissful ignorance
> >> On Sun, 24 Nov 2013 18:22:26 -0600, jim <"sjedgingN0Sp"@[email protected]>
> >> wrote:
> >> >[email protected] wrote:
> >> >>
> >> >> On Sun, 24 Nov 2013 17:08:14 -0600, jim
> >> >> <"sjedgingN0Sp"@[email protected]>
> >> >> wrote:
> >> >
> >> >How many have you modeled in CAD and then manufactured
> >> >to within tenth of the designed part?
> >>
> >> You still make no sense. Are you saying that precision machining
> >> doesn't require the same level of modeling that sloppier work does?
> >> Really?
> >
> > First of all most of the examples of precision that have
> > been given involve no 3d modeling at all. And the rest
> > appear to be at best 2d modeling (e.g.. a lathe profile).
> >
> >
> > I'm saying that any CAD system can produce geometry that
> > is far more accurate than any manufacturing process. If a 3d
> > computer model has dimensions that are different than what you
> > like them to be, it is because of the input the software was
> > given, not because the software is sloppy.
>
> http://www.mmsonline.com/articles/getting-to-submicron-accuracy
> "The axis position feedback system uses a 0.5-nanometer scale to
> reliably track axis motion commands programmable in steps as small as
> 10 nanometers."

Yes that machine should be able to cut 3d parts so they match
the 3d computer geometry to within a tenth.
However, the CAD model of the part can be made a million times more
accurate than even that machine can manufacture.

I didn't say there were no way to produce complicated 3d
parts that are within a tenth of the 3d CAD model.
I said that I doubt anyone reading this was doing that. You
still haven't changed my mind.



>
> I've watched a large aspherical Germanium infrared camera lens being
> diamond-turned to a mirror-like submicron finish on a CNC lathe.

Turning something on a lathe doesn't need a 3d model.
That is not 3d machining.

And watching someone else do it doesn't count as doing.

On 11/25/2013 9:34 AM, Lloyd E. Sponenburgh wrote:
> jim <"sjedgingN0Sp"@[email protected]> fired this volley in
> news:[email protected]:
>
>> But that doesn't mean it is sloppy. It just
>> means it is not as easy to hit the exact numbers you may want as
>> in other programs that cater to people who want models driven
>> by precise numerical inputs instead of mouse actions.
>>
>
> You hit it right on the head. That's why it's not suitable as CAD, even
> though it's an extremely useful system for visual presentation.
>
> And although I might not have made it clear... that was my whole point on
> base-1.

Except that what you quoted as justification for your "whole point" is
incorrect, therefore you're still wrong.

With SketchUp, "precise numerical inputs" can be input to the same
precision as AutoCAD, by simply using the keyboard.

Try again ...

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On 11/25/2013 11:23 AM, jim wrote:
>
>
>>
Snip


>>>
>>> A program like Sketchup caters to people who want to
>>> model something that looks good without paying much attention
>>> precise numbers. But that doesn't mean it is sloppy. It just
>>> means it is not as easy to hit the exact numbers you may want as
>>> in other programs that cater to people who want models driven
>>> by precise numerical inputs instead of mouse actions.
>>>
>>
>> I'm going to take exception to your wording in your last paragraph.
>> Maybe I misunderstood.
>>
>> I was an AutoCAD user for about 8 years, other CAD programs since 1986.
>>
>> Anyway I am a furniture designer and builder. I have completely
>> converted over to Sketchup.
>>
>> Now where I might be confused with your wording is that if I draw
>> something that is 4" long it is precisely 4" If I draw 4.015625, I get
>> a line that is 4 1/64" long, precisely.
>>
>
> Yes. I said you can do it if you want to, but the program
> is obviously targeted at people who want to use the mouse
> for input.

What gives you that thought. I mostly use the mouse simply to start a
line and to give that line a direction to move relative to the starting
point. It is keyboard input from there. For that matter you can mostly
use a mouse with AutoCAD.

And, if one prefers to use a mouse or a mouse and a 3D input device what
difference does it make which program you use as long as the program is
capable of getting the job done.

Am I detecting a bit of snobbery here? ;~)

I thought the same about Sketchup when I was using AutoCAD, In fact I
had installed and uninstalled 3 different versions of Sketchup before it
dawned on me that Sketchup was way better for woodworking than AutoCAD.


>
>> Now if you are talking about a higher degree of resolution, I would a
>> agree that Sketchup begins to round after the fourth digit right of the
>> point. .0001
>>
>
> It looks like it can take much more precise input than that.
> There is a setting in the units dialog box. And you
> don't have to work in fractions. You can switch to decimals
> and input numbers down to a millionth of a mm. Internally,
> the data is even more precise than that.

That is correct. I tend to input/draw in decimals, much faster than
inputting fractions, but work in fractions in the shop so the drawings
are also in fractions.

On 11/25/2013 1:33 PM, jim wrote:
>
>
> Leon wrote:
>>
>> On 11/25/2013 11:23 AM, jim wrote:
>>>
>>>
>>>>
>> Snip
>>
>>>>>
>>>>> A program like Sketchup caters to people who want to
>>>>> model something that looks good without paying much attention
>>>>> precise numbers. But that doesn't mean it is sloppy. It just
>>>>> means it is not as easy to hit the exact numbers you may want as
>>>>> in other programs that cater to people who want models driven
>>>>> by precise numerical inputs instead of mouse actions.
>>>>>
>>>>
>>>> I'm going to take exception to your wording in your last paragraph.
>>>> Maybe I misunderstood.
>>>>
>>>> I was an AutoCAD user for about 8 years, other CAD programs since 1986.
>>>>
>>>> Anyway I am a furniture designer and builder. I have completely
>>>> converted over to Sketchup.
>>>>
>>>> Now where I might be confused with your wording is that if I draw
>>>> something that is 4" long it is precisely 4" If I draw 4.015625, I get
>>>> a line that is 4 1/64" long, precisely.
>>>>
>>>
>>> Yes. I said you can do it if you want to, but the program
>>> is obviously targeted at people who want to use the mouse
>>> for input.
>>
>> What gives you that thought.
>
> I looked at their promotional videos. I didn't see anything
> showing off its abilities to make numerically driven
> models. It looks like it may be okay for cabinet work, but
> what about something like making the scroll on a violin?
>
> http://www.gussetviolins.com/untitled-1.jpg
> http://t1.gstatic.com/images?q=tbn:ANd9GcQKPv8gAgVzHKvZYp10WE4HY1GyHkmZsqZOTP-UKN7lYyduBV9mZg
>

Should not be a problem. Actually I just down loaded one from the 3D
warehouse, rather the whole violin.

http://www.flickr.com/photos/lcb11211/11054578036/

On 11/25/2013 4:24 PM, Leon wrote:
> On 11/25/2013 4:09 PM, Lee Michaels wrote:
>>
>>
>> "Leon" <lcb11211@swbelldotnet> wrote
>>>
>>> And for the most part a majority in this thread! LOL. There are a
>>> few that may not be and rightfully so but just because I drive a
>>> Maserati does not mean I use it to it's limits. The Camry works just
>>> fine and in many practical ways out performs the Maserati.
>>
>> Far be it for me to criticize you Leon (you do good work) but I just can
>> not visualize you in a Camry. ;)
>
> LOL, Then picture me on a Maserati. ;~) Actually a 2012 Camry SE V6 and
> 07 Tundra.
>
>

Leon, you need to come check in at ToyotaNation(dot)com forums.
All the cool kids hang out there.

On 11/25/2013 11:00 AM, Swingman wrote:
> On 11/25/2013 10:47 AM, Leon wrote:
>> Now if you are talking about a higher degree of resolution, I would a
>> agree that Sketchup begins to round after the fourth digit right of the
>> point. .0001
>
> Only for presentation, and depending upon the resolution you have set.
>
> For dimensional computations, SketchUp still uses its internal accuracy,
> the same as AutoCAD.
>



Speaking of which, I have a plug in for chaining the units, precision of
the units, type of units, etc with out having to open up the Sketchup
Dialog box.

On 11/25/2013 4:09 PM, Lee Michaels wrote:
>
>
> "Leon" <lcb11211@swbelldotnet> wrote
>>
>> And for the most part a majority in this thread! LOL. There are a
>> few that may not be and rightfully so but just because I drive a
>> Maserati does not mean I use it to it's limits. The Camry works just
>> fine and in many practical ways out performs the Maserati.
>
> Far be it for me to criticize you Leon (you do good work) but I just can
> not visualize you in a Camry. ;)

LOL, Then picture me on a Maserati. ;~) Actually a 2012 Camry SE V6
and 07 Tundra.







> But your point is well taken.
>
> Reminds me of a job I did years ago. I was working with corporate
> publications and was hired to figure out the best way to send out
> publications to a select group that needed updates on a semiregular
> basis. I checked out several types of binding and distribution. My
> conclusion? 3 ring binders! I got them in contact with a source to
> make them up some binders and dividers.. And it was a success. They
> just copied the material on 3 hole sheets and sent it out. Simple.
> And better than any other alternative. Simple trumps complicated crap
> every time. Particularly if it gets the job done quick and easily.
>
>
>
>
>
>

On 11/25/2013 12:52 PM, Leon wrote:

> Understood, I was talking more about the actual drawn dimension having
> limitations to their resolution.

Like this:

https://picasaweb.google.com/lh/photo/BlpE8eDGxPRV1nIUL5oqrdMTjNZETYmyPJy0liipFm0?feat=directlink

;)


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On 11/25/2013 12:34 PM, Leon wrote:
> I think the biggest problem with this whole thread is that the OP posted
> to wood working and metal working. His first item on his wish list was
> for wood boards and followed by stuff you make at home. He had the
> knowledge of 2D CAD programs so he was not totally ignorant of what to
> use but IMHO he wanted to do 3D for, most likely, less than extreme
> resolution drawings.


My bet is that the OP would be much more than perfectly happy with this
for his simple "3-D metal" drawings:

https://lh3.googleusercontent.com/-nUVUXF4Ods0/UpOS_ypsf_I/AAAAAAAAUys/V6amC_suz40/s1440/Untitled.jpg


:)


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jim <"sjedgingN0Sp"@[email protected]> fired this volley in
news:[email protected]:

> But that doesn't mean it is sloppy. It just
> means it is not as easy to hit the exact numbers you may want as
> in other programs that cater to people who want models driven
> by precise numerical inputs instead of mouse actions.
>

You hit it right on the head. That's why it's not suitable as CAD, even
though it's an extremely useful system for visual presentation.

And although I might not have made it clear... that was my whole point on
base-1.

Lloyd

Leon <lcb11211@swbelldotnet> fired this volley in
news:[email protected]:

> I am a woodworker and routinely work with pieces that measure in 1/8"
> resolution however the program is quite capable of accurately and quite
> quickly drawing a box that is 4 1/16 x 5 3/64 x 9 19/32.

If I were using it for woodworking, I assume those accuracies would be
adequate, if a little gross for a CNC router...

But I work daily with sub-thousandth measurements. Do you really
understand how funny dealing with "thirty-secondths" sounds to a
metalworker? Today, I had to lay out a complex, multi-curved cam slot a
half-thousanth wider than a bearing, because the bearings that ride in it
work the plus side of their tolerances -- and the bearings are spec'd by
the customer. Even two thousanths of an inch would cause them to track
wrong.

I also am not belittling what you do. I've done it (in a prior life)
with very nice results on some 'fine' reproduction furniture. They're
just not the same games, that's all.

I have -eh- maybe 250-300 hours building large-scale models in Sketchup;
100 meter scale. Maybe I could finesse it into doing 1/4" stuff to
tenths of a thou.; but why, when there are CAMs out there well-adapted to
what machinists do? Why use an axe where a scalpel is called for?

Lloyd

On 11/25/2013 9:24 AM, jim wrote:


> First of all most of the examples of precision that have
> been given involve no 3d modeling at all. And the rest
> appear to be at best 2d modeling (e.g.. a lathe profile).




Huh?
I guess you didn't check out my offerings?

http://www.home.earthlink.net/~cavelamb/draft.htm

Lofted to .01 inch, since traditional nail in the floor
lofting considered 1/8th inch superb fairing.

On 11/26/2013 10:11 AM, Edward A. Falk wrote:

> I've had a lot of trouble with Sketchup working in sub-1/4"
> sizes. I'm making some toys for a friend now with parts down
> to 1mm.

> Try it yourself at home: make a 1/4" sphere by sweeping a circle
> over 180 degrees, or any other way you want.
>
> What I normally do is scale my model up 1000x, work on it, and
> then scale it back down.
>
> It shouldn't be like that, and I'm not entirely sure why it is;
> precise or not, it shouldn't be so affected by working scale factor.
>
> I see this a lot in models downloaded from the warehouse. You download
> a chess set or something, and find out all the pieces are ten feet tall.

Every single item above due solely to total lack of understanding of how
the software works, just as those who use a screw driver for a hammer
won't be happy with the results.

Instead of rebutting the operator error in each statement above, start
here to learn how to correctly use the software:

http://www.sketchup.com/learn/videos?playlist=58

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On 11/26/2013 6:49 PM, Edward A. Falk wrote:

> Try this exercise: make a hemisphere 1/4" in diameter.
>
> Seehttp://imgur.com/a/E3J4p for two hemispheres I made in Sketchup.
> One was 0.125" in radius and the other was 125" in radius. I used the
> exact same technique to make each of them. I was using Sketchup 8.
>
> I've tried it using different techniques in the past, and had
> different results, but they were still wrong.
>
> If you can create this shape at 1/4" scale, I'd be interested in
> finding out how you did it. I suppose if you're more persistent than
> I was, you'll find a way. But as far as I know, the only way is to
> make it larger, then shrink it down.

What techniques did you use and what was the error/problem?

I'm assuming you used the "follow me" tool and two concentric circles to
draw your sphere?

Don't have time this morning to check it out, but the first question
that comes to mind is did you "divide" your arc(s) into smaller segments
to get a smoother curve, and if so, how many?

I see how this could be a processor/graphics subsystem limit because
using smaller line segments (100) on an arc eats up a lot of cpu cycles.

Interesting, I'll give it shot this evening, but it would help to know
what error you experienced.

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[email protected] wrote:
>
> On Sun, 24 Nov 2013 18:22:26 -0600, jim <"sjedgingN0Sp"@[email protected]>
> wrote:
>
> >
> >
> >[email protected] wrote:
> >>
> >> On Sun, 24 Nov 2013 17:08:14 -0600, jim <"sjedgingN0Sp"@[email protected]>
> >> wrote:
> >>
> >> >
> >> >
> >> >[email protected] wrote:
> >> >
> >> >> >
> >> >> >People have been making things flat or round to that level of
> >> >> >precision for ages.
> >> >>
> >> >> Flat and round (spherical) are trivial problems and as you note it's
> >> >> been done for ages, at least since the middle ages.
> >> >
> >> >And there isn't much advantage in having a
> >> >CAD model for those shapes.
> >>
> >> There isn't much reason to have a CAD model for a board, either, but
> >> when you want to put a few dozen of them together, having a CAD model
> >> gets rather interesting.
> >> >
> >> >
> >> >> Other shapes are
> >> >> more difficult, as is size.
> >> >
> >> >And it is doubtful there is anyone reading this who
> >> >is cutting complex shapes from CAD models with precision
> >> >held to tenths.
> >>
> >> Huh??? Have you ever heard of a mirror, or lens, system? Please
> >> explain your statement?
> >
> >How many have you modeled in CAD and then manufactured
> >to within tenth of the designed part?
>
> You still make no sense. Are you saying that precision machining
> doesn't require the same level of modeling that sloppier work does?
> Really?

First of all most of the examples of precision that have
been given involve no 3d modeling at all. And the rest
appear to be at best 2d modeling (e.g.. a lathe profile).


I'm saying that any CAD system can produce geometry that
is far more accurate than any manufacturing process. If a 3d
computer model has dimensions that are different than what you
like them to be, it is because of the input the software was
given, not because the software is sloppy.

A program like Sketchup caters to people who want to
model something that looks good without paying much attention
precise numbers. But that doesn't mean it is sloppy. It just
means it is not as easy to hit the exact numbers you may want as
in other programs that cater to people who want models driven
by precise numerical inputs instead of mouse actions.

Leon wrote:
>
> On 11/25/2013 9:24 AM, jim wrote:
> >
> >
> > [email protected] wrote:
> >>
> >> On Sun, 24 Nov 2013 18:22:26 -0600, jim <"sjedgingN0Sp"@[email protected]>
> >> wrote:
> >>
> >>>
> >>>
> >>> [email protected] wrote:
> >>>>
> >>>> On Sun, 24 Nov 2013 17:08:14 -0600, jim <"sjedgingN0Sp"@[email protected]>
> >>>> wrote:
> >>>>
> >>>>>
> >>>>>
> >>>>> [email protected] wrote:
> >>>>>
> >>>>>>>
> >>>>>>> People have been making things flat or round to that level of
> >>>>>>> precision for ages.
> >>>>>>
> >>>>>> Flat and round (spherical) are trivial problems and as you note it's
> >>>>>> been done for ages, at least since the middle ages.
> >>>>>
> >>>>> And there isn't much advantage in having a
> >>>>> CAD model for those shapes.
> >>>>
> >>>> There isn't much reason to have a CAD model for a board, either, but
> >>>> when you want to put a few dozen of them together, having a CAD model
> >>>> gets rather interesting.
> >>>>>
> >>>>>
> >>>>>> Other shapes are
> >>>>>> more difficult, as is size.
> >>>>>
> >>>>> And it is doubtful there is anyone reading this who
> >>>>> is cutting complex shapes from CAD models with precision
> >>>>> held to tenths.
> >>>>
> >>>> Huh??? Have you ever heard of a mirror, or lens, system? Please
> >>>> explain your statement?
> >>>
> >>> How many have you modeled in CAD and then manufactured
> >>> to within tenth of the designed part?
> >>
> >> You still make no sense. Are you saying that precision machining
> >> doesn't require the same level of modeling that sloppier work does?
> >> Really?
> >
> > First of all most of the examples of precision that have
> > been given involve no 3d modeling at all. And the rest
> > appear to be at best 2d modeling (e.g.. a lathe profile).
> >
> >
> > I'm saying that any CAD system can produce geometry that
> > is far more accurate than any manufacturing process. If a 3d
> > computer model has dimensions that are different than what you
> > like them to be, it is because of the input the software was
> > given, not because the software is sloppy.
> >
> > A program like Sketchup caters to people who want to
> > model something that looks good without paying much attention
> > precise numbers. But that doesn't mean it is sloppy. It just
> > means it is not as easy to hit the exact numbers you may want as
> > in other programs that cater to people who want models driven
> > by precise numerical inputs instead of mouse actions.
> >
>
> I'm going to take exception to your wording in your last paragraph.
> Maybe I misunderstood.
>
> I was an AutoCAD user for about 8 years, other CAD programs since 1986.
>
> Anyway I am a furniture designer and builder. I have completely
> converted over to Sketchup.
>
> Now where I might be confused with your wording is that if I draw
> something that is 4" long it is precisely 4" If I draw 4.015625, I get
> a line that is 4 1/64" long, precisely.
>

Yes. I said you can do it if you want to, but the program
is obviously targeted at people who want to use the mouse
for input.



> Now if you are talking about a higher degree of resolution, I would a
> agree that Sketchup begins to round after the fourth digit right of the
> point. .0001
>

It looks like it can take much more precise input than that.
There is a setting in the units dialog box. And you
don't have to work in fractions. You can switch to decimals
and input numbers down to a millionth of a mm. Internally,
the data is even more precise than that.

On 11/25/2013 11:00 AM, Leon wrote:
> don't knock the program until you actually learn how to use it, not just
> play around with it.

Ayup ...One would hope that their accuracy in their work indeed exceeds
their accuracy/misconceptions about a program with which they obviously
have little familiarity. ;)

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On 11/25/2013 12:56 PM, Swingman wrote:
> On 11/25/2013 12:34 PM, Leon wrote:
>> I think the biggest problem with this whole thread is that the OP posted
>> to wood working and metal working. His first item on his wish list was
>> for wood boards and followed by stuff you make at home. He had the
>> knowledge of 2D CAD programs so he was not totally ignorant of what to
>> use but IMHO he wanted to do 3D for, most likely, less than extreme
>> resolution drawings.
>
>
> My bet is that the OP would be much more than perfectly happy with this
> for his simple "3-D metal" drawings:
>
> https://lh3.googleusercontent.com/-nUVUXF4Ods0/UpOS_ypsf_I/AAAAAAAAUys/V6amC_suz40/s1440/Untitled.jpg
>
>
> :)
>
>


And for the most part a majority in this thread! LOL. There are a few
that may not be and rightfully so but just because I drive a Maserati
does not mean I use it to it's limits. The Camry works just fine and in
many practical ways out performs the Maserati.

"jim" <"sjedgingN0Sp"@[email protected]> wrote in his blissful ignorance
>> On Sun, 24 Nov 2013 18:22:26 -0600, jim <"sjedgingN0Sp"@[email protected]>
>> wrote:
>> >[email protected] wrote:
>> >>
>> >> On Sun, 24 Nov 2013 17:08:14 -0600, jim
>> >> <"sjedgingN0Sp"@[email protected]>
>> >> wrote:
>> >
>> >How many have you modeled in CAD and then manufactured
>> >to within tenth of the designed part?
>>
>> You still make no sense. Are you saying that precision machining
>> doesn't require the same level of modeling that sloppier work does?
>> Really?
>
> First of all most of the examples of precision that have
> been given involve no 3d modeling at all. And the rest
> appear to be at best 2d modeling (e.g.. a lathe profile).
>
>
> I'm saying that any CAD system can produce geometry that
> is far more accurate than any manufacturing process. If a 3d
> computer model has dimensions that are different than what you
> like them to be, it is because of the input the software was
> given, not because the software is sloppy.


http://www.mmsonline.com/articles/getting-to-submicron-accuracy
"The axis position feedback system uses a 0.5-nanometer scale to
reliably track axis motion commands programmable in steps as small as
10 nanometers."

I've watched a large aspherical Germanium infrared camera lens being
diamond-turned to a mirror-like submicron finish on a CNC lathe.
http://media.defenceindustrydaily.com/images/ORD_RWS_Kongsberg_M151_Protector_on_M1126_Stryker_Mosul_lg.jpg

All you demonstrate is that YOU don't know how to do this.

jsw

"jim" <"sjedgingN0Sp"@[email protected]> wrote in message
news:[email protected]...
>
>
> Jim Wilkins wrote:
>>
>> "jim" <"sjedgingN0Sp"@[email protected]> wrote in his blissful ignorance
>> >> On Sun, 24 Nov 2013 18:22:26 -0600, jim
>> >> <"sjedgingN0Sp"@[email protected]>
>> >> wrote:
>> >> >[email protected] wrote:
>> >> >>
>> >> >> On Sun, 24 Nov 2013 17:08:14 -0600, jim
>> >> >> <"sjedgingN0Sp"@[email protected]>
>> >> >> wrote:
>> >> >
>> >> >How many have you modeled in CAD and then manufactured
>> >> >to within tenth of the designed part?
>> >>
>> >> You still make no sense. Are you saying that precision
>> >> machining
>> >> doesn't require the same level of modeling that sloppier work
>> >> does?
>> >> Really?
>> >
>> > First of all most of the examples of precision that have
>> > been given involve no 3d modeling at all. And the rest
>> > appear to be at best 2d modeling (e.g.. a lathe profile).
>> >
>> >
>> > I'm saying that any CAD system can produce geometry that
>> > is far more accurate than any manufacturing process. If a 3d
>> > computer model has dimensions that are different than what you
>> > like them to be, it is because of the input the software was
>> > given, not because the software is sloppy.
>>
>> http://www.mmsonline.com/articles/getting-to-submicron-accuracy
>> "The axis position feedback system uses a 0.5-nanometer scale to
>> reliably track axis motion commands programmable in steps as small
>> as
>> 10 nanometers."
>
> Yes that machine should be able to cut 3d parts so they match
> the 3d computer geometry to within a tenth.
> However, the CAD model of the part can be made a million times more
> accurate than even that machine can manufacture.
>
> I didn't say there were no way to produce complicated 3d
> parts that are within a tenth of the 3d CAD model.
> I said that I doubt anyone reading this was doing that. You
> still haven't changed my mind.
>
>
>
>>
>> I've watched a large aspherical Germanium infrared camera lens
>> being
>> diamond-turned to a mirror-like submicron finish on a CNC lathe.
>
> Turning something on a lathe doesn't need a 3d model.
> That is not 3d machining.
>
> And watching someone else do it doesn't count as doing.

You are demonstrating my point that petulant misfits will snatch at
any excuse to belittle capable people.

Swingman wrote:
> On 11/25/2013 1:27 PM, Leon wrote:
>> On 11/25/2013 1:00 PM, Swingman wrote:
>>> On 11/25/2013 12:52 PM, Leon wrote:
>>>
>>>> Understood, I was talking more about the actual drawn dimension
>>>> having limitations to their resolution.
>>>
>>> Like this:
>>>
>>> https://picasaweb.google.com/lh/photo/BlpE8eDGxPRV1nIUL5oqrdMTjNZETYmyPJy0liipFm0?feat=directlink
>>>
>>>
>>>
>>> ;)
>>>
>>>
>>
>>
>> No, can you think/tell me what that converts to as a fraction off the
>> top of your head? LOL My calculated industries calculator can't
>> either. ;~)
>>
>> I like to see fractions, on my drawings, that I can actually come
>> close to reproducing. ;~)
>>
>>
>> A bit off topic, I checked the outside temp a few minutes ago,
>> 42.51232367 degrees F.
>
> ROTFLMAO

Would you two quit arguing? This is getting embarassing...

--

-Mike-
[email protected]

"DoN. Nichols" <[email protected]> wrote in message
news:[email protected]...

Very good description!

I've memorized the decimals down to 16ths but the simple approach is
to hang a decimal equivalents chart near the machine, as it also gives
the nearest fractional or metric collet size to your workpiece
diameter and shows english-metric equivalents.
http://cdn.mscdirect.com/global/images/ProductImages/0651680A-11.jpg
jsw

In article <[email protected]>,
jim <"sjedgingN0Sp"@[email protected]> wrote:
>
>
>I'm saying that any CAD system can produce geometry that
>is far more accurate than any manufacturing process.

Fun fact: when they built the difference engines from Babbage's
designs, they needed to compensate for the fact that the CNC
machine they were building it on was accurate to 1/10,000
inch but the manufacturing processes of Babbage's time were
only accurate to 1/2000 inch.

They not only wanted to know if the machine would work as Babbage designed
it, but they wanted to know if Babbage could really have built it.
So they added 1/2000" of random noise to the CNC data before giving the
data to the machines.


> A program like Sketchup caters to people who want to
>model something that looks good without paying much attention
>precise numbers. But that doesn't mean it is sloppy. It just
>means it is not as easy to hit the exact numbers you may want as
>in other programs that cater to people who want models driven
>by precise numerical inputs instead of mouse actions.

I've had a lot of trouble with Sketchup working in sub-1/4"
sizes. I'm making some toys for a friend now with parts down
to 1mm.

Try it yourself at home: make a 1/4" sphere by sweeping a circle
over 180 degrees, or any other way you want.

What I normally do is scale my model up 1000x, work on it, and
then scale it back down.

It shouldn't be like that, and I'm not entirely sure why it is;
precise or not, it shouldn't be so affected by working scale factor.

I see this a lot in models downloaded from the warehouse. You download
a chess set or something, and find out all the pieces are ten feet tall.

--
-Ed Falk, [email protected]
http://thespamdiaries.blogspot.com/

On 11/26/2013 11:11 AM, Edward A. Falk wrote:
> In article <[email protected]>,
> jim <"sjedgingN0Sp"@[email protected]> wrote:
>>
>>
>> I'm saying that any CAD system can produce geometry that
>> is far more accurate than any manufacturing process.
>
> Fun fact: when they built the difference engines from Babbage's
> designs, they needed to compensate for the fact that the CNC
> machine they were building it on was accurate to 1/10,000
> inch but the manufacturing processes of Babbage's time were
> only accurate to 1/2000 inch.
>
> They not only wanted to know if the machine would work as Babbage designed
> it, but they wanted to know if Babbage could really have built it.
> So they added 1/2000" of random noise to the CNC data before giving the
> data to the machines.
>
>
>> A program like Sketchup caters to people who want to
>> model something that looks good without paying much attention
>> precise numbers. But that doesn't mean it is sloppy. It just
>> means it is not as easy to hit the exact numbers you may want as
>> in other programs that cater to people who want models driven
>> by precise numerical inputs instead of mouse actions.
>
> I've had a lot of trouble with Sketchup working in sub-1/4"
> sizes. I'm making some toys for a friend now with parts down
> to 1mm.
>
> Try it yourself at home: make a 1/4" sphere by sweeping a circle
> over 180 degrees, or any other way you want.
>
> What I normally do is scale my model up 1000x, work on it, and
> then scale it back down.
>
> It shouldn't be like that, and I'm not entirely sure why it is;
> precise or not, it shouldn't be so affected by working scale factor.
>
> I see this a lot in models downloaded from the warehouse. You download
> a chess set or something, and find out all the pieces are ten feet tall.
>

If you design something large, and shrink it, it will probably look
better. Compare to the pixel resolution of digital images.

"Edward A. Falk" <[email protected]> wrote in message
news:[email protected]...
> In article <[email protected]>,
>
> Fun fact: when they built the difference engines from Babbage's
> designs, they needed to compensate for the fact that the CNC
> machine they were building it on was accurate to 1/10,000
> inch but the manufacturing processes of Babbage's time were
> only accurate to 1/2000 inch.
>
> They not only wanted to know if the machine would work as Babbage
> designed
> it, but they wanted to know if Babbage could really have built it.
> So they added 1/2000" of random noise to the CNC data before giving
> the
> data to the machines.
>

The machine was built by Joseph Clement, one of the founding geniuses
of the Industrial Revolution, who learned his skills from the great
masters Joseph Bramah and Henry Maudslay.
http://en.wikipedia.org/wiki/Joseph_Clement
"The recognised excellence of Clement's machine tools and his skill in
precision engineering led to him being employed by Charles Babbage in
1823 to work on his project to design and build his mechanical
calculating device, the difference engine."

jsw

In article <[email protected]>,
Jim Wilkins <[email protected]> wrote:
>"Edward A. Falk" <[email protected]> wrote in message
>news:[email protected]...
>> In article <[email protected]>,
>>
>> They not only wanted to know if the machine would work as Babbage
>> designed
>> it, but they wanted to know if Babbage could really have built it.
>> So they added 1/2000" of random noise to the CNC data before giving
>> the
>> data to the machines.
>>
>
>The machine was built by Joseph Clement, one of the founding geniuses
>of the Industrial Revolution, who learned his skills from the great
>masters Joseph Bramah and Henry Maudslay.
>http://en.wikipedia.org/wiki/Joseph_Clement
>"The recognised excellence of Clement's machine tools and his skill in
>precision engineering led to him being employed by Charles Babbage in
>1823 to work on his project to design and build his mechanical
>calculating device, the difference engine."

They say that Babbage helped launch the industrial revolution.
The difference engine required a whole new level of precision, and many
engineers were trained up working on the project. When the project
finally failed, a whole bunch of very highly trained machinists suddenly
found themselves on the job market.

--
-Ed Falk, [email protected]
http://thespamdiaries.blogspot.com/

In article <[email protected]>,
Swingman <[email protected]> wrote:
>On 11/26/2013 10:11 AM, Edward A. Falk wrote:
>
>
>Instead of rebutting the operator error in each statement above, start
>here to learn how to correctly use the software:
>
>http://www.sketchup.com/learn/videos?playlist=58

Thanks for the pointer. I'll take a look and see if there are
any videos there that I haven't seen already.

But I'm not a beginner and I stand by my original statement.

Try this exercise: make a hemisphere 1/4" in diameter.

See http://imgur.com/a/E3J4p for two hemispheres I made in Sketchup.
One was 0.125" in radius and the other was 125" in radius. I used the
exact same technique to make each of them. I was using Sketchup 8.

I've tried it using different techniques in the past, and had
different results, but they were still wrong.

If you can create this shape at 1/4" scale, I'd be interested in
finding out how you did it. I suppose if you're more persistent than
I was, you'll find a way. But as far as I know, the only way is to
make it larger, then shrink it down.

And even if you do find a way, it doesn't invalidate my previous
point that working scale matters in Sketchup, and I don't
know why that would be.

--
-Ed Falk, [email protected]
http://thespamdiaries.blogspot.com/

In article <[email protected]>,
Swingman <[email protected]> wrote:
>
>What techniques did you use and what was the error/problem?
>
>I'm assuming you used the "follow me" tool and two concentric circles to
>draw your sphere?

I used a circle as the path, and a 1/4 circle as the shape that was
to follow the path.

I used whatever the default number of segments was for the circles.

The *only* difference between the two objects was the size. .125" vs
125".

--
-Ed Falk, [email protected]
http://thespamdiaries.blogspot.com/

Richard wrote:
>
> On 11/25/2013 9:24 AM, jim wrote:
>
> > First of all most of the examples of precision that have
> > been given involve no 3d modeling at all. And the rest
> > appear to be at best 2d modeling (e.g.. a lathe profile).
>
> Huh?
> I guess you didn't check out my offerings?
>
> http://www.home.earthlink.net/~cavelamb/draft.htm
>
> Lofted to .01 inch, since traditional nail in the floor
> lofting considered 1/8th inch superb fairing.

I did look. And its nice work.
But you aren't claiming that you took
a 3d model and produced a part held to tenth
accuracy. If you can achieve .01" accuracy in
manufacturing that hull to match the 3d model,
that would be extraordinary
accuracy.

On Sun, 24 Nov 2013 18:22:26 -0600, jim <"sjedgingN0Sp"@[email protected]>
wrote:

>
>
>[email protected] wrote:
>>
>> On Sun, 24 Nov 2013 17:08:14 -0600, jim <"sjedgingN0Sp"@[email protected]>
>> wrote:
>>
>> >
>> >
>> >[email protected] wrote:
>> >
>> >> >
>> >> >People have been making things flat or round to that level of
>> >> >precision for ages.
>> >>
>> >> Flat and round (spherical) are trivial problems and as you note it's
>> >> been done for ages, at least since the middle ages.
>> >
>> >And there isn't much advantage in having a
>> >CAD model for those shapes.
>>
>> There isn't much reason to have a CAD model for a board, either, but
>> when you want to put a few dozen of them together, having a CAD model
>> gets rather interesting.
>> >
>> >
>> >> Other shapes are
>> >> more difficult, as is size.
>> >
>> >And it is doubtful there is anyone reading this who
>> >is cutting complex shapes from CAD models with precision
>> >held to tenths.
>>
>> Huh??? Have you ever heard of a mirror, or lens, system? Please
>> explain your statement?
>
>How many have you modeled in CAD and then manufactured
>to within tenth of the designed part?

You still make no sense. Are you saying that precision machining
doesn't require the same level of modeling that sloppier work does?
Really?

On 11/25/2013 1:17 PM, Leon wrote:
> On 11/25/2013 12:56 PM, Swingman wrote:
>> On 11/25/2013 12:34 PM, Leon wrote:
>>> I think the biggest problem with this whole thread is that the OP posted
>>> to wood working and metal working. His first item on his wish list was
>>> for wood boards and followed by stuff you make at home. He had the
>>> knowledge of 2D CAD programs so he was not totally ignorant of what to
>>> use but IMHO he wanted to do 3D for, most likely, less than extreme
>>> resolution drawings.
>>
>>
>> My bet is that the OP would be much more than perfectly happy with this
>> for his simple "3-D metal" drawings:
>>
>> https://lh3.googleusercontent.com/-nUVUXF4Ods0/UpOS_ypsf_I/AAAAAAAAUys/V6amC_suz40/s1440/Untitled.jpg
>>
>>
>>
>> :)
>
> And for the most part a majority in this thread! LOL. There are a few
> that may not be and rightfully so but just because I drive a Maserati
> does not mean I use it to it's limits. The Camry works just fine and in
> many practical ways out performs the Maserati.


LOL ... just ragging on you a bit, Bubba. ;)

--
eWoodShop: www.eWoodShop.com
Wood Shop: www.e-WoodShop.net
google.com/+KarlCaillouet
http://www.custommade.com/by/ewoodshop/
KarlCaillouet@ (the obvious)

On 2013-11-25, Leon <lcb11211@swbelldotnet> wrote:
> On 11/25/2013 1:00 PM, Swingman wrote:
>> On 11/25/2013 12:52 PM, Leon wrote:
>>
>>> Understood, I was talking more about the actual drawn dimension having
>>> limitations to their resolution.
>>
>> Like this:
>>
>> https://picasaweb.google.com/lh/photo/BlpE8eDGxPRV1nIUL5oqrdMTjNZETYmyPJy0liipFm0?feat=directlink
>>
>>
>> ;)
>>
>>
>
>
> No, can you think/tell me what that converts to as a fraction off the
> top of your head? LOL My calculated industries calculator can't
> either. ;~)
>
> I like to see fractions, on my drawings, that I can actually come close
> to reproducing. ;~)

That is a difference in measurement techniques and machine
design. Most machine tools have dials which read on 0.001" (or finer
for some machines), but in decimal format anyway.

Way back when, machinists worked to 1/128" at best (the Vernier
calipers would measure to that, while scales were marked to 1/64" at
best. But then, to make a running fit in a bearing, they would use
inside calipers and outside calipers to transfer measurements from one
to the other. Bore the bearing hole, take the measurement with an
inside caliper, transfer that measurement to an outside caliper (by
closing one onto the other by feel -- these had and have no markings)
and then machine the shaft to fit the bearing by slowly removing metal
until the outside calipers just slide over it with the right "feel".
(the calipers will spring a bit, so you need to learn what the right
feel is.)

These days, you purchase the shaft, measure it with a micrometer
to be sure that it is what it is claimed to be, (in decimal fractions of
an inch), make a trial bore with the cross-feed dial on the lathe
zeroed, measure the bore it produced, subtract that from the desired
size, divide by two (since most machine's cross-feeds are calibrated in
radius, not diameter) amd for rough work, just set it and bore. If you
need more precision, you approach the final cut in finer cuts, so set
that your last cut will be the same depth as the others, measure as you
approach it to be sure.

And (on a regular lathe, if you want even finer precision, you set
up a toolpost grinder, set the compound at an angle which gives you
1/10th the measurement infeed (5.7392 degrees, but you are likely to
only set it near to 5.75 degrees given the accuracy of the compound's
built-in protractor, and sneak up on the final dimensions. At last with
surface grinding, you don't have the degree of spring that you do with
normal turning.

And -- if you need even more precision, you bore and grind to
just under size, and then use a roller burnishing tool to mash the
surface down to a smoother finish at the desired measurement.

Or -- you use lapping to get that final finish and dimension.

The above is how *I* would approach greater and greater
precision on my machines.

This is how it could be done on a manual machine -- especially
one in a home hobby workshop (such as mine). CNC changes the game
somewhat. But -- the whole time you are working with tools and
instruments which read and are set in decimal factions of an inch, so
there is never a need to convert something like your 144.531250" to
144 & 17/32", and you never *think* in fractional inches. If you did, you
would be reaching for a calculator all the time. Maybe you buy your
shafting in fractional sizes, such as 0.500" or 0.375" or 0.125". Yes,
these are fractional sizes, but you *think* of them in decimal inches.

BTW The conversion with my scientific calculator (HP 15C) is done
with no problems -- discard the integer inch part, multiply the
decimal faction by the largest likely denominator (64), see that
it reads an even number, so multiply by two (converting to 32nds
instead of 64ths and get an odd precise integer number, so you
are there. Then add back the integer part of the overall
dimension once you have your fractional part right.

There are *some* digital calipers which will read in both
decimal factions of an inch, and in the nearest fractional inch size --
but you are unlikely to find a machinist using one of these for the
fractional readings -- which are, after all, just a "nearest fractional
size", not a "true reading", or you would wind up needing it to display
at least down to 1/1024th of an inch (to be close to the metalworking
basic of 1/1000" -- in some fields called a "mil" -- such as in the pin
layout dimensions for integrated circuits in electronics -- useful for
designing printed circuit boards. Some few of us got into metalworking
from the electronics field (as did I), but we seldom mention "mils" as
it confuses those measuring in mm (Millimeters -- a very different unit.

I've seen these "fractional reading" digital calipers, but never
been tempted to buy them. I just don't *think* in fractional inches
most of the time. Some few places, it is convenient. 16 Ga steel is
very close to 1/16", so I can convert that to 0.0625" and be close
enough to tell 16 ga from other sizes. (And no, that does not work
anywhere else, as the larger the gauge number, the thinner the metal.
This is related to how it is formed, progressively rolled thinner and
thinner, so it is just a lucky crossover point -- and where the limits
of my sheet metal brake and shear happen to be, so it is easy to check
whether I should try the sheet metal in those tools or not.

Enjoy,
DoN.

P.S. Not sure why I am bothering to post in this cross-posted
argument, but at least it is metalworking related, not
political. :-)

--
Remove oil spill source from e-mail
Email: <[email protected]> | (KV4PH) Voice (all times): (703) 938-4564
(too) near Washington D.C. | http://www.d-and-d.com/dnichols/DoN.html
--- Black Holes are where God is dividing by zero ---

On 2013-11-25, jim <"sjedgingN0Sp"@m> wrote:
>
>
> Jim Wilkins wrote:

[ ... ]

>> http://www.mmsonline.com/articles/getting-to-submicron-accuracy
>> "The axis position feedback system uses a 0.5-nanometer scale to
>> reliably track axis motion commands programmable in steps as small as
>> 10 nanometers."
>
> Yes that machine should be able to cut 3d parts so they match
> the 3d computer geometry to within a tenth.
> However, the CAD model of the part can be made a million times more
> accurate than even that machine can manufacture.
>
> I didn't say there were no way to produce complicated 3d
> parts that are within a tenth of the 3d CAD model.
> I said that I doubt anyone reading this was doing that. You
> still haven't changed my mind.
>
>
>
>>
>> I've watched a large aspherical Germanium infrared camera lens being
>> diamond-turned to a mirror-like submicron finish on a CNC lathe.
>
> Turning something on a lathe doesn't need a 3d model.
> That is not 3d machining.

Turning an *aspherical* lens does need a model, and a very
precise and mathematically complex one at that, to cause it to focus
where it should. And you can't check a Germanium lens by the techniques
used for visible-light lenses -- they are opaque to visible light, so
you want it cut right the first time. Same applies to silicon lenses.
I've seen both used in various experimental Infrared cameras.

> And watching someone else do it doesn't count as doing.

He did not say that he was watching someone else do it. He was
watching the *machine* do it. No *human* does it with CNC. At best
s/he feeds the data to a program which generates the motions necessary
to produce the surface to feed to the CNC machine tool.

Enjoy,
DoN.

--
Remove oil spill source from e-mail
Email: <[email protected]> | (KV4PH) Voice (all times): (703) 938-4564
(too) near Washington D.C. | http://www.d-and-d.com/dnichols/DoN.html
--- Black Holes are where God is dividing by zero ---

Leon wrote:
>
> A bit off topic, I checked the outside temp a few minutes ago,
> 42.51232367 degrees F.


Traceable to NIT?


--
Anyone wanting to run for any political office in the US should have to
have a DD214, and a honorable discharge.

On 11/25/2013 11:00 AM, Swingman wrote:
> On 11/25/2013 10:47 AM, Leon wrote:
>> Now if you are talking about a higher degree of resolution, I would a
>> agree that Sketchup begins to round after the fourth digit right of the
>> point. .0001
>
> Only for presentation, and depending upon the resolution you have set.
>
> For dimensional computations, SketchUp still uses its internal accuracy,
> the same as AutoCAD.

Here, do this:

Open SU, go to Go to Window|Model Info|Units|Fractional and choose 1/64"
or whatever Format you desire .

Now, draw a rectangle of any size using the rectangle tool

Select the rectangle and right click Area|Selection

You will see a number representing the area of the rectangle you
selected to .000000 precision.

--
eWoodShop: www.eWoodShop.com
Wood Shop: www.e-WoodShop.net
google.com/+KarlCaillouet
http://www.custommade.com/by/ewoodshop/
KarlCaillouet@ (the obvious)

Leon wrote:
>
> On 11/25/2013 11:23 AM, jim wrote:
> >
> >
> >>
> Snip
>
> >>>
> >>> A program like Sketchup caters to people who want to
> >>> model something that looks good without paying much attention
> >>> precise numbers. But that doesn't mean it is sloppy. It just
> >>> means it is not as easy to hit the exact numbers you may want as
> >>> in other programs that cater to people who want models driven
> >>> by precise numerical inputs instead of mouse actions.
> >>>
> >>
> >> I'm going to take exception to your wording in your last paragraph.
> >> Maybe I misunderstood.
> >>
> >> I was an AutoCAD user for about 8 years, other CAD programs since 1986.
> >>
> >> Anyway I am a furniture designer and builder. I have completely
> >> converted over to Sketchup.
> >>
> >> Now where I might be confused with your wording is that if I draw
> >> something that is 4" long it is precisely 4" If I draw 4.015625, I get
> >> a line that is 4 1/64" long, precisely.
> >>
> >
> > Yes. I said you can do it if you want to, but the program
> > is obviously targeted at people who want to use the mouse
> > for input.
>
> What gives you that thought.

I looked at their promotional videos. I didn't see anything
showing off its abilities to make numerically driven
models. It looks like it may be okay for cabinet work, but
what about something like making the scroll on a violin?

http://www.gussetviolins.com/untitled-1.jpg
http://t1.gstatic.com/images?q=tbn:ANd9GcQKPv8gAgVzHKvZYp10WE4HY1GyHkmZsqZOTP-UKN7lYyduBV9mZg