Welding Tips and Tricks

I have to weld some pieces of 1/4 inch thick aluminum plate to pieces of 1/8th inch wall aluminum channel. Do I need to pre heat the 1/4 inch? I have a piece of plate steel under where I need to weld to prevent blowout of the thinner stuff, so if I can just crank up the amps a little bit more that would be easier for me than pre heating.

But if I have to pre heat, I suppose I'll have to....

Other Steve

That's not enough detail for a solid answer. If the purpose is simple, and you have a steel backup, I'd say "crank it up and burn", but that's a guess based on the information given.

BTW, I used something today I'll bet you recognize... 1" Gaffer's tape by Progaff...

Steve S

We use Progaff!. It's a good gaffers tape. Shurtape makes a good gaffers tape too if you can't find Progaff. We can order either kind for you if you need more. We can probably get it cheaper too. What were you using it for?

I'll post the plans of what I'm making. It's basically a 4 inch by 4 inch square of aluminum welded into the corners of some 1/8th inch thick channel. The channel is a table frame and the plates join the bottom corners and also act as leg joiners/supports. It's a 1/4 inch thick because I'm drilling and tapping the plate to accept leg bolts. On some prototype versions the plates were as thick as the channel, but I had to weld nuts onto them. That wasted a lot of time when I can just drill and tap.

I'll post the prototype process photos over in the "Projects" thread in a little while.

Other Steve

Just did some 1/4" today.... just burn away... no pre-heat necessary. I'd post pix but tired of having to re-size them to fit this site.

I've also got the remains of a roll of Shurtape 2" I'd love to find more of. Make duck tape look like cheap masking tape with bad glue.

You won't believe what I'm using the Progaff for... Temporary vacuum-tight... I'll have to use pics to explain over the next few days.

The Progaff was accidentally left to me by an x-ray crew...

Steve S

Gaffers tape is amazing stuff. A thousand times better than any duct tape and all sorts of uses as you've just said. I never would have thought of it for that particular use, but it works! There's even a type that only has adhesive on the outer edges, none in the middle, so you can tape down cables to the floor and not get any sticky residue on your cable when you go to take it up.

This is where we get it from....http://www.rosebrand.com/

Look on the left side of the page for a column labeled "Production Supplies" , click on "tape" and then click on gaffers tape.

Any type of theatre or movie production supply place will also carry it, but they most likely buy it from Rose Brand too and mark it way up.

Other Steve

I mig tons of alum at work with a miller 350p all thicknesses. From 16 gauge Thru 3/8. Can be a bit tricky with different wall material. I usually run the voltage for the heavier stuff and then just focus the arc there and roll it into the thinner material. Haven't used a pre-heat for it. Just my $.02

Thanks gocirino!
Thanks jimbob!