Cleaning parts before silver soldering (degreasing)

[dbb-the-bruce]

I'm looking for a simple, common (cheap) cleaning protocol prior to silver soldering small brass parts (think just a few steps up from jewelry making). Ideally it would be just a bath and a rinse prior to fluxing and soldering.

I need to remove finger prints and oils from machining processes.

I've tried soap and water, DNA, windex with varying degrees of success.

The parts can be somewhat complicated and already have a pretty precise fit and are small - hence I don't want to do an abrasive cleaning.

Seems like I just need to find the right grease/oil dissolving solution.

Thoughts and suggestions?

 

[Lo-Fi]

Acetone is very hard to beat. It's cheap, relatively safe, readily available and very effective

 

[dbb-the-bruce]

Acetone is very hard to beat. It's cheap, relatively safe, readily available and very effective

I'll give it a try today.

Should the acetone be "rinsed" off (distilled water?) or let it evaporate off?

 

[Lo-Fi]

It evaporates very readily and quickly, no further cleaning required. I buy 100% "pure" stuff in 2 litre tubs so at least I know there's no silly perfume or anything mixed in. Love to see what you're working on!

 

[4ssss]

Brake cleaner.

 

[C-Bag]

Brake cleaner.

I use brake clean for powder coat prep and buy it by the case. For me it’s easier than acetone because it’s in a spray can. Like acetone it dries really fast and leaves no residue. I use it for cleaning aluminum before welding.

 

[Lo-Fi]

A word of caution with brake cleaner, particularly when welding:

Tetrachloroethylene, a deadly danger in brake cleaner | Envirofluid

Tetrachloroethylene (TCE), which can be found in some brake cleaner, carries serious health and safety risks through both short-term and long-term exposure.

envirofluid.com

I believe that particular chemical is no longer so widely used, but my attitude is why take the chance? You know what you're getting in a bottle of acetone; brake cleaner could be many different compositions, some of which are potentially quite harmful. I've never seen a pro welder clean parts with brake cleaner either, which I think speaks for itself.

 

[C-Bag]

You‘re right, in CA it’s been banned. So brake clean here doesn’t include it. But I’m so paranoid of all chem etc I don’t weld in enclosed spaces as everything about welding or soldering is highly toxic. Wanna scare the pi$$ outta yourself read about manganese poisoning caused by welding: https://www.cdc.gov/niosh/topics/welding/default.html

i first came on to this when I was doing search’s for welding rod and this class action suit kept coming up against the metal manufacturers. Turns out manganese is added to make steel easier to weld and it attacks the brain and causes Alzheimers like symptoms. Then there is the thorium used in tig welding. Acetone is no good for you either and none of these things should be used in an enclosed area.

 

[dbb-the-bruce]

@Lo-Fi - What I'm working on: A slip joint connector thingy.




That was today's project. The pin was soldered in after I made the block halves and drilled for the pin. This is really just more learning to fabricate (silver solder) at a model scale. All and all it came out pretty dang good for a first attempt. Soldering mistakes this time was too much solder and too hot.

After making the parts every thing fit really well with tight joints. The first bit of solder flowed and worked great, so I hit with more (of course!). At that point ended up with a lot to file away and the whole thing got a lot more sloppy by the time I made it fit.

Cleaning on this one probably didn't mater that much, but I used acetone like you suggested and had no issues with it. I've also been trying to make brass dominoes with enameling. The enameling is really fussy about oxidation and contamination. I'm going to give acetone a try the next time - when I try again.

Thanks!

 

[mikey]

Two things I've learned for small joints like that. First, the solder will follow the heat source so heat the part from below and apply solder from the top. Second, once the solder begins to flow, remove the torch. If you keep adding solder and keep the torch in place the solder will continue to flow towards the torch and you'll have a big mess, both underneath and on top. Our job is just to get the solder into the joint, that's all, and it doesn't take much.

I use Acetone for cleaning before soldering, too. Use gloves.