I want to make a part using 1 1/4 square tubing,
or about this size.(Steel)
And I would like to have another piece of square
tubing that will slide inside this tubing.
I've found at my local metal place that the
smaller sizes are too loose.
I was going to put in some shims to make it work.
But can you buy square tubing 'somewhere' that
is made to fit inside for applications like I need?
So, can you get this tubing and what is it called?
(The part won't be in motion.)
I went to the website and it says that the wall is .105 and the tubing
is sized .250 larger than the previous size. That would mean there is
.040 slop. Have you used the stuff much? Does it seem as sloppy as
Princess Auto up in Canada has telescopic square tube in 1-1/4".
The pieces are 4 feet long and cost $16CDN each. They also sell
1" stuff that just fits inside, $13CDN per 4 foot piece. Spendy,
but then it's a specialty item. Princess Auto used to be real
friendly about shipping to the US. Their Web site is now much
more obnoxious - they require you to "register" before you can
browse their catalog docs.
I use it quite often. It does wobble some, depending on the ratio of
inserted length vs total length. Depends on what you have in mind, I guess.
There are angle and tee brackets to make it easier to assemble frames,etc.
One way I've long thought about for doing telescoping square steel
tubing is to use tubing sizes that are separated by 1/2" and then
weld in 1/4" shims at the top of one end and file to fit smoothly
and then weld in 1/4" shims at the back end of the inner tube and
file to fit smoothly, and then the inner tube should be a nice
fit in the outer tube and cannot come out the end either. That's
similar to the way the boom on my old boom truck was made. - GWE
Actually, you can do this with most any reasonable combination of sizes
but mostly .083 wall tubes 1/4" apart and .120 and .187 wall 1/2" apart.
And it has the advantage that you can file a notch in the shim plates to
accomodate the weld flash. After that all you have to deal with is the
extra rounded corners on the larger square tube sizes and the hollowed
out sices that come with some cheaper suppliers of tube.
Grant Erw> One way I've long thought about for doing telescoping square steel
> tubing is to use tubing sizes that are separated by 1/2" and then
> weld in 1/4" shims at the top of one end and file to fit smoothly
> and then weld in 1/4" shims at the back end of the inner tube and
> file to fit smoothly, and then the inner tube should be a nice
> fit in the outer tube and cannot come out the end either. That's
> similar to the way the boom on my old boom truck was made. - GWE
Use UHMW instead of Teflon. Teflon cold flows far more than UHMW. Our
catamafan had a Teflon washer under the mast foot (pivoting mast) that
would squeeze out a few times each season. A few years ago I replaced
it with a UHMW washer and it remains serviceable to this day.
Teflon's big advantage is at high temperatures.
Try telspar by unistrut. The square sign post stuff that lots of
cities use fer traffic signs. With or without holes. You used to be
able to pick up the broke stuff cheap. Shit dat peoples runt over.