If you don't scrape the bottom with your stick, you won't get junk trapped in the alloy. The finings will make their way to the top eventually.
I can't wrap my mind around the concept. Scraping the bottom and charred wood will get trapped in the melt, only scrape the sides and it will make it's way to the surface. Eventually. Much of it will get to the surface but lead is easily dense enough to hold particles in suspension. How much of it is acceptable?
Some state that they won't flux with sawdust because it clogs the bottom pour spout. If it makes it's way to the surface how could it be clogging the spout much less not ending up in the bullets? The only possibility of burnt wood getting in the spout or the bullets is if you physically force it under the surface of the melt. By stirring with any sort of wood you are forcing it under the surface and some will be trapped there. It makes no difference if you scrape off pieces of wood from a stick by scraping the sides or the bottom of the pot, it is under the surface.
I'm not trying to say anyone has to do it my way, that's not my intention. There is however another way to look at this and no doubt some reading this thread will be interested. For me I am 100% sure that no charred wood is trapped under the melt to end up in my bullets because I do nothing to get it under the surface in the first place including (especially) stirring with wood, stainless only for me. I do like the hack saw blade idea though, will be trying that. Should be easy to form to the bottom curve of the pot.
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