iv been welding 1.5" sch. 10 304 ss, using solar flux on the back of the butt joints, my issue is when i do a root pass, the solar flux comes to the top of the puddel and makes for a really ugly weld, i wire brush it and go over it with a filler pass and the solar flux agan comes to the top of the puddel, it makes it look like im over heating the weld but im only using about 60-75 amps for both passes, im using denatured alcohol with the solar flux if that helps any, iv tried on a practice piece of ss without solar flux and the weld comes out perfict, nice color, good penetration,ect..
any idea what i could try to stop the solar flux from comming to the top?
thanks
joe

 

I'd purge it instead of using solar flux

 

The question isn't weather to back purge or solar flux it, it's why is the solar flux comming to the top of the puddel,
I'll get a pic up INS a bit

 

I used solar flux on my manifold too. I noticed this happening to me on the first couple welds. What I did is made sure the flux was not right on the edge of the metal and I did not have a gap between the joint because I could see the puddle just suck it in when there was a gap. I Beveled the pipe to pretty much a wedge instead.

 

Any problems with sugaring? I'd figure that is where the flux really needs to be

 

heres a pic of some scrap i did , not the best shape welds but just testing the solar flux

 

Scrap the solar flux, its ****, purge instead.

 

i know purging is better, cleaner, ect. im trying to figure out why solar flux is doing this..
maybe im cacking it on too thick?, the seams are tight..

 

The reason it comes to the surface is because you are getting full penetration, at least in some areas, when you get full penetration the interior surface is molten, by nature of molten material impurities are brought to the surface, which is why you see the solar flux coming out to the top.

In other words, solar flux is gay, purging really isn't that expensive and is the proper procedure for full penetration welds on virtually everything.

 

Its perfectly normal for it to do that, it says it on there website that, that might happen. Have you gotten any explosions yet with it ? Fun stuff.

 

Dosent that stuff turn to almost like a ceramic material after is welded? Id be worried with that breaking off and possibly falling into the cylinders.

 

I wouldnt use it on an intake, but exhaust seems fine, alot of people are worried about the flux flaking off and going in the turbo, but my input is the flux that can flake off is so brittle and thin that it would just cycle threw the turbo without damaging the turbo.. Just my 2 cents