tin question from a noob

[johnh57]

I have a new Lyman .45cal 4 cavity mold - 200 gr swc, bb. I hadn't yet set up a hot plate to pre-heat the mold. Yesterday I wanted to test a new sizer die I made so I dropped a few boolits. I cast about a dozen drops into all 4 cavities and returned them to the pot just to warm up the mold. After a dozen or so casts I was still having troubles getting sharp corner definition. I cast probably 10-12 more drops that I kept to mess with the sizer. The melt is 100% WW. It seems to do fine on a 2 cavity 358156 mold. Using a Lee 10 lb bottom pour - set on about 9. I do have a lead thermometer - just didn't think to use it.

I'm wondering if I need to add a bit of tin for flow?

Dropped in the hardware store yesterday figuring to pick up 3-4 lbs of 50/50. Its been a while since I bought solder but I was sticker shocked to say the least (ACE wanted $22/lb for 50/50). I see Rotometals has pure tin for around $16 - $18/ lb. By the lb this is 1/2 of what it would cost to by hardware store solder for the tin content.

I've made Lyman #2 in the past which IIRC is about 5% tin.

I did the smelting of the WW a couple years ago and knew about watching for zinc - I don't think I have any zinc in the melt. I tried to keep the temps down and pull the floaters out of the melt.

Is tin the right direction? Any problems melting pure tin directly into a melt (I'd do that in a separate smelting pot)? Or should WW fill out a larger cavity mold ok?

[captaint]

john - To me, it sounds like your mold is not quite hot enough. The reason the 358156 worked well is, it's a 2 cav - and they heat up much faster. Try to keep pouring with the 4 cav. It might take 10 minutes of constant casting to get it up to temp. Just pour as quickly as you can and when the boolits start to get a little frosty, they should start to fill out well. OR you could try adding a little tin. I use Pewter for mine. I buy used "junk" pewter from the 2nd hand stores. Fairly cheap, and the pewter is about 90% tin. BUT - do make sure it is real pewter. If the item is thick or doesn't bend easily, it aint tin. If it looks like aluminum, it probably is. You must look for the stamp on the bottom. After a short time, you'll see what I mean. If it's not stamped, don't buy it. Good luck. Mike

[Cmemiss]

Another thing, and I'm sure someone with more experence will chime in, is that it takes two or three casting sessions for my molds to start to produce really good boolets. First session I have maybe a 40% rejection rate, next time it's maybe 20%, then things settle down and very few rejects go back into the pot. A little tin wouldn't hurt. You might want to look around for some pewter at a junk shop or yard sale, that's sometimes a good source for tin cheap, especally if you can find some of those commerative beer mugs that were popular years ago.

[johnh57]

Thanks! I'll try again. I picked up a hot plate and dug out a lead thermometer and a probe thermometer good for 500 deg.

I don't have handles yet for the mold - so i jury rigged a couple pieces of 1/4 plate and mounted them to a wooden clamp. Might be too much heat loss from the kludge handles. Should get some lee handles Tuesday to adapt, and I'm waiting for RRR to get me a price on his delivered.

John

[joesig]

Thanks! I'll try again. I picked up a hot plate and dug out a lead thermometer and a probe thermometer good for 500 deg.

I don't have handles yet for the mold - so i jury rigged a couple pieces of 1/4 plate and mounted them to a wooden clamp. Might be too much heat loss from the kludge handles. Should get some lee handles Tuesday to adapt, and I'm waiting for RRR to get me a price on his delivered.

John

I made Lee handles work, once. I would suggest Lyman or RCBS if they fit.

Hot molds will certainly help fill out. I rest mine on the edge of the pot while melting the alloy. You will know if/when the molds are too hot by the frosty boolits.

You won't need to add much tin, if you are inclined. Check for 95/5 solder (Tin/Antimony) aka lead free. At 1% that spool will treat about 100 lbs of WW. not too bad when you divide it out per boolit.

[Larry Gibson]

Add 2% tin to your COWWs. They are very low in tin to begin with and depending on the batch/mix you have they may have close to no tin. The tin mixes with the antimony (up to a certain % of each) and makes it go into solution in the lead. This makes for a much better alloy to begin with. The addtional benifit of that is much better mould fill out.

Larry Gibson

[BadDaditood]

Handles?!?!? Reminds me of the funniest post i've seen in my life... Must reading

http://castboolits.gunloads.com/show...-top-this-NOPE

[johnh57]

LOL! that's good.

Real men don't need no stinkin' handles!

Mold did much better with a hot plate pre-heat and minding the melt temps.


right up until I tried a touch, just a touch, of 2 cycle motor oil to lube the sprue plate.

sigh

[Springfield]

Tin is over rated, I get fine fill-out with 50/50 WW and pure lead. Just get the mould hot and keep up a good cadence.

[fred2892]

I find it depends on what you are casting. I don't add tin to my alloy for any standard 38/44/45 boolits, but find it essential to add tin for small cavities (.22, .25), any hollowbase/hollowpoint and large (.50 +) moulds.

[shadowcaster]

Definitely get your mold up to temperature and keep enough of a cadence to keep the mold at the right temp. I have to agree with Springfield on how tin is over rated. More often than not I don't add any tin. Sometimes tin is necessary for good mold fill out, but I feel that more than 1% tin is a waste at today's prices.

Shad

[BadDaditood]

Today i cast a few with a new batch of 50/50= SOWW and dental x-ray which is 98% Pb, 2% Sb/Sn. These are the purtiest boolits i've cast in decades.

[i have a bunch of tin rich alloy i made before the turn of the century, back in the Dark Ages (pre-CastBoolits). I would get wrinkled fillout, add solder, wrinkles, add solder until mold got hot enuff to fill out. Now i have a whole bunch of pricey *pot-sweeteners*]