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OTShooter
05-09-2018, 06:14 PM
I've seen various mentions of using plain old sawdust as a very reliable flux for bullet alloy. Often these discussions include "if you don't have access to sawdust, get pet bedding." I assume that refers to the cedar bedding used for rabbits and other small pets, but there are so many different types of "small pet bedding" products that I'd be hard pressed (as a super noobie to casting) to be able to sort them out.

So first off, for fluxing, do I want "genuine wood shaving" type bedding, or will any of the paper-based beddings work? What about the pellet-type beddings, like "Eco-Straw" peleted wheat straw?

And if all of that is just details, can I use old corn cob or walnut tumbling media instead? It strikes me that they are both essentially the same as ground/shaved/sawn wood, as far as the actual purpose of sawdust for fluxing is concerned.

Of course I'm open to any suggestions or educational opportunities here. I'm here to learn.

RU shooter
05-09-2018, 07:30 PM
Just about anything carbon based will work , saw dust , straw , tree bark a simple wooded paint stir stick , dry grass clippings, paper , candle wax ect ect. I throw some old crayon in and stir with a wood stick never had a problem I certainly wouldn't go out and buy something just to flux with .

dbosman
05-09-2018, 07:30 PM
Rather than my opinion, which varies depending on what saw "dust" I have on hand, I'll refer you to http://www.lasc.us/FryxellFluxing.htm

trapper9260
05-09-2018, 08:05 PM
I use ground up corn cobs and works. I also use it for media also.

ShooterAZ
05-09-2018, 08:50 PM
Walmart has pine pet bedding, that is what I've been using. When using this type material, be very careful not to stir it into the melt until it is completely turned to charcoal. To do so otherwise is an invitation to the tinsel fairy. There WILL be some degree of moisture in the bedding.

OTShooter
05-09-2018, 08:55 PM
Mr Fryxell’s article is something I’d read thoroughly and more than once. Which is why I felt it was confusing that people suggested pet bedding, particularly without specifying what kind.

Since I have an Imperial butt-load (slightly larger than a metric butt-load) of corn cob media on hand, it looks like I’ll be OK using a little of that to flux my smelting.

On a related note, when smelting scrap (wheel weights in my case), should I flux as soon as the stuff is thoroughly melted, or wait until after stuff like the steel clips has floated to the surface and been removed?

jdfoxinc
05-09-2018, 08:55 PM
I just use the worn out walnut hull. Then wax. Any grease or fat will work. For my smelting pot mixing up large batches of 9262 I use the used fryer oil.

JSnover
05-09-2018, 09:00 PM
With bedding, corn cob, etc you can leave a layer on top as a barrier.

D Crockett
05-09-2018, 09:07 PM
OTShooter if you want to I will send you 2 blocks of flux that I use if you just pay the shipping of $7.20 give me a pm with your address and I will pm you mine D Crockett

OTShooter
05-09-2018, 09:10 PM
Mr. Crockett, that’s a nice offer, but I think I’ll try what I have first.

Gtek
05-09-2018, 09:22 PM
Large slotted spoon and get all the steel/? out. Then with solid spoon I get the whole thing swirling that make a crud pile in center, skim center off clean as I can. Cover with (I use sappy yellow pine dust) sitting until charcoal. Then stirring, swirling and scraping sides and bottom again to make spinning crud pile, clean and then pour ingots.

LAH
05-09-2018, 09:57 PM
I've used about all of it. Dry wood dust works great.

Pardini
05-09-2018, 11:46 PM
We keep a jar under the kitchen sink. Dump bacon grease etc from cooking in it. Use it to flux the smelt only, not in the casting pot. The old guy that got me started in casting used chicken fat he got from the local KFC. They used to pay to get rid of it. Now they get paid for it and keep it locked up.

Shuz
05-10-2018, 10:13 AM
When I am smelting wheel weights or other dirty alloys, I use candle wax and strike a match to the melt almost as soon as the smoke forms. This cuts down on the smoke somewhat, but it does still smoke and stink! Do this under plenty of ventilation.
Once I start casting, I use nothing but Brownell's Marvel-lux. Just a pea size amount, stir it well, and THEN COVER THE MELT WITH UNUSED KITTY LITTER. This material, which is diatamaceous earth, keeps the heat in and the air from oxidizing your melt. It has an added benefit of no smoke. Obviously this method is for bottom pouring pots only.
I have used Marvel-lux for years, and the sides of my RCBS Pro-Melt furnace remain nice and clean.

Once again, I remain the official depository for any unwanted Marvel-lux out there, and will even pay the shipping cost if the quantity justifies it!

JonB_in_Glencoe
05-10-2018, 11:33 AM
Mr Fryxell’s article is something I’d read thoroughly and more than once. Which is why I felt it was confusing that people suggested pet bedding, particularly without specifying what kind.

Since I have an Imperial butt-load (slightly larger than a metric butt-load) of corn cob media on hand, it looks like I’ll be OK using a little of that to flux my smelting.

On a related note, when smelting scrap (wheel weights in my case), should I flux as soon as the stuff is thoroughly melted, or wait until after stuff like the steel clips has floated to the surface and been removed?

First, when I use wood saw dust, I prefer "dust" from the saw. Anything with larger particles than dust take a while to burn up and turn into carbon.

When I smelt COWW, just as the alloy is fully melted or a few seconds before it's fully melted (you will quickly learn that moment), I apply a layer of saw dust ("Dust" of the saw) about 1/2" thick, then I carefully stir it in. if it doesn't ignite within a couple seconds, I will ignite it with a long BBQ lighter. Then I stir the flaming alloy/clips with a long wooden dowel or branch (24" long). In about 20 seconds, the clips should not have any trace of alloy attached to them, then you can scoop them out with a slotted spoon. If there are so many clips that you can't get them out quickly enough and alloy starts to stick on the clips again, then reapply some saw dust and repeat. OK, when all the clips are removed, I then put a bit of wax (candle or beeswax) on the melt, stir and ignite it, when it burns out, I start ladling the alloy into ingot molds.

Fluxing the Lee bottom pour casting pot:
I fill the pot with ingots, melt the alloy, stir and scrape the sides of the pot, leave some dross on the top (about 1/2"), then I sprinkle a thin layer of saw dust on the dross. Then start casting. Leaving the dross on top does a couple things. first it insulates the alloy, keeping it a more consistent temperature, it also create a oxygen barrier so the oxides don't form. Also, if you drop the sprues from the mold right back into the pot, the Dross layer floats the sprues, so they slowly melt in, and the oxides on the surface of the sprues stay on top and don't go beneath the surface and cling to the side/bottom of your pot. I only do that with pistol boolits, I prefer to leave the alloy undisturbed for rifle boolits as well as keeping the temperature much more consistent.

mdi
05-10-2018, 12:32 PM
IIRC; some wood "dust" shouldn't be used. Pressure treated wood when burned can be toxic and certain woods (cedar?) also may produce unpleasant fumes...

JonB_in_Glencoe
05-10-2018, 01:12 PM
IIRC; some wood "dust" shouldn't be used. Pressure treated wood when burned can be toxic and certain woods (cedar?) also may produce unpleasant fumes...
Yes, I agree.
I also avoid dust from plywood or other "glued" wood.

bangerjim
05-10-2018, 05:25 PM
I just use the worn out walnut hull. Then wax. Any grease or fat will work. For my smelting pot mixing up large batches of 9262 I use the used fryer oil.

Be VERY careful using vibratory cleaning media! It has a lot of heavy metals in it from your casings and you do not want to breath that garbage. Same with the other "woods" mentioned about. Avoid them. I use only good old white pine sawdust from my shop. If you don't have a power saw, go buy a pine 2x4, a hand saw and start cutting. You will have a nice pile of "flux dust" in no time. No one can use the lame excuse "I ain't got no sawdust"! And you can buy pine bedding in any pet store for a few cents.

Even dry dead leaves from you yard will work!!!!!! Any approved carbon-based material will act as a flux for your melt.

Flux-on! (now if I can just remember where I put my FLUX CAPACITOR for the car!!!!!!)

bangerjim

lightman
05-10-2018, 05:53 PM
I've always had enough projects going on to provide sawdust for my smelting operation. That is, until that last big marathon smelt that me and Biggin did together. I bought a bag of pet bedding, which was pine chips at Walmart. It seems like 5 or 10 pounds was only a couple of dollars. Worked fine but it did take a few more minutes for it to char.

Hardcast416taylor
05-11-2018, 02:49 AM
A friend of mine works at the local High School. He saves for me all the pencil sharpener contents when he empties them at the end of the day. The wood and graphite works very nice as flux.Robert

RED BEAR
05-11-2018, 09:34 AM
i use saw dust to remove impurities and parrifin wax to combine metals i set up saw to make saw dust just for this as some of the woods i use for projects are exotic and the dust can be very harmful. wenge wood dust can act like a nuro toxin when inhaled. but makes some nice grips and knife handles. if you set up a table saw or any saw for that matter it doesn't take long to have a box full.

redhawk0
05-11-2018, 09:45 AM
OK...so how much sawdust is to be used? I see "a layer on top" referenced a lot...but does that mean 1/4" or 1.5" I've only ever used candle wax but I've got almost an endless supply of sawdust. I'm willing to try alternate methods to get away from the stink of paraffin...I like the wood smoke smell. :)

redhawk

JonB_in_Glencoe
05-11-2018, 10:02 AM
OK...so how much sawdust is to be used? I see "a layer on top" referenced a lot...but does that mean 1/4" or 1.5" I've only ever used candle wax but I've got almost an endless supply of sawdust. I'm willing to try alternate methods to get away from the stink of paraffin...I like the wood smoke smell. :)

redhawk

for smelting COWW, 1/2"

when I stated this...

Fluxing the Lee bottom pour casting pot:
I fill the pot with ingots, melt the alloy, stir and scrape the sides of the pot, leave some dross on the top (about 1/2"), then I sprinkle a thin layer of saw dust on the dross.
...I'm meaning a thin layer, unmeasurable...but if you could measure it, it'd be about 1/16".
I cast inside and don't want too much smoke and my alloy is clean, so I suppose I don't need to use any sawdust, but I feel better with that little bit of carbon on the dross.

redhawk0
05-11-2018, 10:10 AM
Appreciated...I just didn't understand when I read it, I guess. Gotcha now.

Thanx....

redhawk

mdi
05-11-2018, 10:52 AM
I use a precise measurement called "1/2 handful" for my 10" diameter pot. Some things don't need to be exact; if you put "too much" sawdust (you did measure the particle size, didn't you? 14-20 works for me) it may take longer to char or burn off. If you put "too little" it may burn off quickly and not clean the melt. Most often I don't leave a layer on top of my melt, I just stir it vigorously with a paint stick and skim...

bangerjim
05-11-2018, 12:10 PM
And remember:

Sawdust is a FLUX

Wax is a REDUCER

I use both on dirty re-melts. But ONLY a pea-sized piece beeswax in my clean-ingot casting pot to get the Sn "back in". Gives you a mirror shiny surface!

banger

RED BEAR
05-11-2018, 10:55 PM
there are no exact measurements just throw enough to cover top close eather way will work. saw dust is easy to come by so just go for it not sure you could put to much.

Bazoo
05-12-2018, 02:00 AM
You should try fluxing separately with both sawdust, and with candle wax. Pet bedding means real wood bedding. While you CAN use old tumbling media, you should consider that it will have particles of metals in it, which will combine with your mix a minuscule amount. Also know as adding contaminates. \

I've found that the melt works better fluxing with wax. I use more like a marble size chunk instead of pea sized. Im not saying I dont use sawdust, nor that it dont work, but I prefer wax. I think sawdust does better when cleaning wheel weights into ingots. Helps remove the impurities.

Wax reduces the oxides back into the melt, and helps reduce the surface tension. Basically it makes it flow better.

Shuz
05-12-2018, 09:53 AM
Am I the only guy who fluxes with Marvel-lux?;-)

toallmy
05-12-2018, 12:40 PM
I just cook down the coww , scoop out the trash clips and such , and dump old motor oil in the kettle it's pretty nasty . I guess I flux with valve stems .;)

Larry Gibson
05-12-2018, 12:53 PM
I've tried about every thing to flux with over the years......including Marvel-Lux. I keep going back to simple beeswax. It is a flux BTW; so says all the od timers. The new internet experts say it isn't but it sure fluxes alloys quite well for me. I use it when smelting and when casting. When smelting I removed the clips or other non-metallic debris before fluxing. Then when smelting and casting I bring the alloy to temp (700 to 725), put a small piece (marble size) of beeswax on top then as it melts I drop 3 wooden matches on top. That burns off most of the offending smoke and odor. The alloy is stirred vigorously as described in Lyman's and other manuals and the alloy is fluxed. When smelting or if the raw material was exceptionally dirty I may repeat once or twice. The remaining debris is scraped off the top of the fluxed alloy.

murf205
05-15-2018, 09:01 AM
That is exactly how I've been doing it for a long time(40 yrs) and I although I have tried some of the suggestions I've read here, beeswax works.