Crosscut Sled--What did I do wrong?

In article <[email protected]>, Ba r r y
<[email protected]> wrote:

> If it's not the flex that Leon suggests, maybe the runners aren't
> square to the blade slot?

Or maybe the blade isn't square to the miter slots...

In article <[email protected]>, Leon
<[email protected]> wrote:

> I hope it is not.. :~) Maybe parallel is what we are looking for here.

Oops. Yeah, parallel, that's it...

;-)

"Daniel Grieves" <[email protected]> wrote in message news:[email protected]...
> Having read so much about how useful a good crosscut sled was, I finally
> built myself one this weekend. I followed the basic instructions described
> here:
>
> http://www.imaging.robarts.ca/~amulder/wood/j.sled/
>
> The base is 3/4 inch birch plywood. The front & back are 2x4 common lumber.
> The runners are birch plywood slices, carefully taped to fill the slot and
> minimize wiggle. The table seems to slide smoothly and easily over the
> blade but when I went to make a few cuts with it (3/4" cherry, not a problem
> for my saw usually) the blade bound and wanted to kick the whole thing back
> at me.
>
> What was my mistake?
> Thanks in advance,
> Dan Grieves
>


Did you check the speed of feeding and proper blade for crosscutting?

Ok, first of all...Thanks to everyone who took the time to respond. Here's
what I can gather from your various responses:

1) Make sure my saw blade is parallel to the mitre guage slots. Is there a
more accurate way to do this than just building a simple T-square type thing
that I would ride in the slot and make sure it touches the saw blade equally
at all points?

2) Double-check that there's no play in my runners. Will do.

3) If 1 & 2 don't eliminate the problem, I will replace the 2x4 with
something more stable to prevent the sled from flexing.

4) If 3 doesn't work, add a top to provide even more stability. I'm
guessing it would have to be something pretty hefty (but clear) to be
workable.

5) I guess I'm a little confused on 1 point. I thought the design of the
sled was to hold the stock against the front but Larry made it sound like
the wood runs against the back edge. Which is correct? (When building my
sled, I only checked the front board for perpendicularity to blade.)

Thanks again,
Dan

That dial indicator is on sale in the stores right now for $6.99. A nice
magnetic base is just a little more.

:)



"Chuck Hoffman" <[email protected]> wrote in message
news:[email protected]...

> I bought a cheap ($13.00) dial indicator from Harbor Freight...

In article <[email protected]>, [email protected]
says...
> 5) I guess I'm a little confused on 1 point. I thought the design of the
> sled was to hold the stock against the front but Larry made it sound like
> the wood runs against the back edge. Which is correct? (When building my
> sled, I only checked the front board for perpendicularity to blade.)
>
Terminology problem. To you, and to me, the "front" is the fence
nearest you/me. To Larry, and most others, it's the fence furthest
away.

--
Homo sapiens is a goal, not a description

On Wed, 10 Nov 2004 19:33:23 -0600, Ray Aldridge
<[email protected]> wrote:

>On Tue, 09 Nov 2004 18:16:10 +0000, Mark Jerde wrote:
>
>>
>> Either front or back is fine. In some ways it makes more sense to be
>> pushing everything forward... ;-)
>
>I don't think I understand this. Unless the bed of the sled is very
>narrow, if you put the workpiece against the back of the sled, aren't you
>going to be hanging over the blade? That would make me nervous. And if
>the bed is wide enough to accomodate larger workpieces, isn't a lot of
>the sled going to be hanging precariously off the front of the table
>before you make the cut?


I think we should clarify terms. The front of my saw is the part that
the operator's belt buckle hits when cutting. The front fence of my
sled is the fence that gets to the outfeed table first when cutting.
If the sled is completely sitting on the saw, the rear fence is
nearest the front of the saw.

When I make a sled, I rarely square the front fence, only the rear.
The front fence usually exists only to stiffen the sled. Some of my
smaller sleds don't even have a front fence.

That said, I just about always cut with the work held against the rear
(reference) fence, pushing it through the blade. Therefore I think
Ray and I are on the same page, I don't know which fence Mark is
calling the "front" fence. <G>

Barry

All kinds of dancing around this one, but this answer is incorrect in one
important aspect.

Blade parallel to the miter slot is the first problem. This can cause the
blade to bind, even though it's going to produce a square cut. Are you
lifting splinters from your plywood? one of the sure signs of non-parallel
on a tablesaw or heel on a radial.

If you have your runner(s) tight, make sure they're tight all the way
through the cut, though it makes no difference in the world if they are
tight in the miter slot. *What makes a difference is that it references one
or the other side consistently.* This means straight, and I mean straight
as in no light when you set it on your reference. Some sled builders
recommend deliberately undersized runners on either side, pinching the sled
by riding the inside of the slots or out. Keeps binding to a minimum by
providing a bit of dust clearance.




"Larry Jaques" <novalidaddress@di\/ersify.com> wrote in message
news:[email protected]...
> On Mon, 8 Nov 2004 15:59:16 -0800, "Daniel Grieves"
> <[email protected]> calmly ranted:
>
> >Having read so much about how useful a good crosscut sled was, I finally
> >built myself one this weekend. I followed the basic instructions
described
> >here:
> >
> >http://www.imaging.robarts.ca/~amulder/wood/j.sled/
> >
> >The base is 3/4 inch birch plywood. The front & back are 2x4 common
lumber.
> >The runners are birch plywood slices, carefully taped to fill the slot
and
> >minimize wiggle. The table seems to slide smoothly and easily over the
> >blade but when I went to make a few cuts with it (3/4" cherry, not a
problem
> >for my saw usually) the blade bound and wanted to kick the whole thing
back
> >at me.
> >
> >What was my mistake?
>
> IF your sled runs fine with the blade up + no wood, and there is no
> slop in the runners, and the blade is new or very sharp: Most
> probably, you didn't hold the wood firmly against the back fence or
> didn't hold it down, perpendicular to the blade. Either will cause
> binding.

I still have those feeler gages for those spark plug things we used to
change all the time in cars. If I care how far off is off.

Use your combo square riding the slot. Touch good, no touch bad, it's a
go/no go situation, since any error is bad.

"Dave" <[email protected]> wrote in message
news:1F8kd.20953$5K2.11374@attbi_s03...
> That dial indicator is on sale in the stores right now for $6.99. A nice
> magnetic base is just a little more.
>
> :)
>
>
>
> "Chuck Hoffman" <[email protected]> wrote in message
> news:[email protected]...
>
> > I bought a cheap ($13.00) dial indicator from Harbor Freight...
>
>

If I understand you correctly, you are pushing the wood against the front
side of the sled. Before you do steps 1 to 4, try putting the stock to be
cut against the back of the sled. Closest to where you stand. That is the
correct place. Of course check the back side for perpendicularity to the
blade.

HTH,

Dave

> 5) I guess I'm a little confused on 1 point. I thought the design of the
> sled was to hold the stock against the front but Larry made it sound like
> the wood runs against the back edge. Which is correct? (When building my
> sled, I only checked the front board for perpendicularity to blade.)
>
> Thanks again,
> Dan

On Tue, 9 Nov 2004 08:48:57 -0800, "Daniel Grieves"
<[email protected]> calmly ranted:

>Ok, first of all...Thanks to everyone who took the time to respond. Here's
>what I can gather from your various responses:
>
>1) Make sure my saw blade is parallel to the mitre guage slots. Is there a
>more accurate way to do this than just building a simple T-square type thing
>that I would ride in the slot and make sure it touches the saw blade equally
>at all points?

If you have a dial indicator, you can mount it to the miter gauge
so it touches the blade. Check the reading at the front, rotate the
blade to the back, and check the reading again. Ed Bennett, one of
the Wreckers here, builds a fancy set for checking all the tools in
your shop, butcha gotta have a crowbar if you're like me. The $6
Harbor Freight indicator works just fine. You choose. The video he
has put together is great, and a really good value: $1.96 delivered
to your door. http://www.ts-aligner.com/newindex.htm


>2) Double-check that there's no play in my runners. Will do.

Good.


>3) If 1 & 2 don't eliminate the problem, I will replace the 2x4 with
>something more stable to prevent the sled from flexing.

I used 1/2" Baltic Birch ply and put a piece of 1x4" oak on both ends.
It flexes only when I put a 6-8' stud on there to hack off. <g>


>4) If 3 doesn't work, add a top to provide even more stability. I'm
>guessing it would have to be something pretty hefty (but clear) to be
>workable.

If you want to be EU safe and don't want to see what you're cutting.
(Pretty soon they'll have thought police there, too.)


>5) I guess I'm a little confused on 1 point. I thought the design of the
>sled was to hold the stock against the front but Larry made it sound like
>the wood runs against the back edge. Which is correct? (When building my
>sled, I only checked the front board for perpendicularity to blade.)

So we're clear, I call the end which hits the saw first the front.

Because it's cut last, the back is closer to your body while feeding
the sled through. I nestle the board up against the backer board
closest to me. The front board is there to hold the two cut halves of
the sled together. The back is what should be aligned with the blade.

Did that help clarify things for you?

I've noticed a couple times that vibration in the saw (Dina can't
pass the -flat- nickel test due to an old jaw injury on her motor
pulley, but it's only about 1/4" off. ;) caused the board to float
out about 1/8" and I got a bind when I started the cut. I pay more
attention now to both finger and board placement.


-------------------------------------------------------------
* * Humorous T-shirts Online
* Norm's Got Strings * Wondrous Website Design
* * http://www.diversify.com
-------------------------------------------------------------

"Chad Bender" <[email protected]> wrote in message
news:[email protected]...

> One problem
> I had with the wooden runners was that they were very slightly warped, or
> curved, so if the sled was square at the front of the cut, it was slightly
> off by the end. This did cause some binding.

Maybe this is too obvious a question. Did you mill the wood before using it
as runners?

Bob

Dave wrote:
> If I understand you correctly, you are pushing the wood against the
> front side of the sled. Before you do steps 1 to 4, try putting the
> stock to be cut against the back of the sled. Closest to where you
> stand. That is the correct place.

Either front or back is fine. In some ways it makes more sense to be
pushing everything forward... ;-)

IIRC Kelly Mehler's table saw book shows both front and back aligned
crosscut sleds. I don't have the book checked out from the library so I
can't check for sure. ;-)

My understanding is the Europeans favor the front models in both jigs and
sliding table construction, while US woodworkers favor the back.

-- Mark

I recommend a harder material for the runners. Oak, Maple, Steel. I am
guessing your runners are flexing and causing your sled to not go in a
straight parallel line to the blade. It will work better also if you mount
the runners into a dado so that there will be no flexing.


"Daniel Grieves" <[email protected]> wrote in message
news:[email protected]...
> Having read so much about how useful a good crosscut sled was, I finally
> built myself one this weekend. I followed the basic instructions
> described here:
>
> http://www.imaging.robarts.ca/~amulder/wood/j.sled/
>
> The base is 3/4 inch birch plywood. The front & back are 2x4 common
> lumber. The runners are birch plywood slices, carefully taped to fill the
> slot and minimize wiggle. The table seems to slide smoothly and easily
> over the blade but when I went to make a few cuts with it (3/4" cherry,
> not a problem for my saw usually) the blade bound and wanted to kick the
> whole thing back at me.
>
> What was my mistake?
> Thanks in advance,
> Dan Grieves
>

"Dave Balderstone" <dave@N_O_T_T_H_I_S.balderstone.ca> wrote in message
news:081120041839455012%dave@N_O_T_T_H_I_S.balderstone.ca...
> In article <[email protected]>, Ba r r y
> <[email protected]> wrote:
>
>> If it's not the flex that Leon suggests, maybe the runners aren't
>> square to the blade slot?
>
> Or maybe the blade isn't square to the miter slots...

I hope it is not.. :~) Maybe parallel is what we are looking for here.

Ba r r y wrote:
> On Wed, 10 Nov 2004 19:33:23 -0600, Ray Aldridge
> <[email protected]> wrote:
>
>
>>On Tue, 09 Nov 2004 18:16:10 +0000, Mark Jerde wrote:
>>
>>
>>>Either front or back is fine. In some ways it makes more sense to be
>>>pushing everything forward... ;-)
>>
>>I don't think I understand this. Unless the bed of the sled is very
>>narrow, if you put the workpiece against the back of the sled, aren't you
>>going to be hanging over the blade? That would make me nervous. And if
>>the bed is wide enough to accomodate larger workpieces, isn't a lot of
>>the sled going to be hanging precariously off the front of the table
>>before you make the cut?
>
>
>
> I think we should clarify terms. The front of my saw is the part that
> the operator's belt buckle hits when cutting. The front fence of my
> sled is the fence that gets to the outfeed table first when cutting.
> If the sled is completely sitting on the saw, the rear fence is
> nearest the front of the saw.
>
> When I make a sled, I rarely square the front fence, only the rear.
> The front fence usually exists only to stiffen the sled. Some of my
> smaller sleds don't even have a front fence.
>
> That said, I just about always cut with the work held against the rear
> (reference) fence, pushing it through the blade. Therefore I think
> Ray and I are on the same page, I don't know which fence Mark is
> calling the "front" fence. <G>
>
> Barry

Well, there are standards of designations for moving things but some
people don't know them and don't use them. Unfortunately when talking
about moving and non moving things one can get mixed up. I agree that
the front of the saw is where the belt buckle is cause a saw doesn't
move. OTOH, a auto moves, so the front is the part that "arrives"
first and the right side of the a car assumes the person if facing the
way the car is driven. The right side of a stream also assumes that a
person is facing downstream. Thus the front of a sled is just like
a n auto, first part to arrive (at the saw). You could also talk
about the right side of a sled but that would be asking too much.

"George E. Cawthon" wrote in message

> person is facing downstream. Thus the front of a sled is just like
> a n auto, first part to arrive (at the saw). You could also talk
> about the right side of a sled but that would be asking too much.

54 degrees.

--
www.e-woodshop.net
Last update: 11/06/04

"Mark Jerde" <[email protected]> wrote in message
news:vLXjd.101$z_4.78@trnddc07...
> Bob wrote:

> Is that a MuleCab fence? (I'm thinking of getting one.)

Sorry, I don't know, Mark. The link belongs to someone else. I just happened
to see it an thought it was useful to post here.

Bob

> one thing to check is that your 2x4 front (the one the wood rides
> against) is straight. if it's concave you could get that kind of
> binding.
>
> it really should be made of stable dry material. I gave up making them
> out of 2x. these days I make them out of baltic birch ply...
>

Kiln dried, VG doug fir. Jointed flat & square. Shellac and wax.

1/2" BB ply.

Oak runners, or Delta purchased runners, if I'm particularly lazy or in a
hurry.

Patriarch

Larry Jaques wrote:

> IF your sled runs fine with the blade up + no wood, and there is no
> slop in the runners, and the blade is new or very sharp: Most
> probably, you didn't hold the wood firmly against the back fence or
> didn't hold it down, perpendicular to the blade. Either will cause
> binding.

To help hold the wood in place I put down strips of "Skid Guard Safety Tape"
on the back and bottom of my sled. You could also glue strips of sandpaper
but I already had the self-adhesive strips. It made all the difference for
keeping the piece being cut in place.

-- Mark

On Fri, 12 Nov 2004 02:06:42 GMT, "George E. Cawthon"
<[email protected]> wrote:

>Ba r r y wrote:
>> On Wed, 10 Nov 2004 19:33:23 -0600, Ray Aldridge
>> <[email protected]> wrote:
>>
>>
>>>On Tue, 09 Nov 2004 18:16:10 +0000, Mark Jerde wrote:
>>>
>>>
>>>>Either front or back is fine. In some ways it makes more sense to be
>>>>pushing everything forward... ;-)
>>>
>>>I don't think I understand this. Unless the bed of the sled is very
>>>narrow, if you put the workpiece against the back of the sled, aren't you
>>>going to be hanging over the blade? That would make me nervous. And if
>>>the bed is wide enough to accomodate larger workpieces, isn't a lot of
>>>the sled going to be hanging precariously off the front of the table
>>>before you make the cut?
>>
>>
>>
>> I think we should clarify terms. The front of my saw is the part that
>> the operator's belt buckle hits when cutting. The front fence of my
>> sled is the fence that gets to the outfeed table first when cutting.
>> If the sled is completely sitting on the saw, the rear fence is
>> nearest the front of the saw.
>>
>> When I make a sled, I rarely square the front fence, only the rear.
>> The front fence usually exists only to stiffen the sled. Some of my
>> smaller sleds don't even have a front fence.
>>
>> That said, I just about always cut with the work held against the rear
>> (reference) fence, pushing it through the blade. Therefore I think
>> Ray and I are on the same page, I don't know which fence Mark is
>> calling the "front" fence. <G>
>>
>> Barry
>
>Well, there are standards of designations for moving things but some
>people don't know them and don't use them. Unfortunately when talking
>about moving and non moving things one can get mixed up. I agree that
>the front of the saw is where the belt buckle is cause a saw doesn't
>move. OTOH, a auto moves, so the front is the part that "arrives"
>first and the right side of the a car assumes the person if facing the
>way the car is driven. The right side of a stream also assumes that a
> person is facing downstream. Thus the front of a sled is just like
>a n auto, first part to arrive (at the saw). You could also talk
>about the right side of a sled but that would be asking too much.

damnit, now I can't find the front of my house!


We've found an interesting confusion in RV's that ties in with your
theory, though...

Most folks think of the end with the hitch as the front when towing
it, but the side with the door is the front when you're camping...

On Tue, 09 Nov 2004 01:07:32 +0000, Andy Dingley <[email protected]>
wrote:

>On Mon, 8 Nov 2004 15:59:16 -0800, "Daniel Grieves"
><[email protected]> wrote:
>
>>Having read so much about how useful a good crosscut sled was,
>
>Not from me - they're dangerous bloody things. A UK HSE inspector
>will usually throw a wobbly if he sees one too (they're having a
>downer on "emerging blade" cuts these days).
>
>Throw it away now and build a crosscut _BOX_. This is similar, but it
>has a top too. The sides are tall enough to keep your fingers away
>from the blade and there's a wide strip (often transparent) across the
>top, covering the blade from the top direction. This also helps to
>stiffen the box, avoiding the sort of flex and binding in the
>baseplate that you're getting.

... and if the problem is that his runners are flexing, the only thing he
is going to accomplish by that is adding mass to that which will be thrown
back at him.

So, how do you actually get something *into* this totally safe box? and
how do you hold anything steady with all these safety devices hanging about
the thing? I personally use a clamp to hold the piece I'm cutting, thus
accomplishing two things: 1) it makes sure the piece does not slip while
being cut and 2) it keeps my fingers safely away from the blade.


>
>You can also (if you make a box) use a baseplate of thin Masonite,
>rather than thick plywood. If this should choose to bind, the force is
>minimal and it's unlikely to lift or throw.
>
>There should be closed-ended tunnels at the ends of the slot too, so
>that the whole blade can be "swallowed" without protruding. Make the
>ends of them thick enough to survive running into the blade from time
>to time.

I've found that a simple block wood attached at the back center of the sled
accomplishes the same thing without the complexity of a "tunnel"

On Thu, 11 Nov 2004 08:19:50 -0600, "Swingman" <[email protected]> wrote:


>Maybe we should start a TS sled convention designating your rear fence, and
>my front fence, as the "near" fence?

That actually makes way too much sense.

I'll have to remember to use near and far in the future.

Barry

"Ba r r y" wrote in message

> I think we should clarify terms. The front of my saw is the part that
> the operator's belt buckle hits when cutting. The front fence of my
> sled is the fence that gets to the outfeed table first when cutting.
> If the sled is completely sitting on the saw, the rear fence is
> nearest the front of the saw.

You must be a left-handed democrat? ;>)

It's like the "near" side of a horse ... it's a matter of perspective if
you're not a horseman. Actually, I think of it just the opposite when it
comes to fences on TS sleds, The front fence is the one nearest to me that I
hold the wood against, and the rear fence is that one way over there, past
the blade.

Maybe we should start a TS sled convention designating your rear fence, and
my front fence, as the "near" fence?

Who says we don't "reach out" to each other? <g>

--
www.e-woodshop.net
Last update: 11/06/04

On Tue, 09 Nov 2004 00:13:32 GMT, "Leon"
<[email protected]> wrote:

>I recommend a harder material for the runners. Oak, Maple, Steel. I am
>guessing your runners are flexing and causing your sled to not go in a
>straight parallel line to the blade. It will work better also if you mount
>the runners into a dado so that there will be no flexing.

If it's not the flex that Leon suggests, maybe the runners aren't
square to the blade slot?

This would move the slot from side to side as the sled travels along.
With the saw shut off can the sled move smoothly over the blade for
the full travel?

I lay the runners in the slots with glue on them, lay the panel on,
place some weights, and add screws after the glue sets. The blade
slot dosen't get cut until after the face(s) are added, then the rear
face is squared to the slot and glued. The saw itself is the perfect
jig for aligning the runners.

Dadoing would add a whole bunch of extra work, in my opinion. Since I
usually make sleds and jigs when the need arises, I tend to simplify
them as much as possible. My smaller sleds don't even have a front
fence.

I've used ash, red & white oak, birch, and maple for runners. All
worked fine.

Barry

On Fri, 12 Nov 2004 06:51:02 GMT, mac davis <[email protected]>
calmly ranted:

George Cawthon said:
>>Well, there are standards of designations for moving things but some
>>people don't know them and don't use them. Unfortunately when talking
>>about moving and non moving things one can get mixed up. I agree that
>>the front of the saw is where the belt buckle is cause a saw doesn't
>>move. OTOH, a auto moves, so the front is the part that "arrives"
>>first and the right side of the a car assumes the person if facing the
>>way the car is driven. The right side of a stream also assumes that a
>> person is facing downstream. Thus the front of a sled is just like
>>a n auto, first part to arrive (at the saw). You could also talk
>>about the right side of a sled but that would be asking too much.

Goodonya, Geo.


>damnit, now I can't find the front of my house!
>
>We've found an interesting confusion in RV's that ties in with your
>theory, though...

Got a mouse in your pocket, son?


>Most folks think of the end with the hitch as the front when towing
>it, but the side with the door is the front when you're camping...

No, that's just the entrance. The front is still the front, with the
hitch. You don't call the side of the car with the door the front, do
you, silly person? Oy vay. ;)


-------------------------------------------------
- Boldly going - * Wondrous Website Design
- nowhere. - * http://www.diversify.com
-------------------------------------------------

On Mon, 8 Nov 2004 15:59:16 -0800, "Daniel Grieves"
<[email protected]> wrote:

>Having read so much about how useful a good crosscut sled was,

Not from me - they're dangerous bloody things. A UK HSE inspector
will usually throw a wobbly if he sees one too (they're having a
downer on "emerging blade" cuts these days).

Throw it away now and build a crosscut _BOX_. This is similar, but it
has a top too. The sides are tall enough to keep your fingers away
from the blade and there's a wide strip (often transparent) across the
top, covering the blade from the top direction. This also helps to
stiffen the box, avoiding the sort of flex and binding in the
baseplate that you're getting.

You can also (if you make a box) use a baseplate of thin Masonite,
rather than thick plywood. If this should choose to bind, the force is
minimal and it's unlikely to lift or throw.

There should be closed-ended tunnels at the ends of the slot too, so
that the whole blade can be "swallowed" without protruding. Make the
ends of them thick enough to survive running into the blade from time
to time.
--
Smert' spamionam

On Mon, 08 Nov 2004 17:09:04 -0800, Larry Jaques
<novalidaddress@di\/ersify.com> wrote:

>
>>Having read so much about how useful a good crosscut sled was, I finally
>>built myself one this weekend. I followed the basic instructions described
>>here:
>>
>>http://www.imaging.robarts.ca/~amulder/wood/j.sled/
>>
>>The base is 3/4 inch birch plywood. The front & back are 2x4 common lumber.
>>The runners are birch plywood slices, carefully taped to fill the slot and
>>minimize wiggle. The table seems to slide smoothly and easily over the
>>blade but when I went to make a few cuts with it (3/4" cherry, not a problem
>>for my saw usually) the blade bound and wanted to kick the whole thing back
>>at me.
>>
>>What was my mistake?


one thing to check is that your 2x4 front (the one the wood rides
against) is straight. if it's concave you could get that kind of
binding.

it really should be made of stable dry material. I gave up making them
out of 2x. these days I make them out of baltic birch ply...

On Mon, 8 Nov 2004 15:59:16 -0800, "Daniel Grieves"
<[email protected]> wrote:

>Having read so much about how useful a good crosscut sled was, I finally
>built myself one this weekend. I followed the basic instructions described
>here:
>
>http://www.imaging.robarts.ca/~amulder/wood/j.sled/

Suggestion. It looks like the "handle" is over the blade. Make it
with one either side for safer "handling".

"Andy Dingley" <[email protected]> wrote in message
news:[email protected]...

> Throw it away now and build a crosscut _BOX_. This is similar, but it
> has a top too.

I thought a picture would help. Here is a fancified version of what you are
talking about.

http://billpentz.com/woodworking/cyclone/AlHallaman/Image20.jpg

Bob

On Mon, 8 Nov 2004 15:59:16 -0800, "Daniel Grieves"
<[email protected]> calmly ranted:

>Having read so much about how useful a good crosscut sled was, I finally
>built myself one this weekend. I followed the basic instructions described
>here:
>
>http://www.imaging.robarts.ca/~amulder/wood/j.sled/
>
>The base is 3/4 inch birch plywood. The front & back are 2x4 common lumber.
>The runners are birch plywood slices, carefully taped to fill the slot and
>minimize wiggle. The table seems to slide smoothly and easily over the
>blade but when I went to make a few cuts with it (3/4" cherry, not a problem
>for my saw usually) the blade bound and wanted to kick the whole thing back
>at me.
>
>What was my mistake?

IF your sled runs fine with the blade up + no wood, and there is no
slop in the runners, and the blade is new or very sharp: Most
probably, you didn't hold the wood firmly against the back fence or
didn't hold it down, perpendicular to the blade. Either will cause
binding.

--
The State always moves slowly and grudgingly towards any purpose that
accrues to society's advantage, but moves rapidly and with alacrity
towards one that accrues to its own advantage; nor does it ever move
towards social purposes on its own initiative, but only under heavy
pressure, while its motion towards anti-social purposes is self-sprung.
- Albert Jay Nock
- http://diversify.com Web Programming for curmudgeons and others. -

On Mon, 08 Nov 2004 18:59:16 -0500, Daniel Grieves wrote:

> Having read so much about how useful a good crosscut sled was, I finally
> built myself one this weekend. I followed the basic instructions
> described here:
>
> http://www.imaging.robarts.ca/~amulder/wood/j.sled/
>
>
I constructed that a sled using those plans a few months ago. I modified
things slightly, and it works excellent (although took a few iterations to
get it working well).

I'd recommend replacing your runner material with something harder. I
started with hard maple. These worked ok, but not great. I recently
upgraded to steel bar, available at the local BORG. This has made a huge
difference in overall stiffness and ease of sliding the sled. One problem
I had with the wooden runners was that they were very slightly warped, or
curved, so if the sled was square at the front of the cut, it was slightly
off by the end. This did cause some binding.

I'd also recommend attaching a piece of 2x4 or 2x6 protruding out the
back. This is similar to the 'tunnel' someone else mentioned, but a lot
simpler. The blade goes into the 2x4, and I always know where it will
end up after a cut. I don't have to worry about visually checking where
my hand is - I can do it by feel.

Try replacing the runners, and see if that helps. A working sled is well
worth the time invested.

Chad

On Tue, 09 Nov 2004 18:16:10 +0000, Mark Jerde wrote:

>
> Either front or back is fine. In some ways it makes more sense to be
> pushing everything forward... ;-)

I don't think I understand this. Unless the bed of the sled is very
narrow, if you put the workpiece against the back of the sled, aren't you
going to be hanging over the blade? That would make me nervous. And if
the bed is wide enough to accomodate larger workpieces, isn't a lot of
the sled going to be hanging precariously off the front of the table
before you make the cut?

On Tue, 9 Nov 2004 08:48:57 -0800, "Daniel Grieves"
<[email protected]> wrote:

>Ok, first of all...Thanks to everyone who took the time to respond. Here's
>what I can gather from your various responses:
>
>1) Make sure my saw blade is parallel to the mitre guage slots. Is there a
>more accurate way to do this than just building a simple T-square type thing
>that I would ride in the slot and make sure it touches the saw blade equally
>at all points?

that's the basic idea. you also want to account for any runout in the
blade itself, though. the way to do that is to pick a spot on the
blade near the rim and mark it with a felt tip pen. use that spot for
all of your measurements. raise the blade all of the way up to
increase it's length above the table. rotate the blade so your mark is
near the front and take a measurement of the distance from the blade
to the miter slot. rotate the blade so the mark is near the back and
take another measurement. compare the two measurements.





it sounds like it's time to post my sled again on ABPW. look for it
there.

On Tue, 9 Nov 2004 16:55:21 -0500, "George" <george@least> wrote:

>I still have those feeler gages for those spark plug things we used to
>change all the time in cars. If I care how far off is off.
>
>Use your combo square riding the slot. Touch good, no touch bad, it's a
>go/no go situation, since any error is bad.

Exactly.

Barry

My way of checking that the blade is parallel to the miter gauge slot is as
follows:

MAKE SURE YOUR TABLE SAW IS UNPLUGGED WHILE PERFORMING THIS PROCEDURE.

I bought a cheap ($13.00) dial indicator from Harbor Freight, marked and
drilled a hole in the end of a 1X3 and mounted the dial indicator to it. I
clamped the 1X3/dial indicator assembly in my miter gauge (mine has a
hold-down but you can use a regular clamp) and marked a tooth on the blade
that was "set" toward the miter gauge. I held the bar of the miter gauge
tight against one side of the slot and slid the rig back and forth while
rotating the blade to make sure the dial indicator tip was in contact with
the same spot on the marked tooth both front and back

By doing this, I was able to reduce the arbor alignment error to only .003
inch. I could have gotten it closer with a little more effort but since the
blade itself had more than four times the runout, I figured that was good
enough.

I bought the dial indicator after struggling for three days...and many test
cuts...to set up my power miter box using a method similar to what you
described.

"Daniel Grieves" <[email protected]> wrote in message
news:[email protected]...
> Ok, first of all...Thanks to everyone who took the time to respond.
Here's
> what I can gather from your various responses:
>
> 1) Make sure my saw blade is parallel to the mitre guage slots. Is there
a
> more accurate way to do this than just building a simple T-square type
thing
> that I would ride in the slot and make sure it touches the saw blade
equally
> at all points?
>

Ba r r y wrote:
> On Thu, 11 Nov 2004 08:19:50 -0600, "Swingman" <[email protected]> wrote:
>
>
>> Maybe we should start a TS sled convention designating your rear
>> fence, and my front fence, as the "near" fence?
>
> That actually makes way too much sense.
>
> I'll have to remember to use near and far in the future.

In (a) table saw book(s) I have seen crosscut sleds that use the far fence.
It is my understanding that is the configuration of both crosscut sleds and
crosscut tables preferred by the Europeans.

-- Mark

On Tue, 09 Nov 2004 00:47:42 GMT, "Leon"
<[email protected]> wrote:

>
>"Dave Balderstone" <dave@N_O_T_T_H_I_S.balderstone.ca> wrote in message
>news:081120041839455012%dave@N_O_T_T_H_I_S.balderstone.ca...
>> In article <[email protected]>, Ba r r y
>> <[email protected]> wrote:
>>
>>> If it's not the flex that Leon suggests, maybe the runners aren't
>>> square to the blade slot?
>>
>> Or maybe the blade isn't square to the miter slots...
>
>I hope it is not.. :~) Maybe parallel is what we are looking for here.
>


RIGHT! <G> I'm sure both of us mean parallel.

If the blade were square to the runners or slots, I'm sure we'd get
all kinds of neat problems.

At least _I_ always know what I mean.

Barry

Bob wrote:
> "Andy Dingley" <[email protected]> wrote in message
> news:[email protected]...
>
>> Throw it away now and build a crosscut _BOX_. This is similar, but
>> it has a top too.
>
> I thought a picture would help. Here is a fancified version of what
> you are talking about.
>
> http://billpentz.com/woodworking/cyclone/AlHallaman/Image20.jpg
>
> Bob

Is that a MuleCab fence? (I'm thinking of getting one.)

-- Mark