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CamoWhamo
07-26-2018, 01:07 AM
Hi All,

When using Sawdust for fluxing a pot, what type of sawdust is used?

Is it the fine powder like consistency or the more coarser wood shavings.

I don't have any sawdust at home and if i asked a woodworking shop for any i'm concerned that it will be mostly from what we call MDF here in Australia which compressed wood fibres bonded with resin. What effect would the resins have?

I can get bags of organic wood shavings from a pet store. Would that work?

Thanks

David2011
07-26-2018, 01:47 AM
The pet store shavings would work. Some here have reported using it, mostly cedar shavings. Fine sawdust is better IMO as it needs to reduce to carbon dust.

You need sawdust from solid wood, though; not from MDF or plywood. We call it MDF as well and cabinet makers use it frequently. The glue in MDF and plywood would make for an unpleasant experience due to the noxious emissions. The big saws that home improvement stores cut ply with are not a good source due to the glue in the wood.

Do you have a friend that has a table or mitre saw or otherwise does woodworking? They might be able to supply good sawdust. A gallon or 4 liter bag will last a long time. It only takes a little each time but it works GREAT! Would there be a sawmill or millworks in your area? They would have good sawdust. I just use pine sawdust that I saved after some carpentry I did about 3 years ago. I save 2 gallons and can hardly tell it's been used.

Grmps
07-26-2018, 01:51 AM
The most preferable sawdust is pine due to the resin content.
no matter how good the sawdust is you still need some sort of wax (bees-wax/parafin/...) to get a complete fluxing.

Walks
07-26-2018, 02:07 AM
I just started using sawdust. I just went down to my local LOWE'S with a gallon zip lock bag & they were nice enough to fill it from the rip/crosscut Saw collector.

BOY HOWDY does that stuff make a difference. Never any more schmutz in my bullets any more.

I guess it's just a collection of mostly pine and is very uniform. Consistency of Corn Meal.

JBinMN
07-26-2018, 02:37 AM
I use mostly pine sawdust. Like was mentioned earlier, for the resin content. Occasionally I will also use beeswax, or candle wax.

Stick candles are inexpensive here & easily found. I would venture to guess that they are easily acquired in AUS., as well. Good to have around for the other uses, other than as candles when the power is out, too...

Beeswax is relatively easy to come by around this area as well since there are local apiaries, & likely would be available in AUS. as well, since you have bees there too( apiaries) { Here is some webpages to help: http://amazingbees.com.au/index.html , and for a map showing beekeepers in AUS:http://apiarymap.com/ , as well as all over the world.}

I sometimes get pure beeswax from what we call the "Dollar Store" by buying a small container of "mustache wax". https://i5.walmartimages.com/asr/961db076-181d-4210-9b69-be1640cc1dc5_1.b36520774d70ceb4ae7f1dc2a574423e.jp eg?odnHeight=450&odnWidth=450&odnBg=FFFFFF I do not use it for my mustache, but I have other uses for other hobbies/etc. & it is a small amount that is well refined & in a container already , rather than in pure, natural form. It IS from AUS. , or at least they say it is... I imagine you could fine something like that to use "in a pinch", if necessary...
;)

I also use wooden shims made of pine or cedar on occasion. I am semi retired as a carpenter/ const. contractor, so they are easily available to me. ( so is sawdust. ;) ) Either "store bought" or "home made". I also do not know if they are used in AUS., but many use "paint stirrers", to help stir the flux into the melt, and they are made of wood, so they can work as well. Wooden "shims" such as are used by carpenters to shim doors windows, cabinets, etc., should be available iif you look for them in a home improvement store or know some tradesmen in the area you are in.

Here is a link to AUS. for paint stir sticks:
http://www.unipro.com.au/products/application/uni-pro-wooden-paint-stirrer-see-bulk-buy-price-list/
https://www.unipro.com.au/wp-content/uploads/2015/01/13200-400x400.jpg

I would suggest , like was also mentioned, not to use MDF or any material that that contains anything other than "naturally" occurring components. IOW, use only natural & plain "wood", bees wax, candle wax, etc.. All the natural stuff is usually easily available & also are usually relatively inexpensive as well.

There are commercial fluxes available as well, but I do not know if they are available in AUS., nor how much they would cost there. But that is an option too...

G'Luck! with whatever your decide to use!
:)

Wayne Smith
07-26-2018, 07:57 AM
Avoid pressure treated wood sawdust as well, probably obvious but needs to be said.

I use white oak because that is what I have a lot of - and it works too.

pworley1
07-26-2018, 08:04 AM
I have a small sawmill and have used almost all the common types of sawdust. I like to use cedar because of the smell, but all types seem to work very well.

LenH
07-26-2018, 08:19 AM
My son is a keeper of reptiles and I have been getting into his bedding. He uses aspen shavings and that is what I have been using. It works just fine
for me. He moved and took the critters with him. I got a small bundle of the stuff at Walmart for a couple of bucks. It is what I started with and still use.

Hamish
07-26-2018, 08:35 AM
I found out the hard way when getting started that using sawdust is for smelting, but when it comes to actual casting a bit of old candle wax to keep it fluxed, keeps wood ash solids from getting trapped and clogging my bottom pour pot.

A lot less headaches and better bullets.

Reddirt62
07-26-2018, 09:18 AM
Another benefit of being a beekeeper...8)https://uploads.tapatalk-cdn.com/20180726/81e7facc8e732ebc39d47504d77e2276.jpg

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JonB_in_Glencoe
07-26-2018, 09:57 AM
I prefer Dust...sawdust, as opposed to wood shavings.

Recently during a smelting session (outside), I ran out of my pine sawdust.
So I run over to the local lumberyard, they only had what appeared to be from plywood and MDF...and some dust had a greenish hue. Against my better judgement, I took some, just to get me by, so I could finish up the last couple of batches of COWW. It worked just as good, but no doubt there was some bad fumes in the smoke, I stood up-wind and I ignited the smoke as soon as it would ignite.
I'm not recommending using plywood or MDF dust...just reporting that it'll work, after all, glue/resin is carbon based.

trapper9260
07-26-2018, 10:25 AM
I use ground corn cobs. I got it for nothing and also use it for my cases in the tumbler. So it all works for me.It is ground by a feed mill by a farmer some years ago.

Hannibal
07-26-2018, 10:29 AM
I found out the hard way when getting started that using sawdust is for smelting, but when it comes to actual casting a bit of old candle wax to keep it fluxed, keeps wood ash solids from getting trapped and clogging my bottom pour pot.

A lot less headaches and better bullets.

^^^^^ THIS ^^^^^

Excellent advice here.

dannyd
07-26-2018, 11:04 AM
Paint stick (wood) works great for me. Always pick up a couple when in HD or Lowes.

Poygan
07-26-2018, 11:16 AM
I also use the paint sticks exclusively.

Reddirt62
07-26-2018, 12:50 PM
Forgive my ignorance but when you say paint sticks...in what way do you use them? Thanks

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lightman
07-26-2018, 01:07 PM
I've used several different types and it seems like pine works better than the others and sawdust is better than chips. I only use these when smelting and only us wax in my casting pot. I ran out of pine sawdust recently and bought a bag of pine pet bedding at Walmart. It was fairly cheap but it was in chip form. Worked ok but took longer to char over.

lightman
07-26-2018, 01:08 PM
Forgive my ignorance but when you say paint sticks...in what way do you use them? Thanks

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You use them as stir sticks. They char over and do what sawdust does. Just to be clear, these are the wooden strips used to stir paint.

Reddirt62
07-26-2018, 01:23 PM
You use them as stir sticks. They char over and do what sawdust does. Just to be clear, these are the wooden strips used to stir paint.Thank you!

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Grmps
07-26-2018, 01:27 PM
starting with clean / smelted / well-fluxed ingots

burn/char the sawdust
https://i.imgur.com/wQVE1Hs.png

mix throughout pot with a potato masher

https://i.imgur.com/iCuL89b.png
https://i.imgur.com/hCh5CM3.png

completely incorporate with wire wisp
https://i.imgur.com/XhM9seD.png

leaves a grainy barrier on top preventing oxidation and lead from splashing when returning sprues to pot
https://i.imgur.com/PwsaaxQ.png

IF the top layer isn't completely grainy flux again with wax and it will look like grey sand

Hannibal
07-26-2018, 01:32 PM
I would advise anyone not to submerge any fluxing material into the casting pot. When reclaiming used lead from range lead, wheel weights, etc, then there is enough slag as to not matter so much. But that is a process best conducted somewhere other than in the casting pot.
My experience has been that clean lead, tin, pewter, pre-'smelted' wheel weights in whatever amounts you wish is what should go into the casting pot with a bit of wax on the top of the melt. This goes a long way toward keeping inclusions out of your cast boolits and particularly helps with keeping your bottom pour pot running clean and clog free.
Many ways to cast, but this is the most trouble free way I have found to date.

I'm not saying any one else's method is incorrect. I'm simply saying this method gives me the best boolits with the least trouble.

Hossfly
07-26-2018, 01:49 PM
I agree the pine bedding works fine except for taking longer to get to char over, also make double sure this product is dry, don’t just throw in and start stirring in. It wont take long at all to dry on top of melt be careful tho. Wear protective especially for eyes and arms, and remember everything is hot all the time.

oldlongbeard
07-26-2018, 05:09 PM
Grmps- thanks for that pictorial... they really are worth 1k words!

Greg in West Mitten

Echo
07-26-2018, 07:04 PM
I use sawdust from Lowe's, and I'm sure they saw ply as well as solid - and I don't worry about it, because the amount of bad stuff in the glue/whatever is so small that it is insignificant...

Ateam
07-26-2018, 07:57 PM
Chainsaw dust/chips works well for me, any wood variety.

kevin c
07-27-2018, 06:07 AM
I've used (clean) walnut and corn cob media, fine pine sawdust and also pine shavings from a planer. They seem much the same to me, but as a beginner, I'm not too discriminating.

One thing, though, every single paint stick I've tried started to sputter badly when put into the melt. What do you do to prevent that, dry them in an oven?

Stephen Cohen
07-27-2018, 07:26 AM
In Australia the pine shavings are available at pet stores as bird nesting material. I would never use MDF material or any material that is coloured green as it could have come from treated timber and is poisonous. I agree that some form of wax is also needed as I think it alters the surface tension and helps the rubbish float to top. I recommend using shavings from a known source as some shavings can have nasty side effects to your health. Regards Stephen

RED BEAR
07-28-2018, 11:19 PM
I just buy a cheap framing 2x4 and saw it up on table saw blade width at a time you get a lot of saw dust for two bucks. Have i been missing something I thought sawdust was for removing impurities and waxes were for combining the alloy back together ( tin etc )? I may be wrong but that is what I have always used them for.

Hannibal
07-29-2018, 12:16 AM
I just buy a cheap framing 2x4 and saw it up on table saw blade width at a time you get a lot of saw dust for two bucks. Have i been missing something I thought sawdust was for removing impurities and waxes were for combining the alloy back together ( tin etc )? I may be wrong but that is what I have always used them for.

^^^^ Winner, Winner, Chicken Dinner ^^^^^^^

EDG
07-29-2018, 12:48 AM
When I have a piece od scrap pine that is saturated with sap I turn it into sawdust.

Stephen Cohen
07-29-2018, 04:36 AM
I just buy a cheap framing 2x4 and saw it up on table saw blade width at a time you get a lot of saw dust for two bucks. Have i been missing something I thought sawdust was for removing impurities and waxes were for combining the alloy back together ( tin etc )? I may be wrong but that is what I have always used them for.

I agree with you 100%. Regards Stephen

ricwb
07-29-2018, 05:24 PM
In our school shop, white pine and oak are the two most used woods. A few scoops taken from under the table saw will last a very long time. I always cast outdoors, so the smoke and smell is no problem. If any of the sawdust is from plywood, it never has caused any problems.

jsizemore
07-29-2018, 08:20 PM
I got a fella in my area that has a home sawmill. He cuts plenty of wood and is happy for anybody to take as much as they can haul off his hands. You got to shovel your own saw dust though. I load the wheelbarrow up and haul it to the pile in appreciation. I'll pull slabs and stick lumber while he cuts too.

At times he'll impart a bit of wisdom. He told me that Abe Lincoln said you could believe anything you read on the internet.