Re: Square tube needs a curve

[Slick 50]

1.5 inch square tube, .085 wall ( I think)... I need to put a slight curve in 3 pieces 20 feet long.  THe curve needs to match for all 3 pieces.

The curve is slight. Over the length of 20 feet the center would be bow'd out about 25 inches off center from the ends.

I prolly can only offer the obvious here, but I would think that constructing a mandrel of the configuration you would like and applying heat to bend it a little at a time would work.

If you aren't too worried about minor distortion I would think you could bend it without filling the tube with sand. It would almost spring 25" over 20' without too much effort, but you would have to consider uniformity across three pieces.

[enjenjo]

1.5 inch square tube, .085 wall ( I think)... I need to put a slight curve in 3 pieces 20 feet long. THe curve needs to match for all 3 pieces.

Clamp the pieces side by side, lay the tubing on your concrete, with a 1x4 flat under one end, another about 6 ft from the end. back you pickup tire onto the tubing rolling almost to the second 1x4. Insert another piece of 1x4 6 ft from the second, and so forth down the length of the tubing. Should come out with a gentle curve from one end to the other. You can adjust the curve with block spacing and height.

[Darkman]

I watched Monster House the other day and they had a homemade rig that used three rollers about 12" long and maybe 3" diameter. The center roller was attached to a big steering wheel abot 3' in diameter. It sat on top of the tubing. Below the tubing was the other two rollers one one each side of the top roller. Pressure was applied but I can't remember which roller they used. The tubing was fed in and the center roller with the big steering wheel was turned which pulled the tubing through and formed a long graceful curve. More pressure equaled more curve. It looked fairly simple to build. With the roller width I would think you could feed all three pieces at one time making identical pieces. Also I believe that with equal pressue on the same size tubing would produce dupilcatable results. Just index the pressure screws.

Was I totally confusing?

[enjenjo]

Was I totally confusing?

No perfectly clear. Of course my way is more redneck friendly.

[Darkman]

Now what would a OHIOian know about Rednecking. Pensacola is definately Redneck country. Amazingly your idea qualifys.  

[river1]

here is a thread about building your own ring roller

http://www.hobartwelders.com/mboard/showthread.php?s=&threadid=5343&perpage=15&pagenumber=1


the guy is in AZ maybe you can get a hold of him and he can roll them for you.

later jim

[Darkman]

Yeah but if you used a screw you could calibrate it and it would be easier to duplicate settings.

[river1]

the guy with the roller project updated his post concerning calibrated bends

http://www.hobartwelders.com/mboard/showthread.php?s=&threadid=5575

later jim

[Slick 50]

That roller is sharp!
I wish I had a use just so I could build one.

[Dirk35]

Perhaps you havent thought of this, but where I live, its kinda a natural......

At the local farm store, you can get 1" square tubing circles to build round bale feeders out of.

I dont know how much curve your actually needing, but those feeders are usually a circle about the size of a small car. Imagine a hula hoop for a Volks Wagon beetle, to get the idea of the size.

I know you said you were wanting 1 1/2", but you can get these in both round and square tubing, and you wouldnt have to do much to it if the curve fits your needs.

[Dirk35]

Oh yeah, the one I showed is a 6'6" diamater, they go up to 7'8" also I seen listed when I just did a search for "round bale feeder".

[STREET ROD MD]

1.5 inch square tube, .085 wall ( I think)... I need to put a slight curve in 3 pieces 20 feet long.  THe curve needs to match for all 3 pieces.

The curve is slight. Over the length of 20 feet the center would be bow'd out about 25 inches off center from the ends.

I am building the last gate for the house here out front at the cul de sac .

The tubes sat at a guys shop since december 03. I picked them up yesterday so i could actually get going on the build.

If you call a wrought iron builder, They have the roller that you need.
Or if you are going to the pomona swap meet bring the tube and I'll bend it for you..... long way to bring tube. Wrought iron shop is the best bet..
Good luck....... Manny ------------

[Jimc]

I recently read an article in Streetrod Builder magazine about bending square tubing.
Their take on it was to fasten(tape) a round rod to the inside (inside bend) and gradually bend in vise to desired curve.
You just adjust the length of tubing protruding from the vise towards the curve and apply pressure until you get the curve for the length you want.
By turning the tubing and rod assy in the vise you can bend from right to left or verticle from a simple curve to an S shape.
I have not tried it but the article was about building a griid for floor in a 32 Ford,
One curve was mated at the firewall to clear the belhousing of the transmission, and another at the body of the transmission.
The magazine even showed one curve that went wrong.
Just in case you want to pick up the issue for reference, it is the March 2004 issue with a center door Model T on the cover.

Jim

[58 Yeoman]

Hopefully, here are the pix that JimC mentioned.

[58 Yeoman]

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