Small deep tray, purge?

[Hitch]

I need to make a 316 tray, 1.2 or 1.5. Its a bit on the small side and deep to weld on the inside nicely i think. Unfortunatly, only two of the long edges are folded, the other two welded on and the verticle corners need too be welded also.
I guess i ought to be purging the inside of this one?

Id prefer to fold the lot and have minimal welding personally.

 

[hotrodder]

Several alternatives to purging come to mind but it depends on what it's for. I would normally create an argon dam adjacent to the sides needing welding but if full pen welds aren't needed could clamp some ally or copper to the back of the joints.

 

[Hitch]

I normally put an ally backer in. Its going to be in water probably 50% of its time, even the slightest burnthrough is going to be bad.
Not keen on thin stainless, dont get enough practice at it

 

[Welderpaul]

Whats stopping you folding all four sides?

 

[Paul.]

A close fitting piece of copper is better, ally and brass can spit if the arc touches it and contaminate, I make loads of chutes, trays etc, that need to be sealed for hygiene purposes but dont need to be particularly strong, a close joint will help, I would use 16swg by choice and probably run the weld vertical down, is it food related?.

 

[Hitch]

Strength isnt much of an issue. Food, well, drink. So yes.

I was going for the 1.5 to make life easier for myself, and less chance it will be a mess with 4' of weld on it!

 

[Shox Dr]

Several alternatives to purging come to mind but it depends on what it's for. I would normally create an argon dam adjacent to the sides needing welding but if full pen welds aren't needed could clamp some ally or copper to the back of the joints.

I've used an other piece of folded SS to back the inside of corners where I needed to stop "sugaring" It works very well, with a good fitup and no rod

 

[Rick]

I've got to weld a 0.9mm stainless steel 1meter cube. Its welding to 3mm angle on the corners. I'm not looking forward to it.

Have you got a helper? I get a gas lense on my purge line and have him follow me on the reverse side. (give him a mask and he can see where it glows). Works fine for me

 

[Freshfabrications]

what exactly are the dimensions and what is it for? chemical? Food?

when i was making huge extraction canopy's for industrial kitchens etc, from 20 and 22 guage as the boss was a tight wad. id set my machine pulsing really fast like 900 Hz,30-40% peak at about 50 amps, id tack up the joint and tap the tacks into good tight alignment, argon at 8lpm and torch with tungsten out 12-15 mm laid at an angle and run it in, with generally little or no burn through.

If you need full pen and chemical or food quality on the root penetration, try getting a nice clean peace of angle and fit it in side the inside corner so it makes a little cube channel and masking tape down both seams, then put in a purge line from your reg and tape that too, purge at say 3-5 lpm for a Min or two per meter for safety then weld as you would for full penetration.

let me know if you make use of the angle on it worked for me a lot on food stuff.