Welding Tips and Tricks

I've finally gotten in decent shape w/my little Diversion 165 and gathered materials to make a welding table. For the top I decided to stretch the machine and see if it would weld 3/8" (3/16" is the stated max for the Diversion). A little preheat with a torch and presto, good enough to weld a small piece of 3/16" angle iron (1-1/2") that I welded for practice, with no filler, on to the bottom of the plate. It took maybe ten seconds to get a puddle going, and I pushed the puddle from the plate to the angle iron. Worked fine with no burnthrough of the angle iron.

It was only then that I thought the plate seemed a little off. Lo and behold, it's only 3' long but warped almost 1/4" along its length.

My question is - could that little bit of welding warp a plate that thick? Or is it more likely that it came that way? I hate to bitch about a problem that I caused, especially since that piece is ruined.

Another question, am I using overkill with that thick of a plate for that size of table?

Your opinions will be gretefully received,

Chuck

yup, you probably warped it. the preheat and constant heat input of starting at one end and going to the other pretty much guarantees warpage.

I'd consider 3/8" to be a minimum for a welding table fi you're going to use if for fixturing, fabricating, ect. you want it as solid as you can get.

next time around, skip around. I'd use a mig for this so you can keep the heat input down w/ the zap and stop technique. set the machine 20-50% hotter than you normally would then just pull the trigger until it puddles, get off the trigger, move over 1/2 the diameter of the puddle and do it again. only go about an inch and a half, then move somewhere else. you don't really want a ton of penetration into that table top, or else you'll warp the crap out of it. our table is 3/8" plate welded for 1.5" out of every 6" to 2" heavy wall (3/16", i think) w/ 4" 1/4" wall sq tubing. if you weld to both sides of the sq tubing, you should have no strength issues only welding for 1.5" of 6" and you shouldn't warp the plate.

Thanks for your reply ogorir; I probably didn't explain my experiment too well. I only welded that small piece of 3/16" angle iron, for 1-1/2" along each side, when it was in the middle of the plate. So not very much welding altogether on it... the plate never recieved heat to its end because I had my forearms resting on it. However, it was up on blocks rather than on a concrete floor. With that extra info, would you still say that my welding probably warped it? Is it better to keep it flat on the floor?

Thanks,

Chuck

I dont know if it'll help ya, but I used 1" black iron gas pipe for my welding table top. Really saved on the cost, and you can space em out however you want depending on what your doing. I spaced mine out 6" apart and it works great!

Thanks, I have thought about the advantages of having spaces in the table that might help when a piece has some irregularities...

so, you welded the piece of angle to the center of a large plate? if that's the case, then yes, you probably warped it. by welding right in the center like that, you trapped the heat in the middle leaving nowhere for the metal to expand except to deform upwards.