[ogorir]

copper is still almost always 4x the price of alu though. also, you probably wont notice a price change on anything but wiring in the near term. sheet and bar stock doesn't see nearly as much volume.

[DanW]

Yeah i reckon a bit of aluminium sheet might be the go instead of copper sheet or stainless flat bar. might just have to hunt for some offcut/scrap and screw it down to the steel frame.

On another note, I've noticed on one corner of the SHS frame, the top weld has cracked longitudinally, the whole length along (have not even used the table for anything yet and those welds were done last so havent twisted or distorted the frame or legs to get the bottom shelf frame in afterwards)

all 3 other corners have no cracks, and the fillet/outside corner welds on the same corner have no cracks either- just the butt weld on the top of the join. could this be a result of using 316L ss electrodes on mild steel?

I left these welds for last, basically tacked the frame together while clamped up, welded the outside corners alternating diagonally in sequence, then the inside corners alternating again, then i put the legs and bottom frame in and finally did all 4 of the topside butt welds and then flipped it over and did all 4 of the bottomside butt welds. maybe I should have done top then bottom for each corner, and alternated corners?

electrodes are 2.5mm (3/32 i think) and amperage around 85-90A DCEP

no preheat/post heat

[ogorir]

another option would be to buy a nice 2x3' chunk of 1/2" mild steel, drill and tap the corners, and get some thinner sheets of alu, stainless, and copper and just bolt on what's most appropriate for what you're welding.(counter sink your sheets and use allen head bolts) as jody's video this week points out, the copper will (help) prevent arc strikes, too.


as far as that weld cracking... it shouldn't do that I have no experience with SS stick rod, so I'll let someone else chime in on that. my experience with SS TIG though says as long as you're shielded, you shouldn't have any cracking issues using stainless to weld mild together.

[kermdawg]

nother option would be to buy a nice 2x3' chunk of 1/2" mild steel, drill and tap the corners, and get some thinner sheets of alu, stainless, and copper and just bolt on what's most appropriate for what you're welding.(counter sink your sheets and use allen head bolts) as jody's video this week points out, the copper will (help) prevent arc strikes, too.

That was one of my main theories behind using copper. It wont contaminate anything you weld on, be it mild steel, stainless, or aluminum. Cost a bit more, but no changing sheets or worrying about welding your aluminum on a mild steel bench.

[karlevo8]

certainly not the worst ive seen and if it square your halfway there ,itll be alot easier getting practice now you have a table

[delraydella]

This is a good example why I like plywood tables. They can be put up in a hurry in almost any configuration you need and when the current set up is done, you unscrew it and reconfigure it for the next job. Or just throw it away. You can also clamp wherever you need to and screw down fixtures anywhere you need them.

If I can't get MDO ply, I'll always use A/C because it's nice and flat. It also weighs a lot less than CDX which helps this old farts back out. Note that I always spray my plywood tables with a flame retardant called Fibre-Shield before I start to weld. I'll post their web site if anyone is interested.

On this table is the start of a couple of aluminium truss towers for a public tv station. They are 2'6" x 2'6" x 15' high and are made out of 1 and a 1/2 square tube for the base and 1 and a 1/4 schedule 40 pipe for the uprights. The centre spreaders are all notched to fit. Everything will mig welded with a 30a Spoolgun. You can see my (almost) brand new Millermatic 252 in the background.

Steve

[TheExpert]

A steel welding table is a basic necessity for any welder's workspace, since welding on a wooden surface can present a very real fire hazard. In addition, with a steel table, the welder's work clamp can be attached to it, and parts placed on the table will be electrically connected with the table's surface.

[TheExpert]

I have same thought as kermdawg. You provide good information.