Okay... need help with frosting and fillout

[Bazoo]

Im having some problems, that i've previously not had much, and I need some advice. Ive cast 38s and 44 and 45s and 30 caliber projectiles previously with no problems with the same moulds, pot, and ladle.

But now, im having this problem. I get incomplete fill out on the driving bands with varying degrees of frosting from none to complete. I've tried a couple different heat settings, and consequently several different mould temperature ranges. I am running a lee 430-310-rf, that previously run okay when just below frosting temperature. So I switched to a lee 30 caliber mould that I know runs good.. and I have some better success, but not as good as the mould normally does.

I am using straight wheel weights. But I aint using ingots, im melting them right into my pot and fluxing with sawdust and beeswax. I know it aint right but its been working for me a while.

Fluxing with beeswax as needed between pot fill ups.
I've cleaned my moulds with brake cleaner or lighter fluid.
I ran them dry a short period for a base, and then lubed with the tiniest amount of synthetic 2 cycle oil to make sure that I wasnt getting contamination.

I dont have a thermometer. Im using a lee pot and lyman dipper.

I think, my problem is the melt is not hot enough. Edit, I also think that It could be I got a small batch of bad lead that either aint got enough tin in it or something else with it aint right.

I had a few months not casting, and I left my pot outside on the covered porch, and it rusted. I wire brushed it and went to work, but Im thinking that the heating element might have rusted inside and is affecting the amount of heating vs the numbers that i've previously used. I had the melt hot enough that I was getting purple on the top if I left it for a long break, then I cut it back some.

So... Do i need to add tin? Is my melt not hot enough? Im I just stupid? What Am I missing this go round?

Thanks for the help.

~Bazoo

[Joe K]

I have experienced this also. When heat adjustment didn't help, I would add tin and have good fill out. Now I mostly use half coww, half range scap and an ounce or so of pewter tin for most of my casting. I am sure the more experienced folks will be along soon. Hope this helps.

[Bird]

If you can get frosty bullets, then everything is hot enough. I have never added tin, but you may need to.

[David2011]

Frosting is not a problem in itself. As the mold gets hot the alloy cools more slowly. Slow cooling allows antimony crystals to form which manifest as frosting. I suppose it is possible to get the mold too hot with an under temp alloy bit not sure how. You would be casting really fast to do it, I think.

When you pour, do you pile a big puddle over each cavity? You should do that and you should see the center of it "suck in" as the boolit cools and shrinks. That is essential to get good fillout.

Can't really help diagnose the amount of heat you're getting but if you get it working again keep the pot our of the weather!

You might open the pot up (unplugged, of course) and inspect the heating element. Make sure the connections aren't corroded or rusted. If it's an old pot it may have asbestos in it so wear a good respirator. Is it the 4 pound pot? Does it have a thermostat? (I have an old one that doesn't.) I've never measured the temp of my 4 pound pot but it gets really hot by seat of the pants judgement, hotter than necessary for the alloys I use. I just use it to melt sprue to dump back into the big pot.

Clean the pot so you know it's not contaminated.
Melt and clean your ingots elsewhere; not in your casting pot. WW are filthy and you're probably contaminating the pot.
Flux with sawdust every time you flux. Don't worry about beeswax.
Clean the mold again. Add Soft Scrub or Dawn with a soft toothbrush as a final cleaner after the solvent cleaning.
Lube it when hot with boolits in the cavities being very careful to keep lube out of the boolit cavities. Only lube to bottom of the sprue plate, the top of the mold but avoid the cavity edges and the sprue plate pivot. The correct amount of 2 cycle lube is: shake the bottle, take the lid off. Touch a Q-Tip to the inside of the lid. It should wet about half of the Q-Tip cotton. That's plenty for a 2 or 4 cavity mold. You want the thinnest possible film of 2 stroke oil and no more.

Tin wouldn't hurt but as you've read, 2% is plenty. More is wasted money.

The best measure of your mold temperature is the time it takes for the sprue to freeze. It should go from molten and shiny to dull gray in 3 to 6 seconds. If it takes longer the mold it too hot. Shorter, the mold is too cool but it would probably be wrinkling the boolits. Sorry if I'm repeating things you know. Mold temp is controlled by the casting rate more than the temp of the melt. The faster you cast the hotter the mold. I have only cast a few boolits with a ladle so don't know how hard it is to get a small mold (as opposed to great big rifle boolits) hot with a ladle.

Can you get your hands on a pound or two of pure lead/stick on WW? Straight lead melts at 621 degrees. If it sits in the pot for a while and turns blue and gold on the surface it's getting hotter than the melting point. Lots of people have cast lots of boolits without a thermometer but they come in real handy when you suspect a problem with the pot.

Well, I've been thinking and typing for an hour and that's all I can think of right now.

Good luck!
David

[lwknight]

The first thing you really need more than anything else is a thermometer. Frosting means that the mold is a little too hot.
It does that because the bullet is cooling slowly. The lack of fill out is more likely from too low casting temperature.
Yes you can get the mold too hot with too cool alloy.
P.S. Get a thermometer!

[Grmps]

+1 on adding 2% tin modern wheel weight don't have the same alloys that they used to have

[Bird]

Top off your lead pot, and, or increase the flow from the spout.

[hermans]

The first thing you really need more than anything else is a thermometer. Frosting means that the mold is a little too hot.
It does that because the bullet is cooling slowly. The lack of fill out is more likely from too low casting temperature.
Yes you can get the mold too hot with too cool alloy.
P.S. Get a thermometer!

I totally agree. The moment I got my PID, which also gives you a readout of the alloy temperature, casting became a lot easier. My best boolits are also slightly frosted as well.

[DAFzipper]

One other thing to remember is ambient air temperature. Going from winter temperatures to spring and summer temperatures I always have to remember to leave the mould open to cool for a few seconds or I get something like you are talking about. I use that time to do a quick inspection of the bullets I just dropped.

Sent from my SM-T713 using Tapatalk

[psweigle]

I get frosting if I pour too slowly.

[26Charlie]

I sometimes get better results by smoking the mold. I save a few birthday candles for this use. The soot seems to even out the heat flow.

[William Yanda]

"When you pour, do you pile a big puddle over each cavity? You should do that and you should see the center of it "suck in" as the boolit cools and shrinks. That is essential to get good fillout.

The best measure of your mold temperature is the time it takes for the sprue to freeze. It should go from molten and shiny to dull gray in 3 to 6 seconds. If it takes longer the mold it too hot. Shorter, the mold is too cool but it would probably be wrinkling the boolits." David2011

What he said.

[lightman]

A couple of things that I can think of. Lighter fluid leaves behind a little bit of oil. Jewell recommends lighter fluid for cleaning their triggers, stating that it provides enough lube for the trigger. I would give that mold a good scrubbing with Dawn, hot water and an old tooth brush. I use brake cleaner with my iron molds. The other thing I thought was Zinc contamination. Are you pretty good at sorting wheelweights and spotting the Zinc ones. I've never had to add tin to wheelweights to get good fill and I would save that as a last resort.

[Whitespider]

Yes you can get the mold too hot with too cool alloy.

Absolutely true... especially in warm weather.

I feel your pain Bazoo, I've fought with the incomplete fill out with frosted boolits myself (and I'm a ladle caster without a thermometer like you). I seem to have more of that sort of problem using aluminum molds because they're easier to overheat even with an alloy not hot enough.

Anyway, assuming the mold is spotlessly clean without any residue and venting properly, I've come to the conclusion when I see incomplete fill out with frosty appearance I have two problems and I'm making one worse by trying to compensate for the other. The first problem is the alloy is not hot enough (without a thermometer it's easy to get anxious and start dipping before the alloy is up to temp, especially after adding to the pot). Then, in an effort to correct the fill out problem I cast faster to get the mold hotter, and I overheat it (often unevenly, in just local areas of the mold, producing localized frosting).

So here's what I do...

1. I fill the mold, cut the sprue, and set the mold aside with the boolits in it (to help retain heat in the mold)... or I may set the empty mold in my "mold furnace" (a circular saw blade set on an electric burner covered by a cut down coffee can).
2. I sit down and have a smoke (about 10 minutes) and then flux the pot again with sawdust thoroughly stirring and skimming (another 10 minutes or so)... this gives the alloy about 20 minutes to come up to temp, and me some time to reflect on my errors.
3. I set the ladle in the pot and wait about 5 more minutes for it to come up to temp.
4. I fill and dump the mold three times as fast as I can without looking at the boolits (actually dump them in the sprue pile).
5. On the fourth fill I dump and inspect the boolits... typically the fill out problem is gone, and the boolits are slightly frosty (mold is a touch to hot but alloy has come up to temp). If I still have a fill out problem I turn up the heat on the pot and go back to step one.
6. Once the fill out is corrected I begin to adjust my casting rate using the small fan (mounted on the wall, blowing down) I use to blow air over the mold and regulate temperature until the boolits start dropping bright and shinny.

In other words... one thing at a time... I correct the fill out problem before addressing the frosty appearance. The fill out problem is almost always an alloy temperature problem, and there ain't a darn thing I can do about it with "technique"... so that must be corrected first. After that it's just a matter of adjusting technique (or experimenting with technique) to achieve bright, shinny boolits with sharp cornered bases.

However... one thing to keep in mind... sometimes it's just "one-of-those-days" that defies explanation.
I won't keep endlessly frustrating myself if it's "one-of-those-days" where I ain't makin' it happen... some days it's just better to find something else to do and try again tomorrow. It's amazing how the very next day, without changing a single thing from the day before, it all comes together and the boolits pile up.
*

[rintinglen]

One 2 Ounce Zinc WW in the pot can flummox the whole melt, at least if you have a 10 pound pot.. Fill out becomes poor, you crank up the heat until you get excessive frosting and still, you have rounded corners and uneven weights. If you have a clean mold, one that hasn't been oil contaminated, and has given good service in the past, the most likely problem is the alloy. Given that you said that you don't make ingots but rather, smelt in the same pot you cast from, I think this is a thought worth pursuing.
My solution would be to drain the pot, and make ingots out of the melt that remains, then brew up a fresh batch of alloy. I would closely check to make sure that no zinc-ers managed to slip past my previous inspection, and I would flux the heck out of it. If it was casting well, I'd run off a hundred or so good boolits, then I'd add an ingot of my suspect metal. Flux, stir, bring it back up to temperature, then cast up another 100 or so boolits. Carefully inspect the second batch, use a jeweler's loupe or a magnifying glass if you need to. If the second batch shows more examples of rounded corners, curved bands, etc., you will have found the culprit.

However, some days are diamonds and some days are stones.

As has been said, sometimes you do everything right, only it isn't. Taking a break and coming back sometimes fixes "it" without conscious effort.

[gwpercle]

A little tin helps a lot with fill out. I have a box of printers type that is high in tin content and add a strip or two to each pot full.
Frosting will not hurt anything, I tend to cast mine just at frosty .
Keep the zinc out. Beeswax works as a flux, just watch out for flash up, the bursting into flames can be unnerving.
It may be wrong but I also will stick wheel weights into the pot melt them, flux and cast . Being doing it for decades . No harm that I can see .
Gary

[Bazoo]

Thanks everyone. I know that some of you put a lot of effort into answering my query, and I appreciate each answer.

The pot im using is the lee 4 pound pot, and it has as heat control. Its less than 2 years old. It was setting on the covered porch, and got moisture from the air, but wasnt rained on so I assumed it'd be okay.

I have previously used lighter fluid to clean moulds and didnt have any problems that I recall. With the problems im experiencing now, i started with lighter fluid, and switched to brake cleaner to make sure I was getting a good clean.

I am 100% sure I didnt have any zinc as I sorted the bucket by hand, nipping each weight with a pair of dikes before it was put in the good bucket.

It was fairly warm that day, which im sure is why I was getting frosting cause I was keeping the same pace I previously had. I know frosting aint a problem, and I normally keep frosted bullets as long as they are filled out well.

I had not thought about some possible contamination in the pot itself, or the ladle.

As for the amount of sprue puddle, I know it should be fairly large and suck down in the center, But honestly I had forgotten all about it in my frustration and didnt pay it no mind, which of course only compounded my problem.

I've been doing the melt weights flux casting thing instead of making ingots a while because I aint got around to getting all the stuff I need for making ingots until just recently. I should be able to make ingots now, and will do so soon as I can find the time.

I think my problem is that the melt was not hot enough and I was not letting it come back up to temperature properly after adding more. I did use some ingots I had once I got going.

Thanks again for all the replies.

~Bazoo

[beagle]

Okay, here's an answer from left field. How many cavities? It is possible to cast too fast and too hot which will surpass the mould block capability to dissipate heat especially with multiple cavities and large bullets. I've experience this with DC 429421s. This will cause the bullets to frost naturally and also give you incomplete fill out. Try casting a little slower and I even use a small 4" fan directly on the mould for big .458" bullets in small blocks.

Walt Melander at NEI had a computer program that computed all this. Unfortunately, this was lost at his death as I have seen no one mention it since.

I bought a double cavity meehanite mould from him in .375". Different bullet styles. When I was talking with him, he said, "Wait a minute" and did something on the computer, came back and said, "It won't work".
I asked about casting one style at a time and he told me that would work so that's the way we went. Sure enough, try and cast both styles and I got frosting and incomplete fill out.

It has something to do with the mass of the mould block's ability to dissipate heat raised by multiple large cavities (mass of molten lead).

When Petey was on here years and years ago, we experimented with attaching aluminum heat sinks to iron moulds and that helped but made casting very clumsy.

Slow your casting tempo and throw the air flow from a small 4" fan (available from Radio at about $8) on the filled blocks and I think you'll see the problem go away./beagle

[gwpercle]

Thanks everyone. I know that some of you put a lot of effort into answering my query, and I appreciate each answer.

The pot im using is the lee 4 pound pot, and it has as heat control. Its less than 2 years old. It was setting on the covered porch, and got moisture from the air, but wasnt rained on so I assumed it'd be okay.

I have previously used lighter fluid to clean moulds and didnt have any problems that I recall. With the problems im experiencing now, i started with lighter fluid, and switched to brake cleaner to make sure I was getting a good clean.

I am 100% sure I didnt have any zinc as I sorted the bucket by hand, nipping each weight with a pair of dikes before it was put in the good bucket.

It was fairly warm that day, which im sure is why I was getting frosting cause I was keeping the same pace I previously had. I know frosting aint a problem, and I normally keep frosted bullets as long as they are filled out well.

I had not thought about some possible contamination in the pot itself, or the ladle.

As for the amount of sprue puddle, I know it should be fairly large and suck down in the center, But honestly I had forgotten all about it in my frustration and didnt pay it no mind, which of course only compounded my problem.

I've been doing the melt weights flux casting thing instead of making ingots a while because I aint got around to getting all the stuff I need for making ingots until just recently. I should be able to make ingots now, and will do so soon as I can find the time.

I think my problem is that the melt was not hot enough and I was not letting it come back up to temperature properly after adding more. I did use some ingots I had once I got going.

Thanks again for all the replies.

~Bazoo

Do yourself a huge favor and get a Lee Magnum Melter , it will hold an honest 15 pounds of alloy and is so much easier to get a good run of boolits going. I used a small 4 pound Lee melter for years and didn't realize how much of a handicap they are.....it's like trying to run a race with your legs tied at the knees. As soon as the metal is hot and the mold is hot...you run out of metal , stop , add metal , everything cools , you don't get anywhere being handicapped with that 4 pound capacity.
With the big pot , once everything get hot and you can cast until the arms and back give out !
Gary

[Bazoo]

The moulds I was using were all 2 cavity, but when I started having problems I started casting with just 1 cavity trying to rule out one of the cavities as being the root of the problem.

I know that the lee pot aint perfect, but its what I got until I afford a better one. My house burnt down a couple years ago. I had a lee 10 pound bottom pour pot. And when I started back, I was trying to go as cheap as I could with the idea that i'd upgrade certain things later. The pot being one of them. I figure i'll get a bigger pot for normal use, and keep this little one for pure lead which I also cast occasionally.