I have steel ramps, but they are very short and suitable for my [low]
trailer only.
I am considering making ramps from wooden boards. Specifically,
picture a ramp that looks like a letter I in cross section. The wide
part of the I is a 2x8. On the top and bottom of the I, there would be
2x4s. The "I", of course, would be laid flat for use.
Here's the ascii graphic:
. .
|==========|
~ ~
The 2x4s would be screwed to the 2x8 with wood screws, and reinforced
with glue.
My question is, what would be the strength of this ramp if it was,
say, 8 ft long. Specifically, how much load could I place in the
middle for some reasonably low deflection (like 1-2 inches).
thanks
i
sOn 2007-10-25, dpb <[email protected]> wrote:
> Ignoramus20839 wrote:
>> On 2007-10-25, dpb <[email protected]> wrote:
>>> Ignoramus20839 wrote:
>>>> On 2007-10-25, Chris Friesen <[email protected]> wrote:
>>>>> Ignoramus20839 wrote:
>>>>>
>>>>>> My question is, what would be the strength of this ramp if it was,
>>>>>> say, 8 ft long. Specifically, how much load could I place in the
>>>>>> middle for some reasonably low deflection (like 1-2 inches).
>>>>> Using spruce pine and ignoring the 2x8, the sagulator gives a deflection
>>>>> of .7" for 500lbs of load in the center of a single 8' ramp.
>>>>>
>>>> OK, this is great. What does your sagulator say about 1000 lbs load?
>>> Google "sagulator" and experiment to your heart's content...
>>>
>>
>> I thought that sagulator was a PC program. It is great! I have it
>> bookmarked and am now experimenting!!!
>>
>> Looks like with 2x4x, the deflection of a 1,000 lbs load in the middle
>> will be about 2 inches, which is too much.
>>
>> However, with 2x6s, the deflection will only be 0.36 inches, and 0.7
>> inches with 2,000 lbs center load.
>>
>> So, it seems, that a ramp made to the shape of letter I, could easily
>> let me deal with 2,000 lbs wheeled loads. (such as a dolly on casters)
>
> Well, when you're dealing with that kind of loads, don't forget the
> supporting ends, joint strength and fasteners, point loading of a caster
> on the 2x ramp, the downward force of the load back down the ramp
> running over whatever is in the way, the load limit on a truck tailgate,
> etc., etc., etc., ...
>
Well, absolutely. Plus the 2x8 may crack on the middle under such a
load.
i
"Ignoramus7291" wrote
>
> I have a trailer that can carry a lot more than 2,000 lbs. I made it
> myself, kind of.
>
> http://igor.chudov.com/projects/Homemade-Trailer-With-M105A2-Bed/
>
> It can carry about 4k lbs.
>
After viewing your very impressive trailer build, I have two very irreverant
thoughts.
The first is a mental picture of those crummy trailer kits sold at the borg
and Harbor Freight. You know, the light weight trailers that come in two
big cardboard boxes. Lots of pieces that you bolt together.
What you built is twenty times heavier, a hundred times more sturdy and
million times more classy that those cheap kits.
The second thought is that cammo paint job looks really good on the trailer.
When are you going to paint the truck to match the trailer?
On Oct 25, 5:39 pm, Ignoramus20839 <ignoramus20...@NOSPAM.
20839.invalid> wrote:
> I thought that sagulator was a PC program. It is great! I have it
> bookmarked and am now experimenting!!!
>
> Looks like with 2x4x, the deflection of a 1,000 lbs load in the middle
> will be about 2 inches, which is too much.
>
> However, with 2x6s, the deflection will only be 0.36 inches, and 0.7
> inches with 2,000 lbs center load.
>
> So, it seems, that a ramp made to the shape of letter I, could easily
> let me deal with 2,000 lbs wheeled loads. (such as a dolly on casters)
>
> i
While you are playing with the design, think about a couple of blocks
you could put between about the middle of the ramp and the ground. If
you had a block in the middle of the span, it would be like two 4 foot
ramps in series. And I think the capacity would be much higher. So
you could use you original design which would be lighter to set in
place.
Dan
On Oct 25, 7:22 pm, Ignoramus20839 >
> Good point. It is not trivial, though, to add that middle support that
> would be usable with different heights. But it is a very good thought,
> and a solvable problem.
>
> i
You don't have to have it height adjustable. Just a reasonable size
so it will fit under the ramp. If the ramp is being used for a low
thing, the support may be close to the high end, and the unsupported
length a two foot span and a six foot span. If it is being used on a
very high thing, the support may be close to the ground end, and
again you have a two foot and six foot span. But when you play with
the program you will see a six foot span is much better than an eight
foot span.
Of course cutting in to two four foot spans is even better, and those
aluminum support jacks look like a nice solution.
Dan
On Oct 25, 3:10 pm, "[email protected]" <[email protected]> wrote:
> On Oct 25, 7:22 pm, Ignoramus20839 >
>
> > Good point. It is not trivial, though, to add that middle support that
> > would be usable with different heights. But it is a very good thought,
> > and a solvable problem.
>
> > i
>
> You don't have to have it height adjustable. Just a reasonable size
> so it will fit under the ramp. If the ramp is being used for a low
> thing, the support may be close to the high end, and the unsupported
> length a two foot span and a six foot span. If it is being used on a
> very high thing, the support may be close to the ground end, and
> again you have a two foot and six foot span. But when you play with
> the program you will see a six foot span is much better than an eight
> foot span.
>
> Of course cutting in to two four foot spans is even better, and those
> aluminum support jacks look like a nice solution.
>
> Dan
Using deflection as a criterion for beam design is not to be condoned.
The beam MUST be designed with an allowable BENDING stress in the top
and bottom flange of the beam.
Once this stress is at an acceptable level can the design be checked
for deflection and, if too large, the beam be made stronger TO REDUCE
THE DEFLECTION.
Starting with deflection one has no idea what the bending stress is
and whether it has exceeded the allowable limit.
Since I generally do not design in wood..... if someone will supply
the info on type and grade of lumber, and allowable bending stress
(from a building code, perhaps) I would let you know the load
capacity.
Wolfgang
>
> Looks like with 2x4x, the deflection of a 1,000 lbs load in the middle
> will be about 2 inches, which is too much.
>
> However, with 2x6s, the deflection will only be 0.36 inches, and 0.7
> inches with 2,000 lbs center load.
>
> So, it seems, that a ramp made to the shape of letter I, could easily
> let me deal with 2,000 lbs wheeled loads. (such as a dolly on casters)
>
> i
Why not nix the idea of the 2X4's on the sides and do this instead. Make
your own metal ramp ends that you fit to the ends of the ramps and then rout
slots on the underside of the boards where you run a couple of 1/4 or 3/8
rods that are fastened to the metal ends. This way the lumber will be in
compression, and the steel will restrain the wood from flexing too much.
I did something similar to some saggy rafters and was able to jack the whole
roof straight.
--
__
Roger Shoaf
Important factors in selecting a mate:
1] Depth of gene pool
2] Position on the food chain.
On Oct 25, 2:22 pm, Ignoramus20839 <ignoramus20...@NOSPAM.
20839.invalid> wrote:
...
> Good point. It is not trivial, though, to add that middle support that
> would be usable with different heights. But it is a very good thought,
> and a solvable problem.
Car jack stands work well for this as long as you tie the ramps to the
vehicle and use a crosswise plank between the stands and the ramps.
The ramps may twist if supported only by the narrow stand tops, and
when the vehicle sinks from the load, the ramp ends lift off the
ground and slide. Put some tiedown eyes on the sides of the ramp.
Jim W
> Why not nix the idea of the 2X4's on the sides and do this instead. Make
> your own metal ramp ends that you fit to the ends of the ramps and then rout
> slots on the underside of the boards where you run a couple of 1/4 or 3/8
> rods that are fastened to the metal ends. This way the lumber will be in
> compression, and the steel will restrain the wood from flexing too much.
I like this idea, though the earlier idea of bolting on angle is
probably easier.
Alternatively, consider changing from box store softwood to a locally
milled rough hardwood like oak or ash. The wood itself is stiffer and
you'll gain a little more stiffness from it being thicker (close to a
full 2").
--Glenn Lyford
"Ignoramus7291" <[email protected]> wrote in message
news:[email protected]...
> The axle is 6,000 lbs rated. I bought it new. The entire trailer
> weighs less than 2,000 lbs. My estimate is about 1,700 lbs.
>
> i
The axel rating is only part of the equation, you also can't exceed the tire
rating nor the rating of the vehicle pulling the trailer.
Any one of those specs exceeded and the Highway Patrol can side line the
trailer until the load can be made legal and weight tickets like this are
priced by the pound.
--
Roger Shoaf
About the time I had mastered getting the toothpaste back in the tube, then
they come up with this striped stuff.
<[email protected]> wrote in message
news:[email protected]...
>
> I like this idea, though the earlier idea of bolting on angle is
> probably easier.
>
As I sse the problem with the angle idea is that when the ramp is loaded,
the bolts you use to secure the angle to the wood will want to twist in the
wood, ant that would as I see it be the start of a failure.
By using the steel on the underside as I suggested the sag would be limited
to the ability of the steel to streach against the unwillingness of the wood
to compress against the end grain like a wall stud.
You could induce a little preload when welding the rods to the end caps if
you flipped the ramp upside down and between two fulcrum points. If you
welded one end, and then placed a weight on the center the wood would flex
down, (Actually "up" in its usual orientation.) and then you could weld the
other end. When the weight was released, the rods would already be in
tension.
--
Roger Shoaf
About the time I had mastered getting the toothpaste back in the tube, then
they come up with this striped stuff.
> Alternatively, consider changing from box store softwood to a locally
> milled rough hardwood like oak or ash. The wood itself is stiffer and
> you'll gain a little more stiffness from it being thicker (close to a
> full 2").
>
> --Glenn Lyford
>
Ignoramus7291 wrote:
> On 2007-10-26, Ignoramus7291 <[email protected]> wrote:
>
>>I love the camo job, yes, and here's my dilemma. I feel like I need to
>>sand and paint over some spots, but I do not know how to prevent the
>>pattern.
>
>
> I mean, how to keep the pattern, I do not know what I was thinking.
>
> i
The paint scheme will be found in TM 43-0139.
http://www.dmkf.dk/Filer_manualer/Camo/TB%2043-0139%20Color%20generel.pdf
Kevin Gallimore
----== Posted via Newsfeeds.Com - Unlimited-Unrestricted-Secure Usenet News==----
http://www.newsfeeds.com The #1 Newsgroup Service in the World! 120,000+ Newsgroups
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On Thu, 25 Oct 2007 12:10:00 -0500, "Pete C." <[email protected]>
wrote:
>
>For what I expect would be better strength, rigidity and protection from
>potential defects in dimensional lumber, try making a glued and screwed
>box beam. Something like a top surface layer of three layers of 3/4"
>plywood, two or three 2x4 members inside the box, and another layer of
>3/4" ply on the bottom.
A box beam of plywood and 2X's would make an excellent ramp, but
you've got the functions of the plywood and sawn lumber reversed. The
plywood should be the vertical webs and the 2X's the top and bottom
plates. The 2X's carry the tension and compression loads; the plywood
resists the shear between the tension and compression members.
--
Ned Simmons
Ignoramus20839 wrote:
> My question is, what would be the strength of this ramp if it was,
> say, 8 ft long. Specifically, how much load could I place in the
> middle for some reasonably low deflection (like 1-2 inches).
Using spruce pine and ignoring the 2x8, the sagulator gives a deflection
of .7" for 500lbs of load in the center of a single 8' ramp.
Chris
Ignoramus20839 wrote:
>
> sOn 2007-10-25, dpb <[email protected]> wrote:
> > Ignoramus20839 wrote:
> >> On 2007-10-25, dpb <[email protected]> wrote:
> >>> Ignoramus20839 wrote:
> >>>> On 2007-10-25, Chris Friesen <[email protected]> wrote:
> >>>>> Ignoramus20839 wrote:
> >>>>>
> >>>>>> My question is, what would be the strength of this ramp if it was,
> >>>>>> say, 8 ft long. Specifically, how much load could I place in the
> >>>>>> middle for some reasonably low deflection (like 1-2 inches).
> >>>>> Using spruce pine and ignoring the 2x8, the sagulator gives a deflection
> >>>>> of .7" for 500lbs of load in the center of a single 8' ramp.
> >>>>>
> >>>> OK, this is great. What does your sagulator say about 1000 lbs load?
> >>> Google "sagulator" and experiment to your heart's content...
> >>>
> >>
> >> I thought that sagulator was a PC program. It is great! I have it
> >> bookmarked and am now experimenting!!!
> >>
> >> Looks like with 2x4x, the deflection of a 1,000 lbs load in the middle
> >> will be about 2 inches, which is too much.
> >>
> >> However, with 2x6s, the deflection will only be 0.36 inches, and 0.7
> >> inches with 2,000 lbs center load.
> >>
> >> So, it seems, that a ramp made to the shape of letter I, could easily
> >> let me deal with 2,000 lbs wheeled loads. (such as a dolly on casters)
> >
> > Well, when you're dealing with that kind of loads, don't forget the
> > supporting ends, joint strength and fasteners, point loading of a caster
> > on the 2x ramp, the downward force of the load back down the ramp
> > running over whatever is in the way, the load limit on a truck tailgate,
> > etc., etc., etc., ...
> >
>
> Well, absolutely. Plus the 2x8 may crack on the middle under such a
> load.
>
> i
For what I expect would be better strength, rigidity and protection from
potential defects in dimensional lumber, try making a glued and screwed
box beam. Something like a top surface layer of three layers of 3/4"
plywood, two or three 2x4 members inside the box, and another layer of
3/4" ply on the bottom. You'd need two sheets of 3/4" ply, six 2x4s and
a lot of glue and screws to make two 1' wide ramps. If you want cleats
at the sides to help keep wheels from running off, apply strips of 1x2
to the top surface along the edges.
Bad ASCII art:
## ##
##################
##################
##################
## ## ##
## ## ##
## ## ##
##################
BTW, the extruded aluminum ramp ends are called "Ramparts" and sold many
places including Depot and Lowe's.
On Sat, 27 Oct 2007 11:34:28 -0500, Ignoramus2057
<[email protected]> wrote:
>I registered it with a 5,000 lbs gross rating, and it did not require
>an inspection in my state.
Nice! IN CT, ANY homebuilt has to be inspected.
I'm sure your work would impress the inspectors. <G>
---------------------------------------------
** http://www.bburke.com/woodworking.html **
---------------------------------------------
Ned Simmons wrote:
>
> On Thu, 25 Oct 2007 12:10:00 -0500, "Pete C." <[email protected]>
> wrote:
>
> >
> >For what I expect would be better strength, rigidity and protection from
> >potential defects in dimensional lumber, try making a glued and screwed
> >box beam. Something like a top surface layer of three layers of 3/4"
> >plywood, two or three 2x4 members inside the box, and another layer of
> >3/4" ply on the bottom.
>
> A box beam of plywood and 2X's would make an excellent ramp, but
> you've got the functions of the plywood and sawn lumber reversed. The
> plywood should be the vertical webs and the 2X's the top and bottom
> plates. The 2X's carry the tension and compression loads; the plywood
> resists the shear between the tension and compression members.
The 2x's could be replaced with ply as well, however using the 2x4s just
makes construction easier. The main point is in putting engineered
lumber i.e. plywood in the positions of stress, eliminating the
potential for an undetected flaw in the dimensional lumber from causing
a catastrophic failure. Indeed, the engineered I joists for building
construction have begun to shift to engineered lumber for the top and
bottom chords of the I joists in place of the earlier dimensional
lumber.
John wrote:
>
> On Thu, 25 Oct 2007 11:45:15 -0400, "Lee Michaels"
> <leemichaels*nadaspam*@comcast.net> wrote:
>
> >
> >"Ignoramus20839" <[email protected]> wrote in message
> >news:[email protected]...
> >>I have steel ramps, but they are very short and suitable for my [low]
> >> trailer only.
> >>
> >> I am considering making ramps from wooden boards. Specifically,
> >> picture a ramp that looks like a letter I in cross section. The wide
> >> part of the I is a 2x8. On the top and bottom of the I, there would be
> >> 2x4s. The "I", of course, would be laid flat for use.
> >>
> >> Here's the ascii graphic:
> >>
> >> . .
> >> |==========|
> >> ~ ~
> >>
> >> The 2x4s would be screwed to the 2x8 with wood screws, and reinforced
> >> with glue.
> >>
> >> My question is, what would be the strength of this ramp if it was,
> >> say, 8 ft long. Specifically, how much load could I place in the
> >> middle for some reasonably low deflection (like 1-2 inches).
> >>
> >> thanks
> >>
> >
> >Two thoughts...
> >
> >Why not just take the 2 X 8's and test them. Put them on a block of some
> >kind on the ground and roll whatever you plan to use them for onto them and
> >observe the deflection. This would be simple and just cost the price of a
> >couple boards.
> >
> >I have seen a number of ramps that have a metal end on them specifically
> >designed for a ramp. I think that would be much more compace and work better
> >than your proposed 2 X 4 ends. I don't know where to purchase them, but
> >they are out there because I have seen them in use many times.
> >
> >
>
> Even your local borg will probably have aluminum "ramp ends" for 2x8
> and 2x10 lumber. They can be secured to a trailer or truck tailgate
> by means of holes in the aluminum pieces and pins that go through
> those holes and into matching holes you drill in the trailer or
> tailgate. The 2x8 version has worked fine for me with 8 foot lumber
> for lawnmowers and snow throwers (heaviest item is about 160lbs). I
> never drilled holes in the tailgate of my 18 year old truck and I
> don't plan to drill holes in the tailgate of the new truck either ;-)
I didn't drill holes in my tailgate either. What I do do though, is use
cargo straps wrapped around each ramp and secured to the bumper to keep
the ramps from slipping off. It wakes you up real fast when a ramp slips
out while you're backing a riding mower out of the truck...
>
> Just FYI, the 1989 Nissan pickup was better built (both assembly and
> design) than the 2008 Tacoma is. The wind noise was lower (after 18
> years) than the new one and the speedometer was more accurate. The
> Tacoma reads 5% high (factory spec is +/- 7%). That 5% error will
> take away 5% of the warranty coverage (3000 miles of a 60000 mile
> warranty). It's all drive-by-wire and the only physical correction is
> a slightly larger tire size (70 series -> 80 series is 5% increase).
> The dealer hasn't done anything yet, except the usual "Im sorry. What
> would make you happy?" and then not following up. The dealer will get
> one more chance at fixing it, then I'll file a "Lemon Law" complaint
> (also covers things that reduce the value of the vehicle) - which they
> must respond to in writing. At least the error will be documented for
> any future warranty claims...
If the dealer hasn't done anything call the regional factory rep. The
calibration is an easy adjustment with a proper scan tool and would take
a competent tech about 5 minutes if they just go by tire measurements
and 10 minutes if they measure the actual rolling radius of the tires.
Ignoramus20839 wrote:
>
> On 2007-10-25, [email protected] <[email protected]> wrote:
> > On Oct 25, 5:39 pm, Ignoramus20839 <ignoramus20...@NOSPAM.
> > 20839.invalid> wrote:
> >
> >> I thought that sagulator was a PC program. It is great! I have it
> >> bookmarked and am now experimenting!!!
> >>
> >> Looks like with 2x4x, the deflection of a 1,000 lbs load in the middle
> >> will be about 2 inches, which is too much.
> >>
> >> However, with 2x6s, the deflection will only be 0.36 inches, and 0.7
> >> inches with 2,000 lbs center load.
> >>
> >> So, it seems, that a ramp made to the shape of letter I, could easily
> >> let me deal with 2,000 lbs wheeled loads. (such as a dolly on casters)
> >>
> >> i
> >
> > While you are playing with the design, think about a couple of blocks
> > you could put between about the middle of the ramp and the ground. If
> > you had a block in the middle of the span, it would be like two 4 foot
> > ramps in series. And I think the capacity would be much higher. So
> > you could use you original design which would be lighter to set in
> > place.
> >
>
> Good point. It is not trivial, though, to add that middle support that
> would be usable with different heights. But it is a very good thought,
> and a solvable problem.
>
> i
Actually, it is pretty trivial, just add an attachment point for basic
RV stabilizer jack stand. Something like this:
http://www.campersworld.com/product-view.php?product_id=3332:4204
Mike Marlow wrote:
>
> "Pete C." <[email protected]> wrote in message
> news:[email protected]...
>
> >
> > For what I expect would be better strength, rigidity and protection from
> > potential defects in dimensional lumber, try making a glued and screwed
> > box beam. Something like a top surface layer of three layers of 3/4"
> > plywood,
>
> Holy Cow!!! Talk about over engineered! Three layers of 3/4" ply?
> Expensive and heavy.
<$100 to build the pair of ramps. Would you want to screw around with
borderline engineered ramps when trying to move a couple thousand
pounds?
>
> > two or three 2x4 members inside the box, and another layer of
> > 3/4" ply on the bottom. You'd need two sheets of 3/4" ply, six 2x4s and
> > a lot of glue and screws to make two 1' wide ramps. If you want cleats
> > at the sides to help keep wheels from running off, apply strips of 1x2
> > to the top surface along the edges.
>
> And get a second truck to follow along and carry the ramps. But - no doubt
> they will be strong.
Probably about 60# each. Not that heavy really.
"Ignoramus7291" <[email protected]> wrote in message
news:[email protected]...
> On 2007-10-26, B A R R Y <[email protected]> wrote:
>> Mike Marlow wrote:
>>>
>>> Who's going to be
>>> building ramps to load a couple thousand pound object into the back of a
>>> pickup?
>>
>> I'd like to see the pickup with a couple thousand pounds in the back.
>>
>> May the OP should just give up and hire a roll-back. <G>
>>
>
> I have a trailer that can carry a lot more than 2,000 lbs. I made it
> myself, kind of.
>
> http://igor.chudov.com/projects/Homemade-Trailer-With-M105A2-Bed/
>
> It can carry about 4k lbs.
>
Is that a real rating? Seems like that would be kinda high for a single
axle trailer like that.
--
-Mike-
[email protected]
"Ignoramus20839" <[email protected]> wrote in message
news:[email protected]...
>
> So, it seems, that a ramp made to the shape of letter I, could easily
> let me deal with 2,000 lbs wheeled loads. (such as a dolly on casters)
>
Why the "I" on the ramp? Especially at the ground end, it serves no purpose
that I can see and only makes it harder to get things started up the ramp.
--
-Mike-
[email protected]
"Pete C." <[email protected]> wrote in message
news:[email protected]...
>
> For what I expect would be better strength, rigidity and protection from
> potential defects in dimensional lumber, try making a glued and screwed
> box beam. Something like a top surface layer of three layers of 3/4"
> plywood,
Holy Cow!!! Talk about over engineered! Three layers of 3/4" ply?
Expensive and heavy.
> two or three 2x4 members inside the box, and another layer of
> 3/4" ply on the bottom. You'd need two sheets of 3/4" ply, six 2x4s and
> a lot of glue and screws to make two 1' wide ramps. If you want cleats
> at the sides to help keep wheels from running off, apply strips of 1x2
> to the top surface along the edges.
And get a second truck to follow along and carry the ramps. But - no doubt
they will be strong.
--
-Mike-
[email protected]
On Thu, 25 Oct 2007 12:50:46 -0500, "Pete C." <[email protected]>
wrote:
>Ned Simmons wrote:
>>
>> On Thu, 25 Oct 2007 12:10:00 -0500, "Pete C." <[email protected]>
>> wrote:
>>
>> >
>> >For what I expect would be better strength, rigidity and protection from
>> >potential defects in dimensional lumber, try making a glued and screwed
>> >box beam. Something like a top surface layer of three layers of 3/4"
>> >plywood, two or three 2x4 members inside the box, and another layer of
>> >3/4" ply on the bottom.
>>
>> A box beam of plywood and 2X's would make an excellent ramp, but
>> you've got the functions of the plywood and sawn lumber reversed. The
>> plywood should be the vertical webs and the 2X's the top and bottom
>> plates. The 2X's carry the tension and compression loads; the plywood
>> resists the shear between the tension and compression members.
>
>The 2x's could be replaced with ply as well, however using the 2x4s just
>makes construction easier.
No question about that.
>The main point is in putting engineered
>lumber i.e. plywood in the positions of stress, eliminating the
>potential for an undetected flaw in the dimensional lumber from causing
>a catastrophic failure.
But there is stress in both the webs and flanges. With a little care
in selecting the 2Xs you're unlikely to have a problem using them in
tension or compression for the bottom and top plates. Any hidden
defects, or overloading, are much more likely to cause a failure along
the grain if they're subject to shear. The criss-cross grain of the
plywood makes it the better choice for carrying the shear in the webs.
--
Ned Simmons
"Pete C." <[email protected]> wrote in message
news:[email protected]...
> Mike Marlow wrote:
>>
>> "Pete C." <[email protected]> wrote in message
>> news:[email protected]...
>>
>> >
>> > For what I expect would be better strength, rigidity and protection
>> > from
>> > potential defects in dimensional lumber, try making a glued and screwed
>> > box beam. Something like a top surface layer of three layers of 3/4"
>> > plywood,
>>
>> Holy Cow!!! Talk about over engineered! Three layers of 3/4" ply?
>> Expensive and heavy.
>
> <$100 to build the pair of ramps. Would you want to screw around with
> borderline engineered ramps when trying to move a couple thousand
> pounds?
How did this get to be a couple thousand pound project? Wasn't the OP
talking about such things as mowers and snowblowers? Who's going to be
building ramps to load a couple thousand pound object into the back of a
pickup?
>
>>
>> > two or three 2x4 members inside the box, and another layer of
>> > 3/4" ply on the bottom. You'd need two sheets of 3/4" ply, six 2x4s and
>> > a lot of glue and screws to make two 1' wide ramps. If you want cleats
>> > at the sides to help keep wheels from running off, apply strips of 1x2
>> > to the top surface along the edges.
>>
>> And get a second truck to follow along and carry the ramps. But - no
>> doubt
>> they will be strong.
>
> Probably about 60# each. Not that heavy really.
Very heavy compared to the alternatives.
--
-Mike-
[email protected]
On 2007-10-25, Pete C. <[email protected]> wrote:
> Ignoramus20839 wrote:
>>
>> sOn 2007-10-25, dpb <[email protected]> wrote:
>> > Ignoramus20839 wrote:
>> >> On 2007-10-25, dpb <[email protected]> wrote:
>> >>> Ignoramus20839 wrote:
>> >>>> On 2007-10-25, Chris Friesen <[email protected]> wrote:
>> >>>>> Ignoramus20839 wrote:
>> >>>>>
>> >>>>>> My question is, what would be the strength of this ramp if it was,
>> >>>>>> say, 8 ft long. Specifically, how much load could I place in the
>> >>>>>> middle for some reasonably low deflection (like 1-2 inches).
>> >>>>> Using spruce pine and ignoring the 2x8, the sagulator gives a deflection
>> >>>>> of .7" for 500lbs of load in the center of a single 8' ramp.
>> >>>>>
>> >>>> OK, this is great. What does your sagulator say about 1000 lbs load?
>> >>> Google "sagulator" and experiment to your heart's content...
>> >>>
>> >>
>> >> I thought that sagulator was a PC program. It is great! I have it
>> >> bookmarked and am now experimenting!!!
>> >>
>> >> Looks like with 2x4x, the deflection of a 1,000 lbs load in the middle
>> >> will be about 2 inches, which is too much.
>> >>
>> >> However, with 2x6s, the deflection will only be 0.36 inches, and 0.7
>> >> inches with 2,000 lbs center load.
>> >>
>> >> So, it seems, that a ramp made to the shape of letter I, could easily
>> >> let me deal with 2,000 lbs wheeled loads. (such as a dolly on casters)
>> >
>> > Well, when you're dealing with that kind of loads, don't forget the
>> > supporting ends, joint strength and fasteners, point loading of a caster
>> > on the 2x ramp, the downward force of the load back down the ramp
>> > running over whatever is in the way, the load limit on a truck tailgate,
>> > etc., etc., etc., ...
>> >
>>
>> Well, absolutely. Plus the 2x8 may crack on the middle under such a
>> load.
>>
>> i
>
> For what I expect would be better strength, rigidity and protection from
> potential defects in dimensional lumber, try making a glued and screwed
> box beam. Something like a top surface layer of three layers of 3/4"
> plywood, two or three 2x4 members inside the box, and another layer of
> 3/4" ply on the bottom. You'd need two sheets of 3/4" ply, six 2x4s and
> a lot of glue and screws to make two 1' wide ramps. If you want cleats
> at the sides to help keep wheels from running off, apply strips of 1x2
> to the top surface along the edges.
>
> Bad ASCII art:
>
> ## ##
> ##################
> ##################
> ##################
> ## ## ##
> ## ## ##
> ## ## ##
> ##################
>
> BTW, the extruded aluminum ramp ends are called "Ramparts" and sold many
> places including Depot and Lowe's.
I think that it is going to be kind of big. But I will think about
it. By the way, I heeded your advice and bought the HF load balancer a
year ago. I will check those ramparts, I am sure that I will need
them. But maybe I will make them.
i
On 2007-10-26, Mike Marlow <[email protected]> wrote:
>
> "Ignoramus7291" <[email protected]> wrote in message
> news:[email protected]...
>> On 2007-10-26, B A R R Y <[email protected]> wrote:
>>> Mike Marlow wrote:
>>>>
>>>> Who's going to be
>>>> building ramps to load a couple thousand pound object into the back of a
>>>> pickup?
>>>
>>> I'd like to see the pickup with a couple thousand pounds in the back.
>>>
>>> May the OP should just give up and hire a roll-back. <G>
>>>
>>
>> I have a trailer that can carry a lot more than 2,000 lbs. I made it
>> myself, kind of.
>>
>> http://igor.chudov.com/projects/Homemade-Trailer-With-M105A2-Bed/
>>
>> It can carry about 4k lbs.
>>
>
> Is that a real rating? Seems like that would be kinda high for a single
> axle trailer like that.
>
The axle is 6,000 lbs rated. I bought it new. The entire trailer
weighs less than 2,000 lbs. My estimate is about 1,700 lbs.
i
"Ignoramus20839" <[email protected]> wrote in message
news:[email protected]...
>I have steel ramps, but they are very short and suitable for my [low]
> trailer only.
>
> I am considering making ramps from wooden boards. Specifically,
> picture a ramp that looks like a letter I in cross section. The wide
> part of the I is a 2x8. On the top and bottom of the I, there would be
> 2x4s. The "I", of course, would be laid flat for use.
>
> Here's the ascii graphic:
>
> . .
> |==========|
> ~ ~
>
> The 2x4s would be screwed to the 2x8 with wood screws, and reinforced
> with glue.
>
> My question is, what would be the strength of this ramp if it was,
> say, 8 ft long. Specifically, how much load could I place in the
> middle for some reasonably low deflection (like 1-2 inches).
>
> thanks
>
Two thoughts...
Why not just take the 2 X 8's and test them. Put them on a block of some
kind on the ground and roll whatever you plan to use them for onto them and
observe the deflection. This would be simple and just cost the price of a
couple boards.
I have seen a number of ramps that have a metal end on them specifically
designed for a ramp. I think that would be much more compace and work better
than your proposed 2 X 4 ends. I don't know where to purchase them, but
they are out there because I have seen them in use many times.
"Ignoramus7291" <[email protected]> wrote in message
news:[email protected]...
> On 2007-10-26, Ignoramus7291 <[email protected]> wrote:
>> I love the camo job, yes, and here's my dilemma. I feel like I need to
>> sand and paint over some spots, but I do not know how to prevent the
>> pattern.
>
> I mean, how to keep the pattern, I do not know what I was thinking.
>
That information has to be around someplace. i have seen good cammo paint
jobs done with spray paint (in a can).
On 2007-10-26, B A R R Y <[email protected]> wrote:
> Mike Marlow wrote:
>>
>> Who's going to be
>> building ramps to load a couple thousand pound object into the back of a
>> pickup?
>
> I'd like to see the pickup with a couple thousand pounds in the back.
>
> May the OP should just give up and hire a roll-back. <G>
>
I have a trailer that can carry a lot more than 2,000 lbs. I made it
myself, kind of.
http://igor.chudov.com/projects/Homemade-Trailer-With-M105A2-Bed/
It can carry about 4k lbs.
i
On 2007-10-26, B A R R Y <[email protected]> wrote:
> Ignoramus7291 wrote:
>
>>
>> I have a trailer that can carry a lot more than 2,000 lbs. I made it
>> myself, kind of.
>
> Nice!
Barry, thank you!
Somewhat wood related (wood vs. metal), I really like the fact that
its bottom (deck) is made from steel, not wood. Makes a lot of things
a lot easier. (like dragging stuff)
i
On 2007-10-25, Chris Friesen <[email protected]> wrote:
> Ignoramus20839 wrote:
>
>> My question is, what would be the strength of this ramp if it was,
>> say, 8 ft long. Specifically, how much load could I place in the
>> middle for some reasonably low deflection (like 1-2 inches).
>
> Using spruce pine and ignoring the 2x8, the sagulator gives a deflection
> of .7" for 500lbs of load in the center of a single 8' ramp.
>
OK, this is great. What does your sagulator say about 1000 lbs load?
also, what would it say if I replaced 2x4s with 2x6s?
I appreciate your help . Thanks a lot.
i
"Lee Michaels" <leemichaels*nadaspam*@comcast.net> wrote in message
news:[email protected]...
>
> Why not just take the 2 X 8's and test them. Put them on a block of some
> kind on the ground and roll whatever you plan to use them for onto them
> and observe the deflection. This would be simple and just cost the price
> of a couple boards.
>
> I have seen a number of ramps that have a metal end on them specifically
> designed for a ramp. I think that would be much more compace and work
> better than your proposed 2 X 4 ends. I don't know where to purchase
> them, but they are out there because I have seen them in use many times.
>
>
>
Home Depot sells the ramp ends pretty cheap. They're in the Outdoor Garden
department.
--
-Mike-
[email protected]
Ignoramus20839 wrote:
> I have steel ramps, but they are very short and suitable for my [low]
> trailer only.
>
> I am considering making ramps from wooden boards. Specifically,
> picture a ramp that looks like a letter I in cross section. The wide
> part of the I is a 2x8. On the top and bottom of the I, there would be
> 2x4s. The "I", of course, would be laid flat for use.
>
> Here's the ascii graphic:
>
> . .
> |==========|
> ~ ~
>
> The 2x4s would be screwed to the 2x8 with wood screws, and reinforced
> with glue.
>
> My question is, what would be the strength of this ramp if it was,
> say, 8 ft long. Specifically, how much load could I place in the
> middle for some reasonably low deflection (like 1-2 inches).
It is simply a 3x3-1/2 beam for estimating purposes. You can forget the
2x8 in the horizontal as it is conservative to do so.
I don't have a link ottomh, but a google will find any number of beam
deflection engines.
Use SYP or fir for higher modulus and, of course, be sure it is
defect-free timber.
Depending on length and weight desired, going w/ 2x6 tapered some for
the ends might be more suitable at the expense of a little more
weight/heft/bulk...
--
Ignoramus20839 wrote:
> On 2007-10-25, Chris Friesen <[email protected]> wrote:
>> Ignoramus20839 wrote:
>>
>>> My question is, what would be the strength of this ramp if it was,
>>> say, 8 ft long. Specifically, how much load could I place in the
>>> middle for some reasonably low deflection (like 1-2 inches).
>> Using spruce pine and ignoring the 2x8, the sagulator gives a deflection
>> of .7" for 500lbs of load in the center of a single 8' ramp.
>>
>
> OK, this is great. What does your sagulator say about 1000 lbs load?
Google "sagulator" and experiment to your heart's content...
--
Ignoramus20839 wrote:
> On 2007-10-25, dpb <[email protected]> wrote:
>> Ignoramus20839 wrote:
>>> On 2007-10-25, Chris Friesen <[email protected]> wrote:
>>>> Ignoramus20839 wrote:
>>>>
>>>>> My question is, what would be the strength of this ramp if it was,
>>>>> say, 8 ft long. Specifically, how much load could I place in the
>>>>> middle for some reasonably low deflection (like 1-2 inches).
>>>> Using spruce pine and ignoring the 2x8, the sagulator gives a deflection
>>>> of .7" for 500lbs of load in the center of a single 8' ramp.
>>>>
>>> OK, this is great. What does your sagulator say about 1000 lbs load?
>> Google "sagulator" and experiment to your heart's content...
>>
>
> I thought that sagulator was a PC program. It is great! I have it
> bookmarked and am now experimenting!!!
>
> Looks like with 2x4x, the deflection of a 1,000 lbs load in the middle
> will be about 2 inches, which is too much.
>
> However, with 2x6s, the deflection will only be 0.36 inches, and 0.7
> inches with 2,000 lbs center load.
>
> So, it seems, that a ramp made to the shape of letter I, could easily
> let me deal with 2,000 lbs wheeled loads. (such as a dolly on casters)
Well, when you're dealing with that kind of loads, don't forget the
supporting ends, joint strength and fasteners, point loading of a caster
on the 2x ramp, the downward force of the load back down the ramp
running over whatever is in the way, the load limit on a truck tailgate,
etc., etc., etc., ...
--
On Fri, 26 Oct 2007 09:45:11 -0500, Ignoramus7291
<[email protected]> wrote:
>On 2007-10-26, Ignoramus7291 <[email protected]> wrote:
>> I love the camo job, yes, and here's my dilemma. I feel like I need to
>> sand and paint over some spots, but I do not know how to prevent the
>> pattern.
>
>I mean, how to keep the pattern, I do not know what I was thinking.
Durrr! Take lots of pictures, so you can duplicate it! ;-P
Locate spray cans of the flat camo paint colors you need or have
them mixed if you want to use a touch-up spray gun. Some mixed paints
with flattening additives need to be shot 'fresh' (within a few months
of mixing) or they revert to semi-gloss.
Fix the rusty.dented spots. Prime and spray base coat.
If the spots have fuzzy edges, you can freehand the camo splotches.
Practice each color on a piece of cardboard to make sure the gun is
primed and shooting a solid pattern before you go for the trailer.
If you want defined edges, use plain old masking tape to outline the
paint areas and then mask off the surrounding area - depending on the
paint chemistry the 3M Blue (long mask) or Green (tough surface) tape.
They have tapes with specialized adhesives to work with lacquers and
certain other aggressive solvents. Read the label.
--<< Bruce >>--
On Sat, 27 Oct 2007 07:49:05 -0400, B A R R Y <[email protected]>
wrote:
>On Fri, 26 Oct 2007 21:04:00 -0700, "Roger Shoaf"
><[email protected]> wrote:
>
>>Any one of those specs exceeded and the Highway Patrol can side line the
>>trailer until the load can be made legal and weight tickets like this are
>>priced by the pound.
>
>In my state of CT, you register a trailer for a stated gross weight,
>subject to inspection. All homebuilt trailers are required to be
>inspected to get initial and transfer registrations. Are there
>states that just hand a plate to a homebuilt trailer without
>inspecting it?
Here in Maine all they want to know about small homebuilt trailers is
the color and what you paid for it <g>. But I assume you can be cited
for unsafe operation or some other catchall if you're doing something
stupid.
--
Ned Simmons
[email protected] wrote:
> On Oct 25, 3:10 pm, "[email protected]" <[email protected]> wrote:
>> On Oct 25, 7:22 pm, Ignoramus20839 >
>>
>>> Good point. It is not trivial, though, to add that middle support
>>> that would be usable with different heights. But it is a very good
>>> thought, and a solvable problem.
>>
>>> i
>>
>> You don't have to have it height adjustable. Just a reasonable
>> size
>> so it will fit under the ramp. If the ramp is being used for a low
>> thing, the support may be close to the high end, and the
>> unsupported
>> length a two foot span and a six foot span. If it is being used on
>> a
>> very high thing, the support may be close to the ground end, and
>> again you have a two foot and six foot span. But when you play
>> with
>> the program you will see a six foot span is much better than an
>> eight
>> foot span.
>>
>> Of course cutting in to two four foot spans is even better, and
>> those
>> aluminum support jacks look like a nice solution.
>>
>> Dan
>
> Using deflection as a criterion for beam design is not to be
> condoned.
>
> The beam MUST be designed with an allowable BENDING stress in the
> top
> and bottom flange of the beam.
>
> Once this stress is at an acceptable level can the design be checked
> for deflection and, if too large, the beam be made stronger TO
> REDUCE
> THE DEFLECTION.
>
> Starting with deflection one has no idea what the bending stress is
> and whether it has exceeded the allowable limit.
>
> Since I generally do not design in wood..... if someone will supply
> the info on type and grade of lumber, and allowable bending stress
> (from a building code, perhaps) I would let you know the load
> capacity.
The building codes for residential wooden structures do not in general
specify allowable bending stress, they specify allowable deflection.
--
--
--John
to email, dial "usenet" and validate
(was jclarke at eye bee em dot net)
Joseph Gwinn wrote:
> In article <[email protected]>,
> [email protected] wrote:
>
>> On Oct 25, 3:10 pm, "[email protected]" <[email protected]> wrote:
>>> On Oct 25, 7:22 pm, Ignoramus20839 >
>>>
>>>> Good point. It is not trivial, though, to add that middle support
>>>> that would be usable with different heights. But it is a very
>>>> good
>>>> thought, and a solvable problem.
>>>
>>>> i
>>>
>>> You don't have to have it height adjustable. Just a reasonable
>>> size
>>> so it will fit under the ramp. If the ramp is being used for a
>>> low
>>> thing, the support may be close to the high end, and the
>>> unsupported
>>> length a two foot span and a six foot span. If it is being used
>>> on
>>> a very high thing, the support may be close to the ground end,
>>> and
>>> again you have a two foot and six foot span. But when you play
>>> with
>>> the program you will see a six foot span is much better than an
>>> eight foot span.
>>>
>>> Of course cutting in to two four foot spans is even better, and
>>> those aluminum support jacks look like a nice solution.
>>>
>>> Dan
>>
>> Using deflection as a criterion for beam design is not to be
>> condoned.
>>
>> The beam MUST be designed with an allowable BENDING stress in the
>> top
>> and bottom flange of the beam.
>>
>> Once this stress is at an acceptable level can the design be
>> checked
>> for deflection and, if too large, the beam be made stronger TO
>> REDUCE
>> THE DEFLECTION.
>>
>> Starting with deflection one has no idea what the bending stress is
>> and whether it has exceeded the allowable limit.
>>
>> Since I generally do not design in wood..... if someone will supply
>> the info on type and grade of lumber, and allowable bending stress
>> (from a building code, perhaps) I would let you know the load
>> capacity.
>
> I think that Machinery's Handbook has strength and modulus data on
> wood.
http://www.fpl.fs.fed.us/documnts/fplgtr/fplgtr113/fplgtr113.htm
> One thing to consider is tipping due to an offcenter load, if the
> road
> surface is too soft and the ramp too narrow.
>
> Joe Gwinn
--
--
--John
to email, dial "usenet" and validate
(was jclarke at eye bee em dot net)
On 2007-10-26, Ignoramus7291 <[email protected]> wrote:
> I love the camo job, yes, and here's my dilemma. I feel like I need to
> sand and paint over some spots, but I do not know how to prevent the
> pattern.
I mean, how to keep the pattern, I do not know what I was thinking.
i
On 2007-10-26, Lee Michaels <leemichaels*nadaspam*@comcast.net> wrote:
>
> "Ignoramus7291" wrote
>>
>> I have a trailer that can carry a lot more than 2,000 lbs. I made it
>> myself, kind of.
>>
>> http://igor.chudov.com/projects/Homemade-Trailer-With-M105A2-Bed/
>>
>> It can carry about 4k lbs.
>>
>
> After viewing your very impressive trailer build, I have two very irreverant
> thoughts.
>
> The first is a mental picture of those crummy trailer kits sold at
> the borg and Harbor Freight.
I bought one once. Sold it to my friend promptly. Could not stand the
sight of it.
> What you built is twenty times heavier, a hundred times more sturdy and
> million times more classy that those cheap kits.
It is more like 10 times heavier. But yes. This is "the real thing".
> The second thought is that cammo paint job looks really good on the trailer.
> When are you going to paint the truck to match the trailer?
I love the camo job, yes, and here's my dilemma. I feel like I need to
sand and paint over some spots, but I do not know how to prevent the
pattern.
This trailer actually gets compliments from completely random people
on the streets.
Did you see the pictures of bullet holes on this trailer? (real bullet
holes, not fake stickers)
Making it was fun. It was my winter project. It actually took
relatively little time due to me wanting to get it out of the garage
so as to not tp upset my wife too much. But it was as lot of work.
i
On 2007-10-25, dpb <[email protected]> wrote:
> Ignoramus20839 wrote:
>> On 2007-10-25, Chris Friesen <[email protected]> wrote:
>>> Ignoramus20839 wrote:
>>>
>>>> My question is, what would be the strength of this ramp if it was,
>>>> say, 8 ft long. Specifically, how much load could I place in the
>>>> middle for some reasonably low deflection (like 1-2 inches).
>>> Using spruce pine and ignoring the 2x8, the sagulator gives a deflection
>>> of .7" for 500lbs of load in the center of a single 8' ramp.
>>>
>>
>> OK, this is great. What does your sagulator say about 1000 lbs load?
>
> Google "sagulator" and experiment to your heart's content...
>
I thought that sagulator was a PC program. It is great! I have it
bookmarked and am now experimenting!!!
Looks like with 2x4x, the deflection of a 1,000 lbs load in the middle
will be about 2 inches, which is too much.
However, with 2x6s, the deflection will only be 0.36 inches, and 0.7
inches with 2,000 lbs center load.
So, it seems, that a ramp made to the shape of letter I, could easily
let me deal with 2,000 lbs wheeled loads. (such as a dolly on casters)
i
On Fri, 26 Oct 2007 21:04:00 -0700, "Roger Shoaf"
<[email protected]> wrote:
>Any one of those specs exceeded and the Highway Patrol can side line the
>trailer until the load can be made legal and weight tickets like this are
>priced by the pound.
In my state of CT, you register a trailer for a stated gross weight,
subject to inspection. All homebuilt trailers are required to be
inspected to get initial and transfer registrations. Are there
states that just hand a plate to a homebuilt trailer without
inspecting it? I would imagine Ig had to have his fine workmanship
inspected at registration.
If you're under the card GVW weights for the trailer and tow vehicle,
you're good to go, no negotiating required.
Many recent pickups are rated for at least a 6000 pound tow. Even my
"midsize" '05 Tacoma can legally tow 6500. Unless you're driving
like a bad episode of "CHIPS", I doubt most cops would bat an eyelash
at Ig's trailer behind a full-size pickup.
---------------------------------------------
** http://www.bburke.com/woodworking.html **
---------------------------------------------
On Thu, 25 Oct 2007 11:45:15 -0400, "Lee Michaels"
<leemichaels*nadaspam*@comcast.net> wrote:
>
>"Ignoramus20839" <[email protected]> wrote in message
>news:[email protected]...
>>I have steel ramps, but they are very short and suitable for my [low]
>> trailer only.
>>
>> I am considering making ramps from wooden boards. Specifically,
>> picture a ramp that looks like a letter I in cross section. The wide
>> part of the I is a 2x8. On the top and bottom of the I, there would be
>> 2x4s. The "I", of course, would be laid flat for use.
>>
>> Here's the ascii graphic:
>>
>> . .
>> |==========|
>> ~ ~
>>
>> The 2x4s would be screwed to the 2x8 with wood screws, and reinforced
>> with glue.
>>
>> My question is, what would be the strength of this ramp if it was,
>> say, 8 ft long. Specifically, how much load could I place in the
>> middle for some reasonably low deflection (like 1-2 inches).
>>
>> thanks
>>
>
>Two thoughts...
>
>Why not just take the 2 X 8's and test them. Put them on a block of some
>kind on the ground and roll whatever you plan to use them for onto them and
>observe the deflection. This would be simple and just cost the price of a
>couple boards.
>
>I have seen a number of ramps that have a metal end on them specifically
>designed for a ramp. I think that would be much more compace and work better
>than your proposed 2 X 4 ends. I don't know where to purchase them, but
>they are out there because I have seen them in use many times.
>
>
Even your local borg will probably have aluminum "ramp ends" for 2x8
and 2x10 lumber. They can be secured to a trailer or truck tailgate
by means of holes in the aluminum pieces and pins that go through
those holes and into matching holes you drill in the trailer or
tailgate. The 2x8 version has worked fine for me with 8 foot lumber
for lawnmowers and snow throwers (heaviest item is about 160lbs). I
never drilled holes in the tailgate of my 18 year old truck and I
don't plan to drill holes in the tailgate of the new truck either ;-)
Just FYI, the 1989 Nissan pickup was better built (both assembly and
design) than the 2008 Tacoma is. The wind noise was lower (after 18
years) than the new one and the speedometer was more accurate. The
Tacoma reads 5% high (factory spec is +/- 7%). That 5% error will
take away 5% of the warranty coverage (3000 miles of a 60000 mile
warranty). It's all drive-by-wire and the only physical correction is
a slightly larger tire size (70 series -> 80 series is 5% increase).
The dealer hasn't done anything yet, except the usual "Im sorry. What
would make you happy?" and then not following up. The dealer will get
one more chance at fixing it, then I'll file a "Lemon Law" complaint
(also covers things that reduce the value of the vehicle) - which they
must respond to in writing. At least the error will be documented for
any future warranty claims...
John
In article <[email protected]>,
[email protected] wrote:
> On Oct 25, 3:10 pm, "[email protected]" <[email protected]> wrote:
> > On Oct 25, 7:22 pm, Ignoramus20839 >
> >
> > > Good point. It is not trivial, though, to add that middle support that
> > > would be usable with different heights. But it is a very good thought,
> > > and a solvable problem.
> >
> > > i
> >
> > You don't have to have it height adjustable. Just a reasonable size
> > so it will fit under the ramp. If the ramp is being used for a low
> > thing, the support may be close to the high end, and the unsupported
> > length a two foot span and a six foot span. If it is being used on a
> > very high thing, the support may be close to the ground end, and
> > again you have a two foot and six foot span. But when you play with
> > the program you will see a six foot span is much better than an eight
> > foot span.
> >
> > Of course cutting in to two four foot spans is even better, and those
> > aluminum support jacks look like a nice solution.
> >
> > Dan
>
> Using deflection as a criterion for beam design is not to be condoned.
>
> The beam MUST be designed with an allowable BENDING stress in the top
> and bottom flange of the beam.
>
> Once this stress is at an acceptable level can the design be checked
> for deflection and, if too large, the beam be made stronger TO REDUCE
> THE DEFLECTION.
>
> Starting with deflection one has no idea what the bending stress is
> and whether it has exceeded the allowable limit.
>
> Since I generally do not design in wood..... if someone will supply
> the info on type and grade of lumber, and allowable bending stress
> (from a building code, perhaps) I would let you know the load
> capacity.
I think that Machinery's Handbook has strength and modulus data on wood.
One thing to consider is tipping due to an offcenter load, if the road
surface is too soft and the ramp too narrow.
Joe Gwinn
On 2007-10-27, Roger Shoaf <[email protected]> wrote:
>
> "Ignoramus7291" <[email protected]> wrote in message
> news:[email protected]...
>> The axle is 6,000 lbs rated. I bought it new. The entire trailer
>> weighs less than 2,000 lbs. My estimate is about 1,700 lbs.
>>
>> i
>
> The axel rating is only part of the equation, you also can't exceed the tire
> rating nor the rating of the vehicle pulling the trailer.
Tires came with the axle. The truck is rated for something like 9k
lbs. The hitch, I think 10k lbs.
> Any one of those specs exceeded and the Highway Patrol can side line the
> trailer until the load can be made legal and weight tickets like this are
> priced by the pound.
>
Agreed.
i
On Thu, 25 Oct 2007 11:48:26 -0500, Ignoramus20839
<[email protected]> wrote:
<snip>
>> Well, when you're dealing with that kind of loads, don't forget the
>> supporting ends, joint strength and fasteners, point loading of a caster
>Well, absolutely. Plus the 2x8 may crack on the middle under such a
>load.
>
>i
Just as a reference, my father made some ramps of 3"x12"x~10' rough
sawn live oak he used for over 30 years to load levee rollers on the
bobtail IH. The levee rollers were concrete spools with heavy angle
frames that weighed about 4800 lbs. We'd put three on the truck and
deliver them around to implement dealers, which is why I had a
commercial license at 16. Dad had mounted a hydraulic winch in the
bed, and we'd tilt the dump bed about 5 deg. up to load and unload.
Those old loading ramps never broke, although they did develop a
raised ridge over time down the middle. I guess something to do with
the way they were sawn.
Every time I took a load through the old Baytown tunnel, I'd have to
stop for an inspection. The chain boom handles had to be safety
wired, 2"x4" cleats nailed behind the rollers, etc. I guess they
didn't want to see three rollers unload down the tunnel as I exited.
The ramps were also a bear to handle, being pretty damn heavy. The
attachment to the bobtail (single rear axle truck) was just a small
angle bolted to the ramp set in a groove formed by a piece of bar
welded to the back of the bed.
On 2007-10-25, [email protected] <[email protected]> wrote:
> On Oct 25, 5:39 pm, Ignoramus20839 <ignoramus20...@NOSPAM.
> 20839.invalid> wrote:
>
>> I thought that sagulator was a PC program. It is great! I have it
>> bookmarked and am now experimenting!!!
>>
>> Looks like with 2x4x, the deflection of a 1,000 lbs load in the middle
>> will be about 2 inches, which is too much.
>>
>> However, with 2x6s, the deflection will only be 0.36 inches, and 0.7
>> inches with 2,000 lbs center load.
>>
>> So, it seems, that a ramp made to the shape of letter I, could easily
>> let me deal with 2,000 lbs wheeled loads. (such as a dolly on casters)
>>
>> i
>
> While you are playing with the design, think about a couple of blocks
> you could put between about the middle of the ramp and the ground. If
> you had a block in the middle of the span, it would be like two 4 foot
> ramps in series. And I think the capacity would be much higher. So
> you could use you original design which would be lighter to set in
> place.
>
Good point. It is not trivial, though, to add that middle support that
would be usable with different heights. But it is a very good thought,
and a solvable problem.
i