Kutter,
I've never had flash corrosion from heating too fast. But it is usually convenient to plug in the hot pot you will be heating your PNO3 or your lead pot and, at the same time, plug in your hotplate with the parts on it to be warmed. This is standard bullet casting procedure. The plate heats up gradually and brings the parts up to temperature with it. I do not know how hot my plate is, though I could measure it, if anyone cares to know. I just have it cranked over to 3/4 of max. I also throw a double or triple layer of heavy duty aluminum foil over the mould, part, or tool to be heated. This helps the piece warm evenly.

Doing this with the casting ladle is especially helpful since the grunge on any ladle seems to attract moisture from the air. Heating it minimized the vibration and "boiling" that comes from immersing it deep into the pot for that first helping.

If you have not worked with high temp liquids like this, you just need to be careful and wear only cotton, leather, or maybe wool clothing. NO NYLON BOOTS OR SHOES OR ANY SYNTHETIC CLOTHING! Lead goes through synthetics much faster than a hot knife through butter. A shooting friend dropped a pot of lead on nylon hiking boots with disastrous results.

I have once time poured hot lead into a cold, dusty/dirty Bar ingot mould. The dust and dirt had accumulated some moisture and the mould emptied before it was even close to full. Some lead got thrown around the garage and the lesson was learned. Clean, dry, warm is safe. Everything else is not.

_________
BrentD, (Professor - just for Stan)

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