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Mad Mucus
11-18-2019, 05:44 AM
I'm interested in casting 1" cannon balls from zinc.

Anyone with experience have melt tips including recommended zinc alloy mixes and ratios for consistent pour and smooth finish, shrinkage % etc.

klenke.ryan
11-18-2019, 07:27 AM
Following. I save all my zinc WW for making ingots. Curious is the melting process is similar to lead. Not going to make bullets with it though.

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jdfoxinc
11-18-2019, 11:39 AM
Zinc melts at 850 deg F. A friend of mine casts 3lb ball for his Verbrugen cannon out of pure zinc.

Valornor
11-19-2019, 10:39 PM
I’m kind of curious on this too. Would love to see how people do this and control the slag.


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Rcmaveric
11-20-2019, 01:29 AM
Melt your zinc wheel weights and add 1% aluminum and 1% tin. Just take some coke (or beer cans, pick your poison) cut them up and toss them in the molten zinc. They will dissolve in. Tin will lower the melt temp and help the allow flow. Aluminum also lower the melt temp and lowers the surface tension.

Look up Zamak (I think that's the name) that's your best basic zinc casting alloy.

For tools, use iron and cast iron. DO NOT use anything made of steel or aluminium. Zinc is a highly reactive metal and will dissolve steel and aluminum like sugar and water.

For fluxing, borax works as well as our normal fluxes. This isnt rocket science. I think I heard someone mention aspirin once because it was a type of acid. Don't quote me, I just used my normal saw dust and pine stick. No problems.

That's the most of my knowledge and experience with zinc. So far I only have made ingots with it. I don't have a cast iron molds so I can't cast anything with it.

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bikerbeans
11-20-2019, 06:38 AM
There is a thread in the shotgun subforum about using Zamac to cast 12ga fullbore slugs. My search skills don't allow me to post a link.

BB

country gent
11-22-2019, 11:29 AM
Several things about zinc is It runs hotter than lead much closer to 1000*. low isn't the same as lead and may be grainy just pouring. Zinc and alloys of are normally ran in a die cast set up where a closed mould is filled under pressure with a shot tube, this pressure alleviates the graininess and gumminess of the castings. Flux is a borax based material, in the plant we had what looked like hot melt glue balls that were used to flux the pots. ( our pots were 2 40,000 lb and one 50,000 lb) Metal came in molten on a hot truck.

JonB_in_Glencoe
11-22-2019, 02:23 PM
typically Zinc wheel weights (in USA) are cast from Zamak 3
https://www.dynacast.com/zamak-3
Melt temp is 384ºC ±50 (723ºF)
Since there already is 3 to 4 percent aluminum in there,
I'd just add 1 or 2 percent Tin for better fill-out...I'm not sure it will lower melt temp? but I think it will.

Bookworm
11-22-2019, 07:53 PM
I rendered all my Zn weights, and cast them into ingots. I didn't take any special steps, treated it just like Pb weights, but higher temp. I used the same sawdust to flux, but didn't bother with wax fluxing, as all I was doing was clearing out a bucket.

When pouring the ingots the melt seemed somewhat thinner than Pb, easier to pour.

The only use I have for the Zn, at least so far, is to use it to grease the skids when obtaining wheelweights.
When I was at my regular place, one of the employees complained that if I got the weights he wouldn't have anything to use for fishing. I went home and fetched some Zn ingots and gave them to him.
That freed up the bucket of lead weights for me.....