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Danner
05-03-2009, 12:12 AM
I've read alot of threads here this evening on zinc and have some questions I melted down about 50lbs WW this afternoon and about the same of linotype The linotype ingots are kinda shiny and the WW are dull and almost look galvanized should they look the same or do I have zinc in the WW

Down South
05-03-2009, 09:29 AM
The dull gray galvanized color is what my ingots look like and is not an indication of zinc. Ingots can look shiny sometimes if poured at cooler temps. I am not saying that you DON’T have zinc in your ingots but the color and description you described is normal.
I’ve only had one pot of WW that was contaminated with zinc and I knew it while it was still in the smelting pot. I kept getting an oatmeal type slush on top of the melt. I finally gave up on trying cleaning it and reserved that batch for the 1 lb sinkers that I make.

Down South
05-03-2009, 09:36 AM
Sorry, Double post. Weather is getting bad here. The same system that collapsed the Cowboys practice dome is just getting here and I'm on Hughes. Te storm system is causing connection problems.

Danner
05-03-2009, 10:16 AM
Thanks, I'm going to try and cast some boolits this morning and see how they turn out. I guess I haven't seen the oatmeal look so maybe I'm ok. I do recall some of the WW being painted gray and shaped alittle different. I don't have a thermometer but I do have a heat gun.Anybody had any success using a heat gun for checking temp?

SciFiJim
05-03-2009, 10:32 AM
How would you use a heat gun for checking temp?

Danner
05-03-2009, 10:37 AM
How would you use a heat gun for checking temp?

I could point it at the mix as I stir?? or at the outside of the pot.

SciFiJim
05-03-2009, 10:52 AM
Are you talking about a digital thermometer or a hair dyer looking thing that generates heat? The digital thermometer might work if the upper range is high enough. Mine only goes up to about 500*, so not hot enough to measure melting lead.

mooman76
05-03-2009, 11:00 AM
I have heard that because lead is shiny when melted you have to float a piece of steel in the lead to get a good temp.

SciFiJim
05-03-2009, 12:20 PM
I get a good temp in a three quart sauce pan on the side burner on my gas BBQ. I wrap foil around the base to act as a wind barrier and put foil over the top of the pan to hold in heat while melting. I can get 12 lbs of cold ingots melted and up to casting temp in about 15 minutes.
I bent a small v shape onto the lip of an old soup ladle to pour with. The only steel I have had in my lead was the clips when I melted down the WWs.

When melting down WWs the clip ons melt before the stick ons. As soon as the stick ons are melted I start skimming. The zinc and steel weights are still hard and are easily skimmed off with the clips.

To reassure yourself that the zinc weights melt at a higher temp than the stick on weights, first find a stick on that you know to be lead by testing for softness, then clamp the stick on weight together with a zinc weight in a pair of vice grips. Take a propane torch to them and the stick on weight will melt first. Keep heating the zinc weight and see how much more heat has to be added before it will melt. If you don't want to melt all of your stick on weights together with your clip ons then just put one small stick on in with your clip ons and use that as your temperature guide. When it melts start skimming.

As long as you pay attention when melting down weights and skim just after the stick on weights melt, you will not have a problem with zinc melting into your alloy.

Danner
05-03-2009, 12:21 PM
I just came in From casting about a 100 boolits or so. they seem to look ok and weights are .5 grain of each other. Next time I do WW I will try to look them over alittle closer I didn't get to try my temp gun the batteries are dead