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Bo1
01-12-2013, 07:28 PM
Can the wax used for flux be a scented candle, or does it have to be pure?
Thanks,
Bo

semtav
01-12-2013, 07:51 PM
You'll just have to experiment to see what works best. I had a white candle that put the dross back in great and a purple candle that didn't. both were scented

runfiverun
01-12-2013, 08:29 PM
if it melts and burns it will reduce oxides you need the oxygen free barrier [carbon monoxide] for this to happen.
it doesn't carbourize the alloy though.

HiVelocity
01-12-2013, 08:42 PM
Sawdust, plain simple free, sawdust.

Its what you'll end up using eventually anyway. (I think we all pretty much ran the gamut of trying what we think works! Lol!)

HV

chevyiron420
01-13-2013, 01:45 AM
Every year after Halloween the store my wife works at has a bunch of those wax lips left over. Man they work great for flux.

lwknight
01-13-2013, 02:01 AM
There are different chemistries of wax/paraffin. Some melt and burn at lower temperatures than others.
The scent has nothing to do with what wax is used but rather the quality of the wax. I think that generally
cheap candles have lower quality wax and are best for our fluxing purpose.

Cheap wax is sooty and harder to burn which is perfect for us. High quality wax burns off clean and at lower temperatures so its not so great for reducing oxides and releasing garbage from the alloy to be skimmed off.

geargnasher
01-13-2013, 02:39 AM
WAX IS NOT A FLUX. Grease/oil/wax is a sacrificial reducant, meaning that as it burns it creates a reduction/oxidation reaction on the melt's surface that un-oxidizes the oxide scum that forms on top so that the metal, particularly tin oxide, isn't lost by skimming and throwing it away.

Fluxes remove things us boolit casters consider impurities from the alloy while leaving behind the things we want to keep. Things we want rid of that impede the flow qualities of the metal are zinc, calcium, aluminum, iron, copper (depends), and pretty much any other trace junk metals. Things we want to keep are antimony, tin, arsenic and maybe trace bismuth and sulfur.

Plain, pine sawdust or wood shavings do all of the above if allowed to smolder to ash on top of the melt and if the melt is stirred gently to expose as much of the molten metal as possible to the carbohydrates in the sawdust.

Gear

williamwaco
01-15-2013, 09:56 PM
Can the wax used for flux be a scented candle, or does it have to be pure?
Thanks,
Bo

Any scrap candle is fine, as is paraffin from the super market.
Or used crayolas from your kids, or any other wax.

That said, I fluxed that way for 50 years until I joined this forum and was perfectly happy.

I learned here that sawdust does a better job and it is also free.

.

soli
01-15-2013, 10:23 PM
Does it matter what type of sawdust[soft or hard wood]?

geargnasher
01-15-2013, 10:25 PM
Wax is not a flux.

Wax is not a flux.

Wax is not a flux.

Wax is not a flux.

Wax is not a flux........

:bigsmyl2:

Gear

geargnasher
01-15-2013, 10:29 PM
Does it matter what type of sawdust[soft or hard wood]?

Not really. Having a friend nearby who owns a custom cabinet and wood working shop I've tried lots of different things, and my current favorite (for some time) is yellow pine sawdust, the sticky, resiney stuff. The resin seems to help speed the reduction of oxides and remove oxide scum from the sides of the casting pot (as you would normally use some sort of wax to do) compared to drier woods like walnut, maple, alder, pecan, hickory, oak, etc.

Gear

Bullshop
01-15-2013, 10:44 PM
True wax is not flux by itself but when combined with sawdust or other material that will produce carbon and ignited you have a very good flux.
The carbon from the burning sawdust and the heat from the burning wax will greatly help reduce slag back into the melt and it is also very helpfull when alloying for the same reasons.
That has been my experiance.
BTW tallow works as well as wax.

geargnasher
01-15-2013, 10:47 PM
Any hydrocarbon can reduce oxides (the reduction part of the reduction/oxidation chemical reaction) through combustion and oxygen exchange.

Removing impurities from boolit metal requires something different, like carbohydrates or borates that absorb and isolate impurities from the melt so they can be skimmed away.

Gear

leadman
01-15-2013, 10:57 PM
I use old candles all the time for flux with no issues. Beeswax also works very well but leaves a residue on the pot. I work it thru the alloy with a large spoon. Sawdust also works as long as it is not from particle board or osb.

Wolfer
01-15-2013, 11:01 PM
I've used beeswax, parrifin, different candles, crayons, a pine stick and sawdust.
I suggest you try the sawdust last or you may not get to try the others.

Bo1
01-15-2013, 11:22 PM
Well I cast my first ingots this past weekend, and to play it safe, I put pine sawdust several times, and then put wax after skimming off the burnt sawdust. Hope that was right. :0)
Also my wife tout I was nuts cutting little slivers off of a 2x4 with my circular saw in the shop trying to get the sawdust.

geargnasher
01-16-2013, 12:14 AM
Wax does not flux, really, it doesn't. It reverts oxidized metal to its elemental state, but it does not FLUX.

Gear

leadman
01-16-2013, 02:54 AM
Well, whatever it does it gets the junk out of the lead and the metal scum that was on the top disappears into the melt.

blikseme300
01-16-2013, 04:59 AM
I've used beeswax, parrifin, different candles, crayons, a pine stick and sawdust.
I suggest you try the sawdust last or you may not get to try the others.

Well put. I tried all kinds of things before I tried sawdust. Never looked back...

Willbird
01-16-2013, 09:39 AM
I have used ground corncob too when it was handy.

Bill

dverna
01-19-2013, 07:53 PM
I think Gear is on a mission - but few are listening - LOL

Don

Wolfer
01-19-2013, 08:39 PM
I think Gear is on a mission - but few are listening - LOL

Don

Don't get depressed gear, I'm listening!

lwknight
01-20-2013, 04:18 PM
OK , I admit that in the true sense of the word " wax is not a flux" is basically a true statement but if you want to get technical , nothing is a flux.
In fact the word "flux" literally means " flow" as in luminus flux means flow of light.
What about plumbius flux ? Flow of lead right?
Some things are fluxing agents or aka catalists for a reaction.

EG: Zinc-cloride is a great fluxing agent/catalist for fusing tin to copper with a deep intermetallic bond.
Just get some wax on your copper and you will not be soldering anything in that area.

But still the redneck flux like wax , motor oil , june bugs , cow manure or wood chips all help reduce oxides and release foreign materials from our alloy.

Bullshop
01-20-2013, 05:06 PM
OK OK so wax is technicly not a flux but a reducing adjent but isnt that what we are looking for?
So since adding tin makes lead flow in a more fluid fashon would you call tin a flux?
I think maybe the word FLUX has more than one meaning and we are applying it in a wrong way.
Our purpose is not the same as that in the bonding of metals as in soldering, brazing, welding.
Our purpose is to not have it stick to anything pot, ladel, mold, or barrel.
This I do know when I flux or what ever word I should use for what I do to clean my melt and to reduce as much slag back into the melt as possible so there is as little wast as possible that which I do with burning wax and sawdust works for my purpose perty dan good no matter what its called.

LtFrankDrebbin
01-20-2013, 07:00 PM
How bout borax? Worked for blacksmiths and forge welding for a "little" while :mrgreen:

Bullshop
01-20-2013, 08:59 PM
That was my point were not trying to weld or solder just the oposite we want to avoid bonding.
Flux the word must have a dual meaning. Flux a copper pipe to get solder to stick but flux a pot of boolit alloy to render the dross and help clean it.

geargnasher
01-20-2013, 10:42 PM
Flux means to flow. In metallurgical terms, or rather foundry terms, "flux" means to remove the impurities that prevent the quality flow of metal. Tin, actually, could be considered a flux because its surface oxide barrier characteristics in a lead alloy tends to allow the metal to act as if it has a lower surface tension, and thus "flow" better.

Most of the contaminants I've listed over and over again impede the casting quality of boolit alloy. Wheel weights are rife with calcium and aluminum these days, and both of those metals cause clumping and "gritty" alloy. Many people want to just dump in a pile of tin or crank the heat up all the way to try to make their scrap metal cast better, but a lot of the time I suspect it's the high content of impurities that is really causing the problem. "What do you mean, I "fluxed" three times with candle wax, my alloy is clean!" an astonished caster might say. Well, maybe not so much, because your wax didn't do what you thought it was supposed to.

See why I harp on the difference? Oxide reduction and contaminant removal are two completely different things, and if you use dirty/unknown scrap (that means wheel weights especially, and roofing metal, plumbing lead, battery cable ends, old sinkers, etc.) you especially could benefit from FLUXING with a borate or something like SAWDUST.

Gear

Cadillo
01-21-2013, 12:20 AM
I've tried every known commercial fluxing product, as well as parafin, wax, crayons, Crisco, motor oil, etc. Sawdust is now the only thing I use. Keeps my melt and pot CLEAN, and occasional re-fluxing keeps the surface oxides in check. No stinky black smoke or blazing flareups.

Cheap to free and easy to come by. I will never again use anything else.

LtFrankDrebbin
01-21-2013, 06:09 AM
Is there a sticky on this topic? I reckon it would have to be one of those questions that keeps popping up and for you long time casters you'd feel like broken records.
I am a fabricator welder by trade- fluxing, oxidization and the surounding apmosphere are things I understand all too well from a practical side.
Gifted at putting all this into words or theory I am not!
Is a sticky a possibillity here about fluxing, charactoristis of usable material for removal of impurities, then fluxing.
A few pictures of coarse for us hands on type :-D

milrifle
01-21-2013, 11:06 AM
Do you guys use sawdust while casting indoors? I tried it once and smoked up the whole shop. What's worse, what was left in there stunk to high Heaven. Smelled like someone burning leaves. I couldn't stand it. I scooped it out and swore I would never try it again. 'Course that was before I found out just how common a practice this is, so i figure I must have goofed it up somehow. Easy enough for a newbie like me. Too hot? Used too much? Not enough? Something? What did I do wrong? Are there some step by step instructions?

DeanWinchester
01-21-2013, 12:35 PM
I started using cedar shavings. I use them in the dog house so I always have them around. They sure make the shop smell nice and do a good job of making the alloy clean as well.

I'm thinking I might try some hickory or pecan wood. I know a guy who cuts it for the local BBQ joint so I could get a bucket of chainsaw dust for free. I bet mesquite lead would smell nice!

cbrick
01-21-2013, 01:43 PM
Removing impurities from boolit metal requires something different, like carbohydrates or borates that absorb and isolate impurities from the melt so they can be skimmed away. Gear

I would leave the borates out of this. Yes, it does remove the impurities AND the tin, arsenic and anything else. And that says nothing about how horribly it gunks up your pot & tools.


Well, whatever it does it gets the junk out of the lead and the metal scum that was on the top disappears into the melt.

No, actually that is chemically impossible. Wax does not, cannot remove the impurities. Yes, it will reduce tin and the things you want removed right back into the melt.


Sawdust also works as long as it is not from particle board or osb.

Particle board and/or OSB does work just fine but it introduces some nasty smoke that you really don't want to breath. Same with plywood because of the glue, it works fine but don't breath the smoke.


In fact the word "flux" literally means " flow" as in luminus flux means flow of light.
What about plumbius flux ? Flow of lead right?
Some things are fluxing agents or aka catalists for a reaction.

EG: Zinc-cloride is a great fluxing agent/catalist for fusing tin to copper with a deep intermetallic bond.
Just get some wax on your copper and you will not be soldering anything in that area.

Not correct! We are not welding here. As Gear explained the terminology for a welder is different than it is in the metals industry and foundry's. Fluxing a melt is to remove impurities from the alloy, fluxing while soldering or welding is to remove oxidation (and oxygen) from the metals surface so the parts can join.


So since adding tin makes lead flow in a more fluid fashon would you call tin a flux?

NO! Tin is not a flux, tin works by reducing the surface tension of the alloy entering your mold. Tin looses most of it's ability to do this past 750 degrees and also tin itself oxidizes much faster when heated past this temp. If tin where a flux it would remove impurities, it does not.

Rick

geargnasher
01-21-2013, 03:10 PM
Agree 100% on the borates, nasty stuff I won't use, but it DOES flux well. BTW, it only removes tin in oxide form, so if you reduce the oxides first, then apply the borate and stir well, it can remove the other junk pretty well. Sawdust is still a million times better, though.

Gear

lwknight
01-21-2013, 08:07 PM
One thing that I can say in defense of wax is that it will help release fine particles of impurities in the alloy that are not part of the alloy. You always get dust and even sand trapped beneath the surface that cannot break t he surface tension to break out.
After waxing , a goodly bit of dust/powders will be left on top for skimming. Sometimes you can even see grains of stuff trying to float out and waxing will allow it.

pt4u2nv
01-21-2013, 09:38 PM
Do you guys use sawdust while casting indoors? I tried it once and smoked up the whole shop. What's worse, what was left in there stunk to high Heaven. Smelled like someone burning leaves. I couldn't stand it. I scooped it out and swore I would never try it again. 'Course that was before I found out just how common a practice this is, so i figure I must have goofed it up somehow. Easy enough for a newbie like me. Too hot? Used too much? Not enough? Something? What did I do wrong? Are there some step by step instructions?

Take a lighter or match and light the sawdust just as it starts to smoke. It will ignite and no more smoke . You will be left with a coating of burnt wood ashes that you can flux into the melt.

44man
01-22-2013, 09:50 AM
Now fellas, don't you remember when I was playing around with boolit lubes? I got out a hunk of brass and my soldering iron. I used every lube from BP to all the the other lubes I have. Every one let me solder just fine.
I was watching a lead smelting and casting operation on the history channel last week, huge pot of lead. They tossed in WAX!

Mal Paso
01-22-2013, 10:09 AM
One thing that I can say in defense of wax is that it will help release fine particles of impurities in the alloy that are not part of the alloy. You always get dust and even sand trapped beneath the surface that cannot break t he surface tension to break out.
After waxing , a goodly bit of dust/powders will be left on top for skimming. Sometimes you can even see grains of stuff trying to float out and waxing will allow it.

I noticed that but didn't know why.

I "flux" when "smelting" and again when blending the Alloy with Cedar Sawdust but only Beeswax goes into the casting pot.

sig2009
01-22-2013, 10:18 AM
Candle wax is more readily available so that is what I use.

Friends call me Pac
01-31-2013, 11:13 AM
I've been using candle wax to flux for years while pouring my lead fishing baits. I just started casting my own boolits & never heard of using sawdust before. I'll certainly try it out. Now it's off for more handy tips.