[Coldman]

I am building a small r&d refrigeration unit to test chill times of various food products in water or brine. This requires a small stainless steel tank to fill and refrigerate said water or brine. I thought this is a good time to give the Solar Flux B product a go and review for all my welding cobbers out there.
I asked the local sheet metal shop to donate a rolled section of 300mm diameter 1.2mm thick 304 sheet which he did considering the amount of work he gets out of me.

Here is the stuff next to the tube which I speed tacked

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The instructions said to mix it with alchohol, methyl alchohol preferred. I had ethyl so that's what I used.

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Looks like builder's cement. Mixed it into a paste like thick cream and brushed it on the inside of the joint.

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Welding OK, 1.6mm 2% lanth, about 40 amps on the pedal until one of the tacks popped and the joint opened up. Gunk started coming through but welding ok with increased amps but I stopped and closed up the joint with the BFH, re-tacked before continuing.

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This is the residue coming down while welding. You're gonna have to get this out if the part is closed in by welding. How do you do that?

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This is the joint after welding before cleaning.
Hand wire brushing was not effective due to some of the residue turning to a glass like consistency that stuck. A wire wheel got it all off.

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Cleaned with wire wheel. It actually looks alot better in real life than on the photo. I tried many shots but couldn't really capture it right. The weld was full penetration, no lack of fusion or porosity even though it looks like it on the photo. The bead on the inside is not smooth and there is still some tarnishing which the wire wheel left but a flap disc would dress it up nice I recon.

The process took longer than clamping a backing bar but did the job in the end. Maybe not the best for sanitary work...
I guess it has it's place.

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Who put that there? That's a distraction!

[rufflivin]

Your work is looking good.

[MosquitoMoto]

Coldie deserves a crownie!

My own experience with Solar B is similar to yours. It's better than nothing but seems like a lot of farting around and the results aren't exactly ideal. I find that mixing it up good and thick and laying it on very thickly delivers the best results.

I have used it on a stainless motorcycle exhaust that would have cost me a heap of argon to purge properly. Not what you'd call a 'sanitary' application and not a load bearing part, either. Will only ever be used by me so if corrosion sets in, no biggie.

Oh, and I mix mine with metho...


Kym

[exnailpounder]

I see you saved a little ethyl alcohol for yourself. I got thirsty just looking at it.

[Coldman]

It's denatured, better stick with the crownies.

[rick9345]

For me it has been trying to get right paste mix/consistency
AND low heat/speed HAZ correct

[exnailpounder]

It's denatured, better stick with the crownies.

AndersK said they drink it in Sweden where he lives. Said it makes them smell like cat piss.

[Rituchim]

whats does it supose to do?
replace purgging with argon?
for somethin this size if i wasnt into purgging i would weld from the inside (more important to the surface the food touches,
and clamp a piece of copper or aluminum from the other side.

seems to me like the mith of aluminum welding rods nice idea and thats all.

[Coldman]

Yes its supposed to replace purging. A tin of the stuff is cheap so I thought I try it out that's all otherwise I would have welded like you say. In this case its an r&d item for use in the shop, not for customers so the finish really does not matter. But its good to explore new ideas and technology I think even if it confirms what you are already doing is best practice.

[Sandow]

I wonder if you could use copper tape like this:

http://www.amazon.com/inch-yds-Copper-F ... pper+strip

The adhesive would slag but it might give you the protection you need for a quick pass anyway.

-Sandow

[Rituchim]

Yes its supposed to replace purging. A tin of the stuff is cheap so I thought I try it out that's all otherwise I would have welded like you say. In this case its an r&d item for use in the shop, not for customers so the finish really does not matter. But its good to explore new ideas and technology I think even if it confirms what you are already doing is best practice.

you dont have to purg everything. if the fit up is tight take small angle iron or aluminum(better), tape it from the inside so it wil make a closed triangluar tube with the tank. close the ends and now u only purg a very small tube... blast away a quick fusion tack and its gold.
inovation is important but if i were u i'd try this flux on scrap pieces first.....just in case (i do test runs alot!!!)

[Coldman]

Very familiar with all methods of purging and and back bars. Just trying out the new product to see what its about.

[Coldman]

Using scrap is not as interesting or informative as a real application particularly as a post on the forum so I waited for quite a while for a real application to come along where the finish did not matter to me.