Used walnut cleaning media for flux?

[S A Webbx1]

Was reading Glen Fryxell's great, free, downloadable pdf, book on lead bullets. In the section concerning casting fluxes, he discussed the advantages of saw dust as flux, explained the chemistry behind the recommendation, and said he liked walnut sawdust for a few reasons, including good smelling smoke.
I have been working on a bulk bag of walnut shell media forever, used with a tiny amount of oil to eliminate dust. Marvel Mystery seems to work well but I don't imagine that is critical.
Assuming I have adequate ventilation to deal with whatever might be in my various sources of alloys and scrap lead, would there be any reason not to recycle / dispose of the dirty media as a casting, or more probably, smelting flux?


Essay W

[mdi]

The one time I tried using crushed walnut shells (used) for a flux I got a large cloud of very acrid smoke that drove me out of my casting shed. Dunno if it was because it was used, (tumbled brass only, no additives), but I haven't tried is since. I use sawdust from my personal woodworking, prolly just cheap pine, without the same amount of smoke and it isn't really unpleasent...

[tomme boy]

Throw it away. Or use new media.

[wncchester]

You have it; try it.  Won't cost you a thing and then you'll know for sure.

[Reverend Recoil]

I tried it.  It fluxes well but stinks up my garage.  I prefer canning wax for lead fluxing.

[luckydawg13]

i use Jesus candle wax and sawdust

[tomme boy]

It is full of lead dust trapped in the media. DO not breath it.

[Land_Owner]

He's been polishing BRASS not lead.  Every flux is going to have lead fumes in it when burning and off gassing on top of the lead melt.  Good call on not breathing it though...