Today was learning curve day.
I fired up the lead melting pot to make some one inch round ball and slugs.
My slug mould has made a lot of slugs for my cannon, but the base plug stopped working a long time ago. To use it now I simply use a piece 2" x 4" with a hole drilled it and put the base plug in the mould up side down. I have to find a 1 1/2" piece of round Alumimum scrap and make a new plug.
The other mould I have is the inch round ball. I haven't used this mould much as I got it just before I went to SA. I have never got a good cast from it. The casting session last week seemed to indicated that the mould wasn't hot enough so I tried preheating the mould today. Still no full fill out. Looking at the mould, I notice it has a big side vent, but the wrinkles are in the areas where there is no venting wrinkles. I seem to remember have the same problem with the slug mould. I am going to have to scribe some vent lines in the mould face.
I also fired up my big burner and tried melting some zinc. This isn't the furnace I am going to build. It's just a gas burner with the crucible sat on top. The learning curve for casting zinc is steep. The key seems to be preheat the mould and keep molten metal trickling into the sprue. A different mould design is called for. But this is what I have and there is no budget for anything else. None the less I did get some round balls.
I definitely need the furnace for zinc. Open burner just wastes a lot of heat and is slow. I'll use the burner to preheat the moulds. The lifting and tipping hook set up for the crucible is good. The heaviest lifting is from the burner and back. The crucible is seldom more the a few inches off the ground. Carrying is easy. The pour takes some practice.
I'll use the open burner for mould preheat and the furnace for metal melting.
