Commercial Flux

[dondiego]

I have several quarts of commercial flux made for swiping onto large copper pipes and fittings prior to being tinned/soldered. It is the consistency of Vaseline and looks a lot like it. I have used it in one of my pots during a casting session but was a little worried about using it if there was a chance of any acid eating at my molds or pots. Does anyone have any experience with this stuff?

[Outpost75]

I use a stick flux called Vitaflux, which was used in the printing industry in linotype machines. A stick fhe size of a roll of dimes will flux a ton of melt. I use a dime thicknessed slice per 50-100 pounds of alloy.

[ku4hx]

I used to have a quantity of what sounds like what you have. I never used any of it as flux because of the very reason you mentioned ... acid. It may be totally harmless but I'm going to let somebody else do the experimenting on their equipment.

Over thirty years ago I bought several hundred pounds of Linotype metal from a local printer; the threw in a little stick of what I know know as VitaFlux. All that Linotype metal is long gone, but I still have about 1/3 of that stick left. Over the years, I've used pretty much every fluxing material there is. But the VitaFlux is the very best. Works beautifully, no smoking and in a 20# pot it takes about 1/4 match head to work effectively. If I live long enough I'll likely buy one more tube. It is a mite expensive, but it does last a loooong time.

http://www.midwayusa.com/product/260495/ney-vita-n-flux-fluxing-compound-6-oz Seems the name may have changed a bit but as far as I can tell it's the same stuff.

[mdi]

Paste fluxes will not have acid (like acid core solder) and if it does it'll say on the label (at least none of the paste fluxes I've encountered). Acid flux or acid core solder should not be used on electrical soldering as the acid in the flux may continue to corrode/erode the copper wire after soldering. Try a dab of your flux and see if the lead coats/solders to the inside of your pot...

[dondiego]

I have tried it on 2 or 3 occasions and it seemed to work fine with little smoke and no odor. Didn't coat my pot or molds with solder. I don't see any reference to acid on any of the containers. I will read them again to be sure. I sure have a lot of it! I used to work in a test laboratory and it was one of the test items, tested to see if it leached any contaminants into drinking water. It didn't. They threw it into the trash along with a bunch of lead free solder..............I am not above dumpster diving for that stuff!