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wlc
04-13-2012, 01:25 AM
This isn't a boolit casting question although it is a lead casting question. How much tin (% wise) should I add to get a mold to fill out properly when using straight stick-on WW? Thanks for any help.

Larry Gibson
04-13-2012, 03:13 AM
1 % will generally give good fill out. However, bringing the level of tin up close to that of the antimony (3-4%) will also strengthen the alloy and make the lead, tin and antimony blend better together. I've found that adding 2% tin to WWs give a better balance of 2.5+% tin to the 3-4 % antimony and most often brings the BHN for aged (10+ days) bullets up to 14 - 17 BHN with 16 - 17 BHN being the most common. The technical explanation is in Lyman's CBHs 3rd and 4th Editions.

Larry Gibson

Oops, just saw the "stick on". The above is for clip on WWs. With stick on which are pretty close to pure lead a 40-1 or 30-1 lead tin mix generally gives good fillout.

runfiverun
04-13-2012, 01:11 PM
it depends on how much detail you are trying to get too.
and the temp of the mold will really help fill out.
if you are making something with square edges then 2% is fine.
if you are trying to fill in a soldiers face and get his eyebrow hair to show then 3-4%.

Defcon-One
04-13-2012, 02:54 PM
runfiverun has got it 100% right!

There is a reason why Linotype, used to fill in small intricate letter molds, has 4% Tin. If you need fine detail use 4% Tin in your mix. For general fill out, 2% tin is fine and that's what I use for casting bullets (All but rifle!).

Whether starting with Stick-on WW or Clip-on WW a 2% Tin Alloy is still 2% Tin. The real difference is the Antimony, an alloy hardener, found at around 3% in COWW and not at all in SOWW.

If you don't mind me asking, What are you casting?

wlc
04-13-2012, 03:54 PM
runfiverun has got it 100% right!

There is a reason why Linotype, used to fill in small intricate letter molds, has 4% Tin. If you need fine detail use 4% Tin in your mix. For general fill out, 2% tin is fine and that's what I use for casting bullets (All but rifle!).

Whether starting with Stick-on WW or Clip-on WW a 2% Tin Alloy is still 2% Tin. The real difference is the Antimony, an alloy hardener, found at around 3% in COWW and not at all in SOWW.

If you don't mind me asking, What are you casting?

Split shot sinkers. Started off with just using the stick ons and they weren't coming out "full". I assumed my melt or mold was too cool, so upped the heat a bit. They did start coming out better, but still not completely filled out. Thats why the question. I'm just learning about casting in general and knew this was the best place to ask my question. This forum is a virtual treasure trove of information and I am so thankful to have stumbled onto it.

montana_charlie
04-13-2012, 05:07 PM
If you don't mind me asking, What are you casting?
Split shot sinkers. Started off with just using the stick ons and they weren't coming out "full". I assumed my melt or mold was too cool, so upped the heat a bit. They did start coming out better, but still not completely filled out.
Sounds like your mould is too cool. You should be able to get decent split-shot with pure lead.
Preheat the mould or cast faster ...

CM

geargnasher
04-13-2012, 05:54 PM
+1 CM.

Gear

wlc
04-13-2012, 06:32 PM
Thanks Guys!! I'll try running it hotter and see what happens before I add any of the solder I've run across. I'll save it for boolits if and when I need it.

runfiverun
04-14-2012, 02:36 AM
you want the softest lead you can get for split shot sinkers.
i tried making some from ww's and they were single use only.
they would break if you tried to open them and sometimes when you tried to pinch them on.
alloy temp of 750-775 and a mold temp over 350f will make good whatevers with soft lead.
as long as it's round or not too detailed.

fredj338
04-17-2012, 12:54 AM
Straight stick-on ww are almost pure lead, so 30-1 mix gives a more useful bullet IMO than just adding 1%. It cost more, but gives you a bullet that runs well over a wider range IMO.