pine shavings vs sawdust for flux

[openbook]

I've heard that sawdust first then beeswax is even better. Tried it yesterday and it worked far better than just beeswax. Smooth, shiny wheel weight boolits in 9mm. Didn't have trouble from the plywood glue either. I'm guessing the glue isn't much worse than burning paint off the old wheel weights.

[mto7464]

old candles work well too. get a nice flame once it gets hot enough or I hit it with the lighter and some of them smell good too. I do cast outside. No need to ever buy anything to flux. even have used dried leaves that blow under my outside area. Plus the wax keeps the hinge on my pot well lubed (that is what I rub the candle on to get it to melt and go into the pot).

[GregLaROCHE]

I’ve used everything thing from sawdust to straw to Quaker Oats. They all worked. Just make sure whatever you use is completely dry.

[Chaparral66]

Ok, I'm going to go out on a limb here. I've been in the electronics industry for 50 years. We only use flux to assist in getting a good solder joint. In our wave solder machines there is no flux used in the solder pot and even after years of operation the alloy remains almost exactly what was in the pot initially.

Fluxing a smelting pot or a casting pot to "keep the alloys mixed together" if a fallacy. I defy you to remove any one unique metal from the alloy by any means. In a post I read last night it was stated that "tin will separate out hence the need of fluxing" is an old wives tale.

I do not flux. I do gently "scrape" off the crap (dross) on the top of the molten alloy.

If you are using saw dust or chips it will not f-up your bottom pour pot. Now you say yes it will. Ok, think of this, when smelting range scrap, COWW, roofing flashing or any matter of raw material what floats to the surface... everything that is lighter than lead. So the zinc, steel, wood chips, dirt (sand from range berm) or any other lither than lead material is going to be part of the crap floating on the top of the molten lead or alloy.

So what we have been doing for the last ? years is BS! Prove to me that it makes a difference. I'm an engineer and I believe in hard data to show the truth. Has anyone done a DoE (Design of Experiment) to compare fluxed and unfluxed alloy to see if there is any difference?

Ok, now the heckling may begin.

[imashooter2]

What we call fluxing is reducing oxides back into the melt. The same way as what we call smelting isn’t really.

You choose to scrape off those oxides and throw them away. Enjoy!

[JohnH]

Ok, I'm going to go out on a limb here. I've been in the electronics industry for 50 years. We only use flux to assist in getting a good solder joint. In our wave solder machines there is no flux used in the solder pot and even after years of operation the alloy remains almost exactly what was in the pot initially.

Fluxing a smelting pot or a casting pot to "keep the alloys mixed together" if a fallacy. I defy you to remove any one unique metal from the alloy by any means. In a post I read last night it was stated that "tin will separate out hence the need of fluxing" is an old wives tale.

I do not flux. I do gently "scrape" off the crap (dross) on the top of the molten alloy.

If you are using saw dust or chips it will not f-up your bottom pour pot. Now you say yes it will. Ok, think of this, when smelting range scrap, COWW, roofing flashing or any matter of raw material what floats to the surface... everything that is lighter than lead. So the zinc, steel, wood chips, dirt (sand from range berm) or any other lither than lead material is going to be part of the crap floating on the top of the molten lead or alloy.

So what we have been doing for the last ? years is BS! Prove to me that it makes a difference. I'm an engineer and I believe in hard data to show the truth. Has anyone done a DoE (Design of Experiment) to compare fluxed and unfluxed alloy to see if there is any difference?

Ok, now the heckling may begin.

Dennis Marshall agrees on the separation thing. His knowledge on the subject can be found in Lymans Cast Bullet Handbook #3

[jeepyj]

Ok, I'm going to go out on a limb here. I've been in the electronics industry for 50 years. We only use flux to assist in getting a good solder joint. In our wave solder machines there is no flux used in the solder pot and even after years of operation the alloy remains almost exactly what was in the pot initially.

Fluxing a smelting pot or a casting pot to "keep the alloys mixed together" if a fallacy. I defy you to remove any one unique metal from the alloy by any means. In a post I read last night it was stated that "tin will separate out hence the need of fluxing" is an old wives tale.

I do not flux. I do gently "scrape" off the crap (dross) on the top of the molten alloy.

If you are using saw dust or chips it will not f-up your bottom pour pot. Now you say yes it will. Ok, think of this, when smelting range scrap, COWW, roofing flashing or any matter of raw material what floats to the surface... everything that is lighter than lead. So the zinc, steel, wood chips, dirt (sand from range berm) or any other lither than lead material is going to be part of the crap floating on the top of the molten lead or alloy.

So what we have been doing for the last ? years is BS! Prove to me that it makes a difference. I'm an engineer and I believe in hard data to show the truth. Has anyone done a DoE (Design of Experiment) to compare fluxed and unfluxed alloy to see if there is any difference?

Ok, now the heckling may begin.

This is getting interesting. Not sure is I completely agree but I know I don't completely disagree. Continuing to follow.

[bangerjim]

The only difference I see in fluxed and unfluxed is the unfluxed ingots can (not always) have lots of inclusions of garbage in it. Cut/slice some ingots apart and you will find garbage in the unfluxed ones. It appears to be the foam & crud on top of the melt. That is why when I re-melt dirty old carp, I 3x flux with wood and then finish off with bees wax.

And I ALWAYS use bees wax as a "reducer" for the Sn during casting sessions to keep the Sn in the alloy.

The term "flux" as we use it on here is totally different than the term "flux" used to solder copper or metals together and to get the bonding materials to stick to each surface, as in sweating copper plumbing or soldering connections the electronics industry.

Proof enough for you.......from one engineer to another?????????????????


banger