Rangefinder
New member
I know I saw a question posted not long ago about zinc wheel weights in the smelting mix, but be darned if I can spot which thread it was in at a glance. SO, since I just put new tires on my truck today, thus picked up a nice load of wheel weights, THUS was "obligated" to do a little ingot smelting tonight, I thought I'd touch on the matter.
*****
First off, the junk weights that you don't want going into the mix are not difficult to spot with an initial culling of the "herd". The zinc weights that stand out first are the ones that are rivited to the crimp. Lead weights are poured to the crimp because lead is too soft otherwise. So, with a quick sort, pull off the ones with a crimp that is pressed or rivited to the weight. Not always the case, I've found plenty of zink alloy weights that were poured on, but the rivited ones are a sure cull.
Next, look at color and oxidization. I end up with gobs of wheel weights. They're always the ratty, nasty ones that really can't be reused. After a few road-miles and exposure, the lead ones are always a dark, dirty, chewed-up dull gray. The zinc ones still look pretty good. Set those aside.
If there is a question, give it a drop test. Drop it on end onto concrete. Lead is always a dull, dead "thunk". Zinc or zink alloy will have a tiny bit of ring to it.
Another indicator is that lead weights are always measured in ounces, and now sometimes in both ounces and grams. The zinc ones seem to be in grams only. I could be wrong, but I was paying attention tonight just for posting purposed and the zinc weights that stood out were in grams only.
Last but not least, pay attention to your initial melt-down. I do mine in a large cast iron pot over a medium propain heater, but try to melt slow while giving a stir every few minuts once the lead starts pooling. Watch the melt. If a weight seems to be lingering, yank it out. Lead weights surrounded by a pool of molten lead will puddle out pretty quick. Zink weights will tend to be a little stubborn. They'll float higher and don't puddle as quickly. So if you miss them in all the pre-melt culling, that is a last good chance to spot 'em and yank 'em out.
Hope that helps. Happy casting!
*****
First off, the junk weights that you don't want going into the mix are not difficult to spot with an initial culling of the "herd". The zinc weights that stand out first are the ones that are rivited to the crimp. Lead weights are poured to the crimp because lead is too soft otherwise. So, with a quick sort, pull off the ones with a crimp that is pressed or rivited to the weight. Not always the case, I've found plenty of zink alloy weights that were poured on, but the rivited ones are a sure cull.
Next, look at color and oxidization. I end up with gobs of wheel weights. They're always the ratty, nasty ones that really can't be reused. After a few road-miles and exposure, the lead ones are always a dark, dirty, chewed-up dull gray. The zinc ones still look pretty good. Set those aside.
If there is a question, give it a drop test. Drop it on end onto concrete. Lead is always a dull, dead "thunk". Zinc or zink alloy will have a tiny bit of ring to it.
Another indicator is that lead weights are always measured in ounces, and now sometimes in both ounces and grams. The zinc ones seem to be in grams only. I could be wrong, but I was paying attention tonight just for posting purposed and the zinc weights that stood out were in grams only.
Last but not least, pay attention to your initial melt-down. I do mine in a large cast iron pot over a medium propain heater, but try to melt slow while giving a stir every few minuts once the lead starts pooling. Watch the melt. If a weight seems to be lingering, yank it out. Lead weights surrounded by a pool of molten lead will puddle out pretty quick. Zink weights will tend to be a little stubborn. They'll float higher and don't puddle as quickly. So if you miss them in all the pre-melt culling, that is a last good chance to spot 'em and yank 'em out.
Hope that helps. Happy casting!