BXA QCTP

[ETC57]

(03-09-2012, 08:38 AM)rleete Wrote:

(03-08-2012, 06:46 PM)DaveH Wrote: How will you heat it up and cool it slowly?

Use sand. Get an old sauce pan (do NOT use the wife's!), and some play sand. Sand you can get at any home store. Fill the pan deep enough to cover the holders plus another 2 inches or so. More sand is better than not enough.

Using some sort of burner - I use an electric one - heat the pan and sand. Just put it on high and leave it for a bit. Stirring might help, but I just leave it on high for half an hour or more. It might smoke a bit (impurities in the sand), so I do it outside.

Take a torch (propane will do) and heat the holders up. Get them as hot as you can. Plunge them into the sand, and leave for another half an hour. Keep the pan on the heat all this time. You want the holders burried in the sand, but not touching the bottom of the pan. Use a cover on the pan if you can.

After half an hour, turn off the heat. Leave the pan sitting there for a while. I usually try to do it in the morning, and not touch anything until the evening. I've used this successfully a couple of times. The key is to have the sand hot before you put the parts in, so it doesn't suck the heat out of the part and quench it.

rleete,

good idea. I like it! A kinda hot box setup, that one will defiantly go in my how to book. much easier to keep sand at a constant temp than air.