Can't get a nice casting.

[Jaak]

Here are the pictures of my problems. (http://imgur.com/a/oS0qp#0)

I am casting using straight COWW and having no promblems with the fill out along the driving bands (the picture looks like I do but that's a problem with the picture. The problems I am having are "folds" in the bullets and "milky stains" on the bullets. The bullet with the fold is the best of the batch, there rest are a lot worse and not one cast gave me nice bullet. The other two bullets have the "milky stains" but I can't seem to get a good picture of it.

I am using a PID and have adjusted the temp from 600-800 in increments of 50 degrees to no effect other than getting frosty bullets with folds. I have heated the mold by dipping to the point where the lead in the mold takes over a minute to cool and get good results but that seems overkill. I have degreased the mold using Dawn, pure alcohol and carburator cleaner, all with the same results. I even cast with out lubing the mold just to make sure there was no lube getting into the cavity.:veryconfu

What am I doing wrong?


P.S. The mold is a Lee 311-100-2R. (.32 cal)

[MtGun44]

Mold's too cold. Cast as fast as you can, fill, cut, dump, fill, cut, dump, do not stop
to inspect or admire your work. Max possible speed to put heat into the mold.
It may take 25 casts or more to get up to temp, and if you slow down it will
take more.

Then slow down as the mold comes up to temp, like when you said it was taking
a minute (sounds like an exaggeration to me) to solidify. Then cast more slowly
or even cool down the metal if you are staying too hot. Imagine that each time
you cast you are added a "packet" of heat to the mold. How quickly or slowly you
add packets (packets per minute) will control the mold temp.

The std answer #1: for all new casters is "Because your mold is dirty and not hot enough"

You might be clean, but the brake cleaners can leave crud in some cases. You are
almost certainly casting too slow, admiring your work, sorting the sprues from boolits,
fiddling and adjusting, etc. Too few 'packets per minute'.

Bill

[JIMinPHX]

Did you flux the lead real well?

[runfiverun]

I dunno bill.
the rest of the boolit looks real good, nice fill out and everything.
this looks different.
like maybe a drip of cold lead is going in the mold and then it's being poured around.
or the boolit is shrinking in or collapsing right there.

[David2011]

Hi Jaak,

Welcome to Cast Boolits. I think Fiverunfive is on the right track. Your metal may be cooling a little in the spout and freezing when it hits the mold. The mold may be cooler than optimum as well. I've had the same thing happen a few times, mostly when I pause to do something that breaks the rhythm of casting.

Remember two things when you're casting. The first is that you have to run a steady pace. The second is that the pace at which you cast has a bigger influence on mold temperature than the temp of the melt.

A PID is a nice enhancement but lots of boolits have been cast over campfires. A PID is kind of like a top end DeVilbiss paint gun to me. It would be a waste of resources in the hands of one of the decorating experts on DIY who never releases the button on the top of a rattle can.

Set the PID at -pick a number between 700 and 750- and leave it there. Cast a bunch of boolits fast, with the expectation that they won't be good, until they start coming out good. Shove them aside and start making keepers. Keep a steady, fairly quick pace. If you go to slowly the melt near the spout on your pot may cool. If you start getting heavy frost on your boolits, the mold is at the upper end of the useful temperature range. Shiny to lightly frosted indicates a good temperature. If you can't cast fast enough to end up with frosted boolits when you go as fast as you can then the melt may be a little cool. If you can't cast slowly enough to get shiny boolits then the melt may be too hot. Melt temperature is just one factor in casting good boolits. Use it as a fine tuning element and keep trying. Your picture looks like you are very close to excellent boolits.

David

[Jaak]

Then slow down as the mold comes up to temp, like when you said it was taking
a minute (sounds like an exaggeration to me) to solidify.

It sure felt like a minute, I held the mold to the lead for a slow count of 30 because I getting frustrated at this point, filled the mold and stopped counting at 30 seconds as the lead was still not frosting over. But when it finally did I understood why it's called "frosting over".

[Jaak]

Set the PID at -pick a number between 700 and 750- and leave it there. Cast a bunch of boolits fast, with the expectation that they won't be good, until they start coming out good. Shove them aside and start making keepers. Keep a steady, fairly quick pace. If you go to slowly the melt near the spout on your pot may cool. If you start getting heavy frost on your boolits, the mold is at the upper end of the useful temperature range. Shiny to lightly frosted indicates a good temperature. If you can't cast fast enough to end up with frosted boolits when you go as fast as you can then the melt may be a little cool. If you can't cast slowly enough to get shiny boolits then the melt may be too hot. Melt temperature is just one factor in casting good boolits. Use it as a fine tuning element and keep trying. Your picture looks like you are very close to excellent boolits.

This post just blew my mind. Melt temperature being dependent on casting speed of the user. I must have read other posts explaining this exact idea and it just never "clicked". Time for some late night casting.

[runfiverun]

it's a compromise of sorts.
you have to have the alloy melted and in a liquid state.
you have an optimum temperature to cast at, this is 75-100f over the melt temperature of the alloy.
you regulate your fill speed.
how you fill the mold.
how fast/soon you cut the sprue.
how quickly you can get the boolits out of the mold, close it, and get it back to being filled.
all of this influences your casting rate and consequently the mold temp.
if you do the empty,close,and fill quickly, you will add a little time to your count for the sprue cut or lower your alloy temp the the 75-f over liquid area.

[somedude101]

Does anyone think it could be a venting problem mabey he should look at the More " Lee - Lementing " sticky.

[44man]

It kind of looks like what we get when we pour a soft nose first. Looks like the first metal in the mold cooled before it filled the rest of the way.
I would look at the pour spout and adjustment of the flow.

[kweidner]

When I have experienced that is was a flow issue. Try pouring on the edge of sprue hole and let the lead swirl into cavity. Don't pour too slow it should take less than a second to fill a cavity. If it is filling too slow clean you spout on pot.

[Sasquatch-1]

Do you use a thermometer with your PID? I was just reading another thread where the guy had just finished installing a PID on his pot and found that the PID read out and the actual temp of the lead were about 300 degrees off. Also you never mentioned how many cavities your mold has and whether this is happening in all the cavities.

[detox]

When I have experienced that is was a flow issue. Try pouring on the edge of sprue hole and let the lead swirl into cavity. Don't pour too slow it should take less than a second to fill a cavity. If it is filling too slow clean you spout on pot.

You are using a bottom pour pot? Increase the flow like kweidner said. Or use a ladle.............

Double check casting temp using a standard casting thermometer.

[Wayne Smith]

I don't know about anyone else but I see no pictures?

[44man]

I don't know about anyone else but I see no pictures?
You have to click on the blue line.

[44MAG#1]

There always have to a simpleton in every bunch so here i go.
Can you shoot well enough to tell the difference between near perfect bullets and you normal looking castings?
Pick ten near perfect bullets and ten of your pitiful castings and load them with your favorite load and go to the range let someone else load the ammo in your gun not letting you know which is which and shoot both batches of bullets under careful controlled bench rest technique and see if you can. If you can't guess what, don't worry about it. Cast load and shoot. You can always pick out a few perfect ones to carry in your pocket to show your buddies or to photograph to impress.
Really I am not trying to be a smart alec just trying to give some advice that will useful until you get your casting technique improved.

[JIMinPHX]

Does anyone think it could be a venting problem mabey he should look at the More " Lee - Lementing " sticky.

That would have been one of my next questions, assuming that he said his lead had been cleaned real well. Since he said that he got to the point of frosty boolits, that means that the mold was at the high end of the acceptable temperature range, so that would rule out cold blocks being the problem. Adding 1-2% tin may also help. A 3" piece of 1/8" diameter 95/5 lead-free solder per pound of lead adds about 1%. A 6" piece of 50/50 does the same thing. If that didn't help things out, I'd go for the vents or a better cleaning or get a fresh batch of certified alloy from someplace trustworthy.

[MtGun44]

HMM. Either the pics were added later or I missed them.

Maybe a bit more tin, or a dirty spot on the mold? It still looks like
these have not gotten up to 'frosty' yet, and until they are there
I tend to think that hotter will be better. Most of my casting
problems have been 1) alloy low on tin 2) dirty mold 3) not
hot enough.

Nowdays if I think the mold is clean enough, I cast faster until
I get frosty and then back off. If still not filling out well
everwhere, I add some tin. Rarely have to fiddle beyone that,
but sometimes loosening the sprue and cleaning vent lines
is needed.

Scrub cavity with Comet and toothbrush. Cast fast until you
are certain that things are hot enough (may take more heat on
pot) and if still there, add some tin.

Bill

[popper]

Funny metal in the melt? Looks like a stress crack due to uneven cooling.