frame building

I am building a frame out of 2x3 and am wondering how to keep the frame from warping when I weld it up. I am building it on a table and have it jigged up. However, the frame seems to move (deflect) from the heat right after I weld it. Any suggestions?

then you dont have it jigged up.. a jig is someething that holds all pieces in place and not allowing them to move so they are exactly the same within 1/16 everytime. you just have it laid on some lines or up against some metal.

you should really invest in either HUGE c clamps and clamp it down all over, or de-sta-co clamps and utilize them like we do at work.

you might be welding too much at one time, i built my frame at school and just laid it on the cross members of the table, no tacks no clamps, my frame never warped once and nothing was off more than 1/32"

ya u need to get it jigged up.. clamp it down very good...

I am building this frame (backhalf) on a welding table with the frame laid on its side. I am welding short pieces of angle iron to the table and onto the frame to keep all the angles straight. This allows me to make the other framerail identical. Everything stays within the parameters when I weld it up. It distorts when I cut the tacks off of the table. Is there a welding sequence that I must use to minimize the distortion? Could someone post pictures of how to successfully weld up a frame? Thanks!

Clamp it down and tack all four corners of the tubing on all the joints. After you weld it don't take the clamps off until it cools down.

Originally posted by UnusualFabrication



Clamp it down and tack all four corners of the tubing on all the joints. After you weld it don't take the clamps off until it cools down.

Do I weld all three sides, let it cool, and then flip it over and weld the bottom side? That's pretty much how I did it but for some reason the metal didn't want to sit flat on the table after welding. Then ends of the tubing always wanted to lift away from the table. Ever have that happen?

you arent using enough clamps if its moving at all. built my backhalf on a MDF table with 1 piece of 2x3 clamped to the table and i tacked my pieces to the piece i clamped down, then fully welded em.. you can stick a straight edge down my backhalf and it wont be more then 1/16 out at any spot.

If you can, weld one side then weld the opposite side of that weld. As you weld the heat will shrink the metal and cause it to pull. If you weld the opposite side, it will cause it to pull it back and kinda counteract the first welds ill-effects.
When doing rectangular tubing I usually weld the top and bottom first since the miter joint will not be able the pull the tubing in any direction. Then I weld the sides. This seems to help minimize warping.

Also if you can fit the rail back into your fixture, slowly heat up the weld joint and let it cool. It should relive some of the stresses in the metal and relax it back into shape. Be carefully though, too much heat and it will make it worse.

Good luck
t

Tack the rails to the frame jig.