Fluxing with sawdust

[MrNRA]

I am reading the boolit casting book by Glen Fryxell & Robert Applegate and they suggest stirring in a tablespoon of sawdust for "fluxing" the melt. Has anyone tried this? What type of sawdust; pine, maple, walnut or doesn't it matter? I am a couple of weeks from casting and am reading as much as I can. Thanks for any suggestions.

Jeffrey AKA MrNRA

[huntrick64]

Quite a bit of info in older threads on this. Sawdust is ALL I use. Lately I use the large dust / small cuttings from my jointer. This is from Osage Orange and works better than anything else I have tried. I used to just stop by the cabinet shop and get whatever they sweep up, but the last time I jointed Osage, I kept it for this purpose and it works awesome. One warning, if it is a little dry and windy, and your casting outside, the alloy will ignite the sawdust and the wind will blow it our of your pot and into the dry grass. Don't ask!

Also, since your new to this, if you have a bottom pour pot, just leave the burnt sawdust on top of your alloy the whole time your casting and it will serve as a barrier to limit oxidation. Sometimes if the fluxing brings **** to the top of my melt, I will skim it off and reflux with sawdust, then leave that second flux on top while I cast.

[blikseme300]

Any sawdust, as long as it is dry, is good. I use wood shavings that is used for pet bedding that my local farm and ranch supplier sells.55407


Bliksem
Sent from my iPad using Tapatalk

[cbrick]

Welcome to CastBoolits MrNRA,

Anyone here tried sawdust? :mrgreen: A huge number of folks here use sawdust exclusively me included due in no small part to Mr Fryxell. A very wise decision on your part to read "From Ingot To Target" as your getting started, a huge amount of info in it's pages that will get you going in the right direction. Next to that book is this forum right here, another wise decision on your part in joining. There is literally many hundreds of years collectively of casting experience here. Most of the members are quite willing to help new casters and share their experience. As you start casting remember . . . The only stupid question is the one you don't ask.

Good luck,

Rick

[9.3X62AL]

+1 to all the above info, esp. the WELCOME ABOARD part! I am another who uses sawdust as fluxing agent, both for smelting and pre-cast "confirmation cleaning" of the smelted metal.

[sundog]

Sawdust works very well. I am currently working my way through a bucket of seasoned elm chain saw chips and shreds. Another thing that works very well is ash from the wood stove. Ashes left on the surface of the final casting melt make a good protective layer.

[gunoil]

hard wood shavings, ditto huntrick

[MBTcustom]

I use sawdust exclusively.
Read Fryxell's article.

[Jim Flinchbaugh]

we have a large bin, that catches the shavings from our surface planer.
When we change the oil in our vehicles, it gets dumped into the bin and stirred up.
It makes great fire starter- no kindling required and while it stinks, it makes great a
reductant for "fluxing" and putting the tin back in the mix. The other day I dumped some used cooking
oil in the bin. When I fluxed, it smelled like french fries cooking :mrgreen:

[Grandpas50AE]

I also would like to welcome you aboard. After many years of trying different fluxing materials, I have gone to exclusively sawdust. It seems to work better than anything else, and doesn't muck up the pot. The "From Ingot to Target" is one of the best boolit casting reference books you could possibly read. And like cbrick said, this web site has the very best base of knowledge and experience for boolit casting of any website, and the folks here are really the best folks of any online community I've seen.

Welcome again to the world of boolit casting. If you ever hunt and take a game animal with one of your cast boolits, you'll probably be hooked on hunting with cast except under the most extreme of circumstances. Good luck.

[mdi]

Welcome to the addiction. I, too, use sawdust for fluxing my melt. I emptied the dust catcher of my miter saw and needed something to flux with and noticed a bag of "Smoke Chips" by my BBQ and tried that. Works good plus a good hickory smell to the casting room...

[Charlie Two Tracks]

I also use sawdust. Make sure you let it sit on top of the lead for awhile to let it dry out. Even packaged sawdust has moisture in it. If you start to stir in the sawdust and see or hear bubbles................ STOP and let it dry out. Just putting a cold spoon into molten lead can cause it to erupt. Try searching for
" The tinsel fairy" on this site. You will find out what I'm talking about. 700-800 degree lead can and will burn deep and quick. You just have to do some reading and asking around here before you do something you wish you had not done. A guy has just got to be careful.

[prs]

When I started using saw dust soon after I started having clogged bottom pour outlet. But, maybe a coincidence or maybe more related to the wooden pot scraper I fashioned. I am back to a metal spatula and bee's wax.

prs

[trixter]

MrNRA: Welcome. I too use sawdust, living in 'timber country' I have a friend that goes into the mill where they cut pine lumber, and he gathers up a coffee can full about once a month. The last time he brought me wet, and I just spread it out on a couple of "DollarTree" tinfoil cookie sheets and let it dry for about a week. I have found that Ponderosa Pine sawdust works the best for me, the resins in it do wonders in the melt. I too stir them in very well then light them and let the charcoal sit on top of the melt. Happy casting!

[**oneshot**]

all sawdust except pressure treated from my saw becomes flux. I have a catch bucket to gather it up. I usually do a mix of mostly pine with various hardwoods in it too.

[fredj338]

I've used a lot of things to flux but sawdust is by far the best. Just don't use MDF or even plywood, no way to know if the chemicals hitting 800deg lead is going to cause fumes of some kind. I only flux during ingot casting & when casting bullets, I use a wooden paint stick to stir w// That seems enough to keep things running smoothly.

[gray wolf]

I use the pine animal bedding, a 5$ bag will last a mighty long time.
I like the extra added resin from the pine, ( rosin )

[40Super]

I use 2x4s and cut them up with a course blade on my miter saw. I also get a few 3 to 4 inch pine logs(red and white pine locally) to saw up into chips. Works the best that I've tried. If you use it in your bottom pour( a person shouldn't, but if you don't have anything else to smelt in) , it can get ash under the lead at the bottom and clog up the spout. I have a scraper that I constantly am scraping the bottom starting at the spout and scrape away to the edge and then up the side. This gets most of it out and keeps the spout generally clean. I just empty the pot more often to get it all out.

[Dan Cash]

Sawdust does a fine job of fluxing. Trouble is as noted by 40Super, ash and small carbon particles get trapped in the melt and don't always rise to the top. He has trouble with a bottom pour, I am a dipper/ladle man and find ash inclusions in my bullets regardless how carefully I skim after fluxing. I prefer a cooking oil and Canola is the best of them. It has a very high flash point so it won't flame up into your face like parafin and some other oils. It works for me.

[cbrick]

I must be doing something wrong. :veryconfu

Sawdust is all I use and not once have I had inclusions or anything in the spout.

The only thing I can think of is that I need to start stirring with a wood stick. That evil stainless spoon must be the culprit. :shock:

Rick

[olaf455]

I believe the trick is to allow all sawdust to turn white prior to stiring it in, this seems to keep the ash from combining with the melt and remaining below the surface. It also all but guarantees you will not get any moisture into the melt. stir thoroughly and then I skim it of the top. I prefer a pea size amount of paraffin placed on top of the hot melt as a barrier for oxidation. Drop it in and it will instantly melt seek its own level and the excess will flame up and burn off.
I do not stir the ash in to the melt very deep, I tend to stir it about halfway into the melt and constantly bring the melted alloy from the bottom of the pot to the top with my steelse spoon.
This seems to work very well.

Sent from a cold damp basement near you.

[cbrick]

I see, now I know what I'm doing wrong. :mrgreen:

I don't try to get any of the sawdust (or ash) under the melt cause that would give you inclusions and could even get into the spout. I always stir from the bottom up and bring as much of the alloy up to the carbon on top of the melt as possible.

Rick

[SgtDog0311]

Stopped by to see my nephew's shop he's standing up. Came away with two trashbags of Walnut shavings from a planer. Glad I had read some of the comments here on sawdust or it would have gone in the trash bin. John

[gandydancer]

I am reading the boolit casting book by Glen Fryxell & Robert Applegate and they suggest stirring in a tablespoon of sawdust for "fluxing" the melt. Has anyone tried this? What type of sawdust; pine, maple, walnut or doesn't it matter? I am a couple of weeks from casting and am reading as much as I can. Thanks for any suggestions.

Jeffrey AKA MrNRA Clean sawdust is great. as long as there is no glue used in the wood. And also stay away from "cedar" it has oil in it. I tried it and was sick for two days. Burning ceder works great for keeping bugs away. That has to tell you something. GD [smilie=s:


you are all right. cedar just don't like me. my son use's it for fluxing with no trouble. I will stick with pine sawdust. GD

[doctorggg]

I use the pine pet bedding material from Wally World. It seems there are many ways to use sawdust from the above posts. I don't have ready access to sawdust therfore the pine pet bedding material. I haven't had any inclusions or clogging of the nozzle on my RCBS Pro Melt. I'm not sure what I'm doing right but it works for me. Welcome to this forum. Like what has been previously said there are many years of experience here and the people are the greatest and willing to help newbies like you and me. I read Fryxell's book and it is great.

[Mlcompound]

I have used sawdust from a 2x4 and my miter saw and it works great. No problems with the spout yet but I will make sure to stir from the bottom up now.

Sent from my Nexus 7 using Tapatalk 2

[res45]

Another sawdust user here,I leave the char on top especially if I'm running the pot temp one the hot side.

[geargnasher]

I see, now I know what I'm doing wrong. :mrgreen:

I don't try to get any of the sawdust (or ash) under the melt cause that would give you inclusions and could even get into the spout. I always stir from the bottom up and bring as much of the alloy up to the carbon on top of the melt as possible.

Rick

+1, technique is key here. Drawing up metal from the bottom and pouring it through the charring layer of sawdust exposes as much metal as possible to the sawdust so it can "absorb" impurities. Just letting it sit on top has the benefit of creating the reduction/oxidation reaction which reduces the oxidized, tin-rich "dross" or "scum" layer back into the melt again, but it can't truly "flux" (remove impurities like aluminum, iron, calcium, zinc, etc.) unless the metal containing such impurities is thoroughly exposed to the chemical action of the burning sawdust.

Fryxell's article The "simple" act of fluxing on the LASC site is also an excellent read and companion piece to the chapter in the FITT book.

Some notes from my own experience: Don't use sawdust generated from plywood, OSB, particle board, or anything containing formaldehyde glue, it makes nasty, poisonous fumes that are difficult to fully evacuate with most casting setups, even outdoors. Stay clear of pressure-treated lumber (the green stuff) for the same reason. Some woods, such as Western Cedar and similar aromatic cedars, walnut, and a few rare exotic hardwoods release some chemicals that cause a bad reaction for some people. One member here in particular has made himself very ill on a few occasions trying different woods for flux and finally gave up entirely due to his extreme sensitivity to wood smoke.

I've run the gambit, being a hobby woodworker and having a neighbor as a professional cabinet/furniture builder, and have settled on Yellow Pine shavings/chips/sawdust, the more sticky rosin/sap it has, the better. Pine rosin "supercharges" the combustion/reduction/oxidation reaction by boosting the aromatic hydrocarbon content and catalyzing the reaction. It smells good, and the smoke/fumes are easy to light off with a BBQ lighter to virtually eliminate soot/smoke. Another member here suggests making shavings from a 2x4 scrap [I'll reiterate Yellow Pine is better than fir or "whitewood"], electric drill, and a paddle bit if you don't have easy access to pre-made, clean sawdust or shavings (foreign concept to me, but surprisingly common apparently!)

Gear

[Sax.45]

I'm new to casting, trying to learn as much as I can from the good folks on this forum. Went to Wally World yesterday and bought pine bedding in the critter section.

Funny thing is at my previous job I was a carpenter in a factory, Had to build shipping boxes and crates. Every few days I emptied the collection bags and chucked all the sawdust into dumpsters. I dumped tons of the stuff. Now I have to buy it at Wally World....:cry:

Sax.45

[cbrick]

Funny thing is at my previous job I was a carpenter in a factory, Had to build shipping boxes and crates. Every few days I emptied the collection bags and chucked all the sawdust into dumpsters. I dumped tons of the stuff. Now I have to buy it at Wally World....:cry: Sax.45

Yeah, nobody ever said the world is fair. :mrgreen:

Rick

[geargnasher]

This is why I'm such a packrat. I save all sorts of garbage as long as it's free, and sooner or later I almost always find a use for whatever it is. Still trying to figure out what to do with the two garbage bags of packing peanuts collecting dust in the attic, though. The two, 55-gallon drums of fine, plywood sawdust I collected working at a cabinet shop years ago are no good for flux, but excellent for containing oil spills and one day might become filler for a boolit trap if I get time to build one.

Gear

[prs]

Agree with Gear, the place to vigorously flux with the intent of cleaning the alloy is in the rendering pot. If you prepare the alloy well, the need for fluxing is to reduce oxidized tin back into soluble tin.

prs

[cbrick]

Agree with Gear, the place to vigorously flux with the intent of cleaning the alloy is in the rendering pot. If you prepare the alloy well, the need for fluxing is to reduce oxidized tin back into soluble tin. prs

Except . . .

I also try to get the alloy as clean as practicle while smelting the alloy and making ingots. It isn't logical to think that when doing the smelting that you got out everything that could possibly be in the alloy that you don't want in the alloy. I not only flux vigorously when casting to reduce the tin but also to get the alloy a bit cleaner. Every time I heat up the casting pot I flux with sawdust to clean the alloy, when I add those "clean" ingots to the casting pot I flux with sawdust. Vigorously.

Rick

[geargnasher]

I also like to leave the ash layer on top after fluxing my bottom-pour. This helps clean the sides of the pot as the level drops, and seals the top of the melt from oxygen and thus prevents the loss of tin through dross formation.

Gear

[milprileb]

This sawdust flux has made my casting life significantly better. I do leave the ash on top of the melt as Gear mentions. My pot is clean and my alloy is as well. Thanks to Gear and the guys for promoting this flux.

[Cadillo]

I bought a bag of compacted cedar wood chips at PetSmart. Unlike others, I have found nothing offensive about the use of cedar as opposed to other wood types. When I opened that bag, the contents expanded immensely. I think I have enough to fill three large metal trash cans, which should last me many years. These chip are are coarsely ground, which makes skimming the resultant ash a lot quicker and easier.

I've tried just about everything for flux, and sawdust beats all the others hand down!

[Cadillo]

Clean sawdust is great. as long as there is no glue used in the wood. And also stay away from "ceder" it has oil in it. I tried it and was sick for two days. Burning ceder works great for keeping bugs away. That has to tell you something. GD [smilie=s:

Cedar wood itself is good for keeping bugs at bay. In the old days, closets were lined with cedar to keep the moths out of things. The house I grew up in had five cedar lined closets. That's also why Grandma's old chest where she stored the wool blankets was made of cedar. I flux with coarsely ground cedar bedding chips, and find the smell to be plesant. Best flux I've tried.

You must have an allergy to it. I react badly to WD-40 and Kroil. Everyone is different.

[rr2241tx]

Any sawdust, as long as it is dry, is good. I use wood shavings that is used for pet bedding that my local farm and ranch supplier sells.55407


Bliksem
Sent from my iPad using Tapatalk

That's exactly what I use now. I ran out of my own sawdust and had resorted to cedar bark which was flaming up pretty good and creating quite a smell. About dusk, a neighbor came rushing over to see if I was OK because he saw the flames through the trees and thought I'd caught the house on fire. No more cedar bark fluxing for me.

[blackthorn]

Some people have a predisposition to developing a reaction to the poisions (that make for a good bug repellant) contained in Cedar! Not all of us are so unfortunate. I have dealt with workers with Cedar induced Asthma from inhaling Cedar dust and also I have known workers (loggers) who developed skin problems from working in Cedar swamps caused by the Cedar poisions leeching into the water. Other wood types can also cause problems for those among us with a predisposition.