Can anyone point me to a table with the standard radius for corners for
different steel forms?
I want to place 2x4 tubing inside either a 3" or 4" angle iron and don't
know if the inside radius of the angle iron will allow the 2x4" tubing to
set 'flat' on both legs of the angle iron.


TT



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On 27 Nov 2008 01:18:32 GMT, (thito01)
wrote:

Can anyone point me to a table with the standard radius for corners for
different steel forms?
I want to place 2x4 tubing inside either a 3" or 4" angle iron and don't
know if the inside radius of the angle iron will allow the 2x4" tubing to
set 'flat' on both legs of the angle iron.


TT

Hey TT,

Varies by producer, and not only that, on "most" standard angle, the
"legs" are tapered and not of constant thickness, so it won't form a
90 degree "inside" corner.

Take care.

Brian Lawson,
Bothwell, Ontario.

On Nov 26, 8:18*pm, (thito01) wrote:
Can anyone point me to a table with the standard radius for corners for
different steel forms?
I want to place 2x4 tubing inside either a 3" or 4" angle iron and don't
know if the inside radius of the angle iron will allow the 2x4" tubing to
set 'flat' on both legs of the angle iron.

I've drawn the shapes in my scrap pile into my CAD library, and found
that different lots of the same nominal size varied in the details
such as inside radius and the parallelism of channel flanges. The
surface finish of angle was poor enough that even the correct radius
didn't fit tightly without some cleanup with an angle grinder. The
flanges of some of the angle are slightly tapered and only the outside
is square. I think what you get depends on the amount of wear on the
rolls that made it.

Can you specify angle bent to a known radius from flat strips?

Square tube has some fairly loose specs, hot rolled product is even looser.

ASTM specs for tube call for the corner radius to be no more than 3x the
wall thickness. This means that a 2" square tube with .250 wall could
have 3/4" radius on each corner with only 1/2" of flat. This would look
more like a mildly deformed piece of round pipe than a traditional
square tube. What this means is that the mfg can make most any
reasonable radius on the corners and it will meet spec. It also means
that you can not depend on the radius to be the same from lot to lot.

When they mfg square tube they take some slit flat stock, roll it up,
weld it, then run it through a 'turk's head' roller to make it square.
If the slit stock is a bit narrow, the round portion will have a smaller
diameter, the resulting square section will have more rounded corners.
Since the mfg buys his steel by the pound, they have incentive to use
less, results in rounded corners on the cheaper tube.

Hot rolled angle is even worse. The only dimension that you can
reasonably count on is the 90 degree corner, and even that varies some.
The leg length can vary considerably, a 3-3/4" leg length on 4" angle is
fairly common. The inside shape is done with a roll that will vary from
one rolling mill to the next, multiple rolling dies at the same mill may
be more or less worn so you can't even count on the shape being the
same. Some will have a very large radius in the corner, some will have
tapered sides, some will have a smooth rounded edge, others will be
almost knife sharp. Most of this product is made is US mini mills from
scrap or imported. Neither is what I would call a 'prime' producer.

The horror story: we set up a robot to weld a frame that included some
4" angle brackets. The position was fixed by a stop block on the 90
degree face, the robot welded the lip. Things started out ok, then we
had a series of weld failures on the angle bracket. It seems that the
robot expected 4" legs, the low side tolerance was around 3-3/4". The
robot was welding a bead on the base metal, never even got near the
angle. We had to put in a "sense" op in the program where the robot head
moves in to find the edge, then starts welding. Slowed it down
tremendously, gave up on that. Finally had the robot weld the back side
to position the part, did a final edge weld manually.

It's amazing what you learn when you buy full truckloads of material and
then get to do the quality control after it has already been cut to
size. Sigh.

thito01 wrote:
Can anyone point me to a table with the standard radius for corners for
different steel forms?
I want to place 2x4 tubing inside either a 3" or 4" angle iron and don't
know if the inside radius of the angle iron will allow the 2x4" tubing to
set 'flat' on both legs of the angle iron.


TT



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Brian Lawson wrote:

On 27 Nov 2008 01:18:32 GMT, (thito01)
wrote:


Can anyone point me to a table with the standard radius for corners for
different steel forms?
I want to place 2x4 tubing inside either a 3" or 4" angle iron and don't
know if the inside radius of the angle iron will allow the 2x4" tubing to
set 'flat' on both legs of the angle iron.


TT


Hey TT,

Varies by producer, and not only that, on "most" standard angle, the
"legs" are tapered and not of constant thickness, so it won't form a
90 degree "inside" corner.

Take care.

Brian Lawson,
Bothwell, Ontario.
Yep. And even the outsides aren't 90 deg. At least on the aluminium
I've used, some 3 x 3 x 1/4.
...lew...

thito01 had written this in response to
http://www.www.rittercnc.com/metalwo...ms-153380-.htm
:
It sounds like I am in need of a solution instead.

The application is simple. A small equipment trailer made out of iron 2x4
tubing. I wanted to mount the axle springs on a sub-assembly made from
angle iron that will then be bolted to the 2x4 tubing. If my needs change
in the future, I can then move the sub-assembly forward or backward to
adjust the tongue weight for the new piece of equipment. So, I needed the
inside of the angle iron to be true instead of the outsides. Is there such
a thing? Or, should I just take some of the 2x4 tubing and cut it
diagonally to create two "L" profiles? Or weld two flats together to make
the angle?

I wanted to bolt though the sides of the angle iron and though the tubing.
Maybe just using some flat and bolting vertically on each side (front and
back) of the spring hangers would be an easier solution.

Maybe, just forget it and weld the spring hangers and just cut them off
and replace them if I need to change the function.

TT



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On 28 Nov 2008 03:24:43 GMT, (thito01)
wrote:

thito01 had written this in response to
http://www.www.rittercnc.com/metalwo...ms-153380-.htm
:
It sounds like I am in need of a solution instead.

The application is simple. A small equipment trailer made out of iron 2x4
tubing. I wanted to mount the axle springs on a sub-assembly made from
angle iron that will then be bolted to the 2x4 tubing. If my needs change
in the future, I can then move the sub-assembly forward or backward to
adjust the tongue weight for the new piece of equipment. So, I needed the
inside of the angle iron to be true instead of the outsides. Is there such
a thing? Or, should I just take some of the 2x4 tubing and cut it
diagonally to create two "L" profiles? Or weld two flats together to make
the angle?

I wanted to bolt though the sides of the angle iron and though the tubing.
Maybe just using some flat and bolting vertically on each side (front and
back) of the spring hangers would be an easier solution.

Maybe, just forget it and weld the spring hangers and just cut them off
and replace them if I need to change the function.

TT

You don;t want "angle iron" you want "steel shapes", "L shapes" in
your case. Google on "steel shapes" to get an idea of what is
available.

Cheers,

Bruce
(bruceinbangkokatgmaildotcom)

On Nov 27, 10:24*pm, (thito01) wrote:
...
Maybe, just forget it and weld the spring hangers and just cut them off
and replace them if I need to change the function.
TT

Why not fabricate two or three sets of hangers and weld one set on
now. Mount the springs with anti-sieze on the bolts and cottered
castle nuts. To move them, flip the trailer over, weld on another set
and move the springs. I think squaring and aligning the axle assembly
to the tongue would be hard to do with the complete, installed axle
but simple for four hanger lugs strung onto a long threaded rod..