Welding w/o warping
Welding w/o warping
(OP)
This is the problem I have. I need the advice of experienced welder
I have a project to build an aluminum door for an aircraft. It is an airstair door. Approx. 4 ft by 5 ft. It is made up of many sheetmetal parts all 6061. All the same thickness .063. Some parts will be bent to shape on a brake. Others will be cold formed to shape using a shrinker stretcher. All the parts will then be put in a jig fixture for welding, which will result in essentially a shell. The problem that a previous manufacturer had was warping.
I saw at one time a welder first tacking together, than welding little sections (approx 1 inch) at time at opposing locations. I think it was for allowing even heating of the aluminum. I would think with the addition of "clamping until cooling" that this might reduce the warpage.
Is this correct?
Karl
I have a project to build an aluminum door for an aircraft. It is an airstair door. Approx. 4 ft by 5 ft. It is made up of many sheetmetal parts all 6061. All the same thickness .063. Some parts will be bent to shape on a brake. Others will be cold formed to shape using a shrinker stretcher. All the parts will then be put in a jig fixture for welding, which will result in essentially a shell. The problem that a previous manufacturer had was warping.
I saw at one time a welder first tacking together, than welding little sections (approx 1 inch) at time at opposing locations. I think it was for allowing even heating of the aluminum. I would think with the addition of "clamping until cooling" that this might reduce the warpage.
Is this correct?
Karl





RE: Welding w/o warping
On the other hand, if welding is definitely required, then stitch welding, as you have described, will reduce distortion. The key is to make as many small tack welds to tie everything together before welding out the structure. Then, on long beads, skip weld and then go back to fill in the skipped areas. Of course, the heat affected zone around the welds will be weaker than the parent material, unless post weld heat treating is performed. That heat treating opens up more possibility of distortion unless the weldment is rigidly held in a massive jig during the heat treating process.
RE: Welding w/o warping
Thanks for your response
RE: Welding w/o warping
Efraim
RE: Welding w/o warping
RE: Welding w/o warping