Welding 10 ga sheetmetel w/ accupulse

[flashburn]

Hi I am new to this forum, but I look forward to reading some good posts here. I have searched the forum and could not find the answer to my question. I was hoping somebody could help me out.
The problem I am having is with warping on a tail gate that I build for Trailking Livebottoms. I have made a hundred of these doors and every one has been bowed about 3/8 to 1/2 inch from the center to the end. I am welding an 8 gage doorsheet on a 1/4"x 1 3/4" tube. I like to weld it using accupulse with my wire speed at 325 ipm and arc control at 54 and arc adjust at 23. My co-worker who installs the door asked me to work on the warping to make his job easier. I have tried everything that I can think of. I have been able to reduce it a little bit by switching to normal mig. 21.5v 330imp, however I hate the splatter. Plus once I got use to accupulse it is **** going back to regular mig. I do fine dialing pulse in on anything else. I build the door on a jig the same shape and clamp the four corners down before I start welding the sheet on. I have even tried to blow air through the tube while welding. I also try to weld in increments of 12-18 inches,jump around and let it cool between. I was hoping somebody would have some ideas. The door tube in the picture looks warped as well.truck-slide.jpg

[shovelon]

Have you changed direction of travel?

[Portable Welder]

When ever you apply heat to one side of the tube your going to have warpage so your jig needs to be bowed the opposite way so when your done welding it warps straight.

Pulse welding will help control your heat input which will minimize warping but will not eliminate it, You can send things out to be annealed which will help some.

Whenever we build machine bases we always use thicker plates for the mounting pads so they can be machined afterwards to the proper tolerance.

Your best bet is to make a press over a big layout table and use jacks to bend them back straight.

[Country Metals]

How long do you leave the doors in the jig before you remove them?


The ways I get around large steel bowing is to:

1) offset the jig to the bow
2) press it back straight
3) weld both sides at same time
4) weld it down to a heavy table (1" or more) allow to fully cool before removing
5) pre/post heat