Issues with Casting Lead Roundball

Weapontech

Weapontech

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Casting black-powder roundball and Mini-ball has been something I've done, off and on, for several years. It's always been a great way to spend quiet time after a crazy week, just relaxing and casting bullets.
My .490's and .600's have always come-out looking perfect.

Lately, I've been having a problem with what I can only describe as folds (spiral lines) appearing near the sprue (in some cases everywhere) on many of the finished casts. (I use a ladle, not an auto-spout from the lead melter)
I've been trying to resolve it by messing with everything from flux, to adjusting the heat of the lead, hotter mould blocks, etc, etc.

Anyone have a definitive answer to help me resolve this problem?
Many thanks in advance for any help!
 
Either the mould is cold or the lead is.... try warming your mould on the top of your pot....
At least that works for me....
Did you put some preservative material on your blocks before putting them away, some material can be very hard to get rid of....
John
 
Sounds like it might be a combination of too slow a pour speed (lead is spiralling in and setting before it's topped upand possibly lack of venting. You might have to increase the hole size in the sprue plate one drill diameter larger or provide venting by lightly chamfering the edges of the mould along the top parting line and or loosening the sprue plate a smidge.

Use a hard Arkansas stone to just barely chamfer the top edges. If you enlarge the sprue plate hole re-taper it from the top. After this get a piece of plate glass, a sheet of 600 grit sand paper and carefully lap any burr from the bottom of the plate that may have been raised by drilling.

Also check your ladle and make sure the pour hole is not being restricted by slag etc.
 
I would vote for a cold mold or cold lead either of which will cause wrinkles. Oil on the mold blocks will cause dimples and I find that I have to splash acetone onto the blocks to get rid of the oil. You could try sooting the inside of the mold using a coal oil lamp with no chimney.
If the lead is too hot, the balls will probably come out frosted. A final thought is to add some wheel weights to your mix, assuming you are casting pure lead. It assists in filling out the mold and it lowers the melting temperature as well.

cheers mooncoon
 
Are you using a new batch of lead??? Any possibility that you picked up some with a bit of zinc or other "non cooperative" metal mixed in? I melted down a bunch of wheel weights a while back in about 11 different melt batches. I had one batch that just would not cast smoothly no matter what I did with it. I dumped the pot, and started with a different batch, and my problems were solved instantly. I tossed that batch in the recycle bin at work. I just hope I don't have any other surprises down the road.
 
blacksmithden said:
Any possibility that you picked up some with a bit of zinc or other "non cooperative" metal mixed in?
Click to expand...
This last batch of lead that I used was recycled from mini's that I had made some time ago; they came out perfectly at that time. The other interesting issue is that every fourth or fifth casting in the batch I'm having problems with now, comes out perfectly. All the others have the problem I described earlier.
 
well since were on the topic of casting..hope you dont mind if i hijack the thread for a minute.in fact it might help out with your problem also..
anyways..in melting the lead you have to reach about 900 degree,s to pour lead..
how do you,s hold this temp.?i seen in some readings ive done ,a thermometer being used.
but were would you get one in the 900 degree range?
thanks and hijack over:pirate:
 
fogducker said:
......in melting the lead you have to reach about 900 degree,s to pour lead..how do you,s hold this temp.?i seen in some readings ive done ,a thermometer being used.
but were would you get one in the 900 degree range?
thanks and hijack over:pirate:
Click to expand...

Hijack away, the more info discussed....the more questions get answered.:rolleyes: ......or maybe, just more questions.....
I use a combination of electronic controlled lead furnace, and digital thermometer with a 1200 degree limit. Typically, 850 degrees for soft lead and 750 degrees for alloys with tin are the temps that I have used most successfully. The furnace is pretty good at keeping the temperature consistant.
 
fogducker said:
ok maybe one more hijack:redface:
if you dont mind,were did you get the thermometer with the 1200 degee limit?
Click to expand...
It's an IR thermometer. They work really well, and are very accurate.
You simpy point it at the surface, and press the button.
Price was about $200 a year or so ago.

Made by Extech Instruments, Model 42540. Here's the specs on it;
- Temperature range from -58 to 1400°F (-50 to 760°C)
- Handheld design, with trigger activation & hold.
- Digital display, multi-level readout
 
Weapontech said:
This last batch of lead that I used was recycled from mini's that I had made some time ago; they came out perfectly at that time. The other interesting issue is that every fourth or fifth casting in the batch I'm having problems with now, comes out perfectly. All the others have the problem I described earlier.
Click to expand...

Ok. I'm going to guess that you've already tried messing with the temp and with getting the mould a bit to hot and too cold, and you're still having this problem. Usually, going too hot will get rid of any wrinkling problems and just make things frosty. You're using lead that you know has worked in the past. Here's a long shot, but, has it been a long time since you last made a batch?? Casting to some is one of the "black arts" for lack of a better term. Is there something that you're doing (or not doing now) that you were doing then??? I don't know what you've got for a setup, so I don't know what variables there are. If you've got a bottom pour pot, you're using a mould that you've used with success before, then there really isn't much to vary.
If you're using a dipper, you could be pouring slower, you're pouring a little higher above the mould, you're tipping the mould a little more than before, did you just re-smoke the mould and it needs a bit of break in time to settle down, you're not hanging your tongue just right??? :D......just throwing out ideas here. If you cast regularly, and you're doing everything exactly the same as every other time, the only real variable is the lead, and I'm still leaning towards that. If you've tried everything else, get that batch out of the pot and try some other stuff. That's all I can really offer. Good luck.

BTW. I've never measured the temperature of my lead. I just keep going until it's hot enough that I'm not getting wrinkles anymore. If some are frosty, I don't really care, and I've never noticed a difference in the way the dull ones shoot compared to shinny ones.
 
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Most anyone dealing in moulds and casting equipment has thermometers, RCBS, Lyman, The Lead Man, .......check the catalogs. Without knowing the temp, how can you be consistant from batch to batch? Every mould or mix seems to have its favorite temperature. In this case, get your lead temp up and cast fast, your first four bullets are wasted getting the temp up for your fifth that's okay. Keep your speed up, don't dawdle and the 6th, 7th, 8th will be okay also.
~Arctic~
 
Again, it sounds like a temperature problem. Perhaps you are casting too slow. Like pour, let harden, set down mould, go give S a hug, drop the ball out and fill again thus giving the mould too much time to cool . I find that I get a rhythm going where it is one pour after another.
May also be contaminated mould. Is it rusted or oily? Give it a good cleaning and then soot it with a match or lighter. I use Rapine Mould Release (graphite particles suspended in alcohol which evaporates and leaves the graphite) and it works great.
 
theDuck said:
Perhaps you are casting too slow........
Click to expand...

Or, as it turns-out......pouring too slow may have been it!

I have managed to cast about 85 without a problem. Although I'm not exactly sure what may have resolved it!! :runaway: I cleaned the mould once more & re-blackened it using a lighter this time (used to use matches). Increased the heat by +10 degrees, and decided to pour a little differently. One, two or all of which seem to have resolved the issue for now. Thanks to everyone for their comments!!

Time to relax, and cast! :popCorn:
 
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