Anyone have any tips for making the second pass on schedule 10 stainless weld els? The first pass comes out great. The welds are clean and dont have any grey contaminiation looking stuff in them. Heat marks are nice and even. Im welding them with 90amps and 308 rod. The joints are all coated on the backside with Solar flux b. When I make multiple passes, the welds become that greyish contaminated color. Also, it seems that heat control gets a bit harder..even if the manifold has cooled off in the mean time. Any hints as to what I might not be doing?

 

What are you doing as far as metal prep after running the first pass? As far as the heat control being harder after the first pass...I think that should be right, because with the second pass you are heating your filler metal which should be harder than your original base metal. So with your second pass, your going to have to use some more amps to melt the filler rod from the previous pass because it is harder than your original base metal.
GOOD LUCK!
Kyle

 

Makes sense on the heat control. I never really did much thought about metal prep for the second pass. What do you recomend? For the first pass I do the usual edge beveling, wipe it down with acetone and use flux like I mentioned before. I would usually weld the first pass of all the manifolds I was making at the time then go back to the first and start the next pass.

 

Im not yet a stainless man, so I really couldnt tell you what I would recommend as far as prep for the second pass. I would defenitely at LEAST wipe it down with acetone again though. Again, good luck!
Kyle

 

i read on here that, after the first pass you should brush the pipe with a SS brush as it cools down.

heres the thread. engloid gives a good step by step on how you should weld sch pipe.

https://honda-tech.com/zerothread?id=1119908

 

Yeah, brushing is all you need to do, as it cools down. Acetone will be useless. Any oils or anything like that which may have been left in the weld area will have already fucked up your weld or burned away by the time you put a second pass.

Why are you using solar flux? That ****'s as useless as wiping mud on the inside of your pipe.

BTW....I'm sure your turbo will appreciate it when chunks of solarflux break loose and go into the exhaust turbine while it's going about 100k rpm's

 

The manifolds get high temp coated and are sandblasted inside and out to clean all the residual crap out. I had always been told good things about the solar flux b. This is the first time Ive ever heard anything negative about it. Why dont you like it?

 

You won't be able to sandblast all the inside of the manifold.

Did you do some test pieces with the solar flux?

I have been welding 26" pipe at work for a couple weeks. Some other guys started the job and purged the inside of the pipe when welding. Of course this sounds good, but looking at the inside of the welds, it's very evident that they would not pass any type of inspection. They sugared up, are lumpy, have lack of fusion in many places, etc. You will get the same thing with solarflux.

Sure, it sounds good. It sounds like a magic fix. If it were, nobody would ever use argon. Solar flux is most commonly used in paper mills, where quality is not much of an issue. You will NEVER see it used in any food processing piping, as it simply isn't worth ****. It's about like communism. It may sound great, but in reality it just doesn't work for ****.