I've got some casting to do and with the cooler weather the PB looses it's stickiness. I was going to build a new heater with parts from the hardware store. Had to stop at Wallyworld first and spied a $20 electric skillet. Figured a little modification and it would work and be cheaper than piece built. Cut the sidewalls off so it's flat, cut off two of the handle mounts, used one of the leftover handle screws to pin the controller on, and stuffed wool into the cavity to keep sand out. I've got a spare handle now. This thing works so much better than my other one. It slices easily into the sand and there is a lot of surface area for faster heating. I set it on 300F, push it in for 30 seconds, pull it out and stab again. Took about 15 minutes to do the heap.
That's a good idea. I've been using an old stainless steel sink with a weed burner. I wanted to put the torch under the sink but it has a plastic sound deadener and stinks. I always have to heat mine because it's kind of dry. I'm afraid to add anything to it.
I would not be afraid to add to your sand. Not doing so more or less ensures decreased performance. I routinely add glycerin (glycerol) to mine to rejuvenate it as the alcohols in Petro do evaporate. Just pull out a couple cups of sand and try adding some glycerin 1 tsp at a time until it is nice and soft and packs well. Occasionally some oil may be needed as well since it gets burnt off a bit with each pour. Denis
I spritz denatured alcohol into my heap if it gets dry. I have the iron oxide and oil additives to make PB, but seldom add them. Before I built my muller I used a hand held kitchen mixer and the alcohol to condition my sand. I little goes a long way.
Gave the sand some lovin' today since it's sat for over a year. Bought a pint of Glycerin on Denis's advice and added about 2 ounce per mixer load and tumbled for 10 minutes. After I got it all back in the tub, took the heater to it. Found the best way to use it is to plunge it almost vertical, wait 15-20 seconds unit there's a wisp of smoke and pull back a little on extraction. That opens a gap and make the next plunge silky smooth. Just like hoeing the garden. Then I packed my 10 x 18 flask to pour a plaque. Boy, I'm rusty, failed to fill the corner across from the sprue. I think it was tilted too much and used a smaller than usual sprue. Nice shiny finish though, so temp was right. Try again tomorrow.
Being new to this I hadn't realized that my Petrobond won't work well if it's cold so thank you for that tip before I got started and ended up frustrated. Also, I love this method for dealing with the cold Petrobond. I'm going to have to swing by the local salvo shop and see if they have a cheap electric skillet to cut down!
Hi Riley, Glad you found this helpful. It's been so long since I've used new PB that I don't remember how it acts. Mine is black from casting a lot of large plaques which have a lot of surface area. I coat the mixer walls with oil and throw the burnt crust in first to try and replace the oil. I hope the glycerin helps too. I think you'll be hard pressed to find another skillet that cheap and also be that easily modified. But, good luck on your search.
