I can pick up bags of either one at the local (really local, so good) home improvement/hardware store. Is one better for use as a insulating material for slow cooling blades for annealing? I'm just getting started in this stuff.

Thanks,
Barnaby

Barnaby. I use wood ashes from my fireplace. I keep them in a metal trough(bucket, tub, anything metal will do). When I anneal the steel I just pre-heat the ashes with a red-hot chunk of scrap and then put the steel in the ashes, leave until cool to the touch(I go 24 hours) and your blade should be soft enough to work. A disclaimer: I use old files and 5160 for my knives so my annealing process may be primitive. Other, more learned makers here should be able to fill you in on their process with materials more sophisticated than mine. Good Luck!

wood ash works fine for 5160. it works for me too. although i have heard both work equally well. good luck with getting the right stuff

I've use vermiculite with great sucess. Wood ash is ok but not suitable for larger pieces of steel in my opinion. Its insulating properties break down as time passes. Vermiculite is stable, and chemically neutral which can not be said for wood ash. You might get a better price on vermucilite from a builder supply. Vermiculite is often used as insulation in cement block installations.

At one time I had some truck springs from gravel trucks. They are on the order of 3/4 inch thick by 2 1/4 long.

I found that I had to bury material in vermiculite to get it soft enough for my saw to cut easily. It also took a good 15 min soak at temp to get the steel heated through also.

Advice given is good and leads you ahead. But why not get a bag of each, and a bucket of wood ash and do a test to see wot you like?

I agree that vermiculite would be a very stable medium for annealing. I just use wood ashes because I'm cheap.:)

well.... i got perlite, and nobody said anything about it being used.  I thought perlite was what I wanted and then realized it was actually vermiculite that I was wanting.  So I guess I will go with the advice above and just get a bucket of it set up and see how it works.  Hopfully I can report back in a few days and add my experience for future people to see.

I use vermiculite...works fine for me.

Good Morning,

Try garden Lime from the Hardware store or Garden center. It works well as Flux as well.

Neil

This is one way to resurrect a dead thread. 2009 to 2022.

Doesn't hurt too much...and as many folks have problems doing simple web searches; having it up at the top may help some of them.

I kinda like it when someone resurrects an old thread that I haven't seen or remembered.