Heres the situation, Im new to the board and to tig welding and have no one around to help me in person. I just got a Lincoln precision tig 225 and my first stainless project is some parkerizing tanks made of 16ga 304 stainless sheet. I bent them up and "just" have to weld on the 8"x8" end caps. There is multiple problems but Im just trying to make this work and learn from it and looking for any advice. I havent been using any filler and its gone ok 3/4 of the time but here and there I'll do a stretch that just will not keep from creating holes and wont join. What are my options for fixing the problem areas without making the holes bigger and making the problem worse. I just need the freakin thing to hold liquid and not leak.
Current settings:
45-50amps
5-pps pulse rate
1/16" 2% thoriated tungsten
No. 7 cup ( biggest Ive got)
15 cfh
Ive been able to do some "decent" welds with mild steel and alum, but this stuff is kicking my butt! Any advice is much appreciated. Thanks
Low amperes and clean material. I would also try to purge it, if possible. It does help on stainless and with purge you can prevent creating holes quite well.
Yes definitely clean the edges. Are you able to get a hand inside the tank? If so, feed your filler rod from the back side and arc up right on the tip of the filler. Do little sections at a time.
When I first learned how to oxy/acetylene weld,
I practiced by purposely burning holes in metal and then patching the holes.
This taught me torch control better than any other method. I got really good at patching holes.
So, when I transitioned to TIG welding, I had torch control down to a science.
The only difference was that I was now using an electric flame instead of a gas flame.
My advice is simple...
1. Get some scrap metal.
2. Purposely burn holes in it.
3. Learn how to patch the holes.
...your problem is nothing more than learning how to control the torch. Don't watch the torch, watch the metal...
In tig welding in contrast to stick welding, the diameter/thickness of the filler metal can change independently of the amperage. This allows for 'melting off' the filler with low amperage. Almost a simulation of slow motion during the deposit.
Thanks for all the tips and advice, I just found some .035 stainless mig wire that I forgot about and Im going to give that try on some scrap pieces. Am I in the ballpark as far as amps go if Im using that thin mig filler wire? Thanks again
You should be able to weld that 16 ga. as low as 35 amps (though you may be more comfortable a bit higher... Kind of a preference issue) and still have no problem feeding .035 filler when needed.
It may take longer to establish the initial puddle, but since heat move so slow in stainless compare to carbon steel, once you have enough heat to establish the puddle, it'll hold enough heat to move along just fine.
I've said before, no two of us do it quite alike, so take all advice for what it's worth. Some may not work for you at all, and some may need to be adjusted to fit your style.
One other tip: LOTS of tacks. That 16 ga flexes easy, and the heat from your weld will open the gap, leading to keyholing, wich is the enemy of a fillerless weld. I'd tack every inch to inch and a half for that outside corner, then weld tack-to-tack moving around a lot, to let each weld cool before welding near it again.
You'd be surprised how few folk are familiar with backfeeding a weld. It's a lot more common in the pipe trades than a typical job-shop, or home garage.
I can't do it worth a crap, myself, because I've needed it so rarely.
Hi to all who posted a reply to this post.
I have posted almost same on other welding forums and no one responded.
I will be trying out the techniques/advise soon.
A big thanks from me.
Best Regards from Scotland
I did this one, 20ga 304, mostly no filler. Used aluminum angle for backing and made sure everything was very tight on the fit up. If the fit up was loose or you got going too fast it's easy to have the problems your having. Since you already have holes, I would use copper to back the weld and just go carefully.
don't laugh, you can use 3/16 or 1/4 flex copper tube that fits in the corner, just wrap it with aluminum foil to conform to the corner and clamp it or use HVAC foil tape.. the foil tape will leave a mark ..
your local welding supply should have a backer tape for thin stainless.. it's pretty common.
When I first learned how to oxy/acetylene weld,
I practiced by purposely burning holes in metal and then patching the holes.
This taught me torch control better than any other method. I got really good at patching holes.
So, when I transitioned to TIG welding, I had torch control down to a science.
The only difference was that I was now using an electric flame instead of a gas flame.
My advice is simple...
1. Get some scrap metal.
2. Purposely burn holes in it.
3. Learn how to patch the holes.
...your problem is nothing more than learning how to control the torch. Don't watch the torch, watch the metal...
Agreed 100%.... If you can master torch control you can do anything, the above method is how I taught myself how to fill holes years ago. Now when I have a repair job holes or gaps don't worry me one bit. I also use mig wire or .035" fill rod on thin stainless. Pulse is a great tool bit I'd try to master without it first.... Learn what to look for, read the puddle and metal
I weld stainless, stainless and more stainless...Food Industry, sanitary process piping, vessels, whatever is needed, I like to make stuff.
ASME IX, AWS 17.1, D1.1
Instagram #RNHFAB
When I first learned how to oxy/acetylene weld,
I practiced by purposely burning holes in metal and then patching the holes.
This taught me torch control better than any other method. I got really good at patching holes.
So, when I transitioned to TIG welding, I had torch control down to a science.
The only difference was that I was now using an electric flame instead of a gas flame.
My advice is simple...
1. Get some scrap metal.
2. Purposely burn holes in it.
3. Learn how to patch the holes.
...your problem is nothing more than learning how to control the torch. Don't watch the torch, watch the metal...
Agreed 100%.... If you can master torch control you can do anything, the above method is how I taught myself how to fill holes years ago. Now when I have a repair job holes or gaps don't worry me one bit. I also use mig wire or .035" fill rod on thin stainless. Pulse is a great tool bit I'd try to master without it first.... Learn what to look for, read the puddle and metal
I weld stainless, stainless and more stainless...Food Industry, sanitary process piping, vessels, whatever is needed, I like to make stuff.
ASME IX, AWS 17.1, D1.1
Instagram #RNHFAB
