Help me reduce my rejects please!

[Indiana shooter]

I'm having issues with wrinkles along the parting line usually between the last lube grove and the base of the boolit. I've ran my melt up to 800` and my Sn content up to 6%. I've tried running a fast pace cadence to get slightly frosted boolits but still get these wrinkles but it's only on the parting line. The only thing that seems to work is to stick the spout of the bottom pour in the fill hole and fill it that way but it freezes up my spout every 2 or 3 cycles.

If I had to put a percentage on the rejects I'd have to say 30%. What gives?

[Rizzo]

I'm having issues with wrinkles along the parting line usually between the last lube grove and the base of the boolit. I've ran my melt up to 800` and my Sn content up to 6%. I've tried running a fast pace cadence to get slightly frosted boolits but still get these wrinkles but it's only on the parting line. The only thing that seems to work is to stick the spout of the bottom pour in the fill hole and fill it that way but it freezes up my spout every 2 or 3 cycles.

If I had to put a percentage on the rejects I'd have to say 30%. What gives?

Keeping the mold hot may be the issue.
I have a hot plate that I rest the mold on prior to starting my casting and also when I have to refill the pot or whatever.
FWIW, I use a PID temperature controller for the melting pot and have it set for 725 degrees F.

Are you using at least a thermometer to monitor the temperature or just relying on the melter's knob (rheostat)?

[noisewaterphd]

Ya, if you are sure you are at 800f, and touching the spout causes it to freeze up, then I'd bet my left foot (my favorite foot) your mold is too cold.

What brand mold?

[JSnover]

What are you.casting? Larger blocks take longer to heat up, smaller ones cool more quickly.

[C. Latch]

If I 'fixed' a problem by running 800 degrees and 6% Sn, I wouldn't consider it fixed.

Sounds like a cold mold, a mold with a bit of oil in it, or possibly a poorly vented mold. If the latter, either adjust the sprue plate to be slightly looser, or, you may be able to get away with tapping it (on the handles or a non-marring part of the mold) on the edge of your pot or a wooden block as soon as you fill it each time. That basically forces a tiny bit more metal into the cavity. It has worked well for me with a couple of different molds.

[Indiana shooter]

I am casting a NOE 432-265 RD 2 cavity in the RG configuration. I do use a lyman thermometer. I don't yet have a hot plate so I set the mold on top of my pot to warm it up a bit. When I start casting I pout a very generous puddle and scrap the boolits until it takes an 8 count for the sprue to harden.

I thought that frosted boolits only happen with a hot mold? Several of my boolits are slightly frosted in around the lube groves yet wrinkled where the mold halfs meet.

My casting pace isn't as fast as I run with my lee molds because I have a major sticking issue in one of my cavities. I've tried polishing the mold, running a toothpick around the edges as well as several other techniques i found on here. I've even sent NOE 2 E-mails about it but they haven't replied. (I don't hold it against him I'm sure Al is a busy man)

[Echo]

My bet is on venting. Take a fine jewelers file, or a stone, and hit the top corners on the mold just enough so that you can see a bright line - a couple thousandths will probably do. Top corners on both halves.

[s mac]

I usually cast with a ladle, I have often had fillout problems using the bottom pour spout. Problem solved in my case.

[Rattlesnake Charlie]

Don't overlook some oil contamination. Especially if you lube the sprue plate and/or hinge pin. I would suggest cleaning the problem area with a cotton swab saturated with a degreaser. I use spray type carb cleaner.

[44man]

Go to a ladle, sure fix.

[vzerone]

If I 'fixed' a problem by running 800 degrees and 6% Sn, I wouldn't consider it fixed.

Sounds like a cold mold, a mold with a bit of oil in it, or possibly a poorly vented mold. If the latter, either adjust the sprue plate to be slightly looser, or, you may be able to get away with tapping it (on the handles or a non-marring part of the mold) on the edge of your pot or a wooden block as soon as you fill it each time. That basically forces a tiny bit more metal into the cavity. It has worked well for me with a couple of different molds.

I agree with Latch. Far as I'm concerned you've ruined that alloy with way too much tin. I'm almost to the point where I wish they would ban Tin. Too many casters use too much of it in their alloy.

800 degress is too hot for the pot, unless your thermostat is way wrong. Best to use a good high temp thermometer to see what you alloy temp really is. I agree too your mold is too cold. How long does it take for your sprue to solidly?

[Seeker]

If your mold is clean, I would think it is mold temp. also. I ladle pour and I only have about a years worth of experience but non the less, I've been there. When I first started casting, I was all thumbs with my first 2 cavity mold. After a few times things started coming together and I was making beautiful 200grn rf boolits for my 45 colt. I then purchased some more 2 cavity molds and prepped them and cast more beautiful boolits right from the get go. I'm glad I belonged to this forum because it really helped with the learning process. I then went and acquired a 6 cavity mold and boy was I enlightened. I read how you could use a 6 with a ladle so I didn't even think about a new pot. My first session I poured about 60 boolits and maybe 6 of them were keepers. Right away I was gonna put it up here in the classifieds and find a 2 cavity, but I have never heard of a 2 like this group buy single lube groove 200 gr.swc that drops beautiful, round .454 boolits that size to .452 nice and even around the driving bands. I've used that mold 6 times now and the last time, I poured 250 boolits and sorted through them. I ended up with 245. I'm getting there. Sorry for the long read. What I've learned is mold temp. I thought I had to have the pot hotter, but that didn't really help. Once I got my rhythm, boolits started looking great. I cast at 650°, if I stall for some reason, I dip the mold in the pot for a few seconds and keep going. You gotta keep the mold hot.

[Indiana shooter]

How long does it take for your sprue to solidly?

6-7 seconds


Go to a ladle, sure fix.

I am in the process of getting that set up. The other day my oldest boy killed one of my 4-20 pots (the one that didn't drip dang it) by knocking it off my bench somehow when he was getting his bike out. I figured I would just plug the hole with a screw, take out the bottom pour stuff, get me a bigger ladle and use that pot as a dedicated muzzleloader pot. When I first started casting I used a ladle with a pot that set on my Coleman stove but I couldn't get the bases to fill properly. Well now I know that the small ladle that I had wouldn't hold enough Pb to pour a large enough sprue. Who knows once I get everything set up right I may prefer to hand pour boolits and just switche over the other pot as well.

[castalott]

If you are using bottom pour , try pouring a few where the stream goes exactly thru the sprue hole without touching. This will leave a lot of room for venting. This should tell you if you have a venting problem.

If you are 'pressure pouring' to fill the cavity, guess when the cavity is full ( you can get very accurate with this) and then move the mold down away from the spout and pour the sprue without changing the flow until you shut it off. Don't wait until the boolet is hard & then try to pour the sprue. One pour works for me like that.

I think I would 'flux' the pour very well indeed. I use a soldering paste that makes the stream flow like water. The smoke off of it is flammable so I keep a propane torch handy to start the burn.

It does sound like the cavity has oil or something in it although I have molds that have imperfections on the boolets like that until you find the 'correct' casting technique.

I like to loosen the bolts on the sprue plate until the sprue plate swings of its own weight. ( Not for Lee molds.) If I am ladle casting, I use the ladle to hold pressure down on the mold to keep it from swinging until one cavity is full and set. ( Yes , this can be done.) Then do the others.

Some molds do not fill completely because of 'swirl' or I assume 'trapped air' at one point in the mold. It is frustrating to have perfect boolets each time except for ONE spot .Some mechanism is keeping that one spot from filing correctly. But what is it?

Does the mold have a defect in metal that either stays too cold, moves heat fast to another area, or holds some contamination? Does the fill technique produce swirls that won't fill consistently? I don't know but I would like to.

I would try pressure pouring with a ladle.

[Blackwater]

The hardest thing I ever had to learn was what temps the mold and metal needed to be when I was starting out. I still sometimes struggle with it. And I was learning by simple trial and effort, and that took a while. Every time I heated up the pot, I was experimenting and trying to learn something. It was a simple matter to speed up or slow down my pace to see what the effect was, and to adjust the temp controls on the pot. I doubt that there's really any way to learn casting from a book or advice given here, but it sure helps narrow down your parameters and get to good bullets quicker, so it's a real asset. But in the final analysis, we've just got to learn to pay attention to the "little things" while we're doing our casting, and note the effects of time, temps of mold and metal, and the results, and just learn to go with what works with our metal, our pot and our mold. If I learned it mostly on my own, anyone ought to be able to learn to cast good bullets, especially with the insights available here, but even then, it still takes learning to observe what's going on and make adjustments as we go. If there's any other way, really, I don't know about it. There are generalities, but when we get down to casting with a specific pot, a specific mold and a specific lot of metal, it's all about observing and adjusting as we go.

If bullets aren't filling out, we need higher temps, a little more tin, or a faster pace in casting. If the sprues are taking too long to solidify, we need to slow our pace down a mite, or turn the pot down, or maybe both.

When I first got my Lee Magnum Melter, I had to learn to turn the thermostat down as the level of the metal in it dropped with casting, or I'd have to slow my casting pace, and even that didn't always work well enough for me.

Basically, the best thing any caster can do is learn to observe and adjust as we cast. There is no real forumla other than this, but generalities DO help understand what to do as we observe results of what we're doing, and let us know how to adjust that to get better results and better bullets.

[bangerjim]

"warming it up a bit" is totally unacceptable for casting good boolits. Setting a mold on the edge of a lead pot is what they did in the dark ages. Go out and buy a hotplate, heat your molds up to FULL casting temp, not warm! I do that and get PERFECT drops from the 1st one everytime with a Lee 4-20 bottom pour running at the appropriate temp for the alloy I am using.

You do not need a PID controller to drop perfect boolits. I have been doing it for years without one. A fully hot mold is your leeeeeetle friend.....preheated on a hotplate. A hotplate, today, is as important to a serious caster as alloy, a lead pot, and molds.

You are totally wasting Sn at 6%! 2% is all that is needed for good fill. Unless you have several hundreds of pounds of Sn, like I do, you need to address what is wrong with what you are doing and quit wasting a very expensive metal. Probably all temp related.

Oil and grease do NOT cause wrinkles. Cold molds cause wrinkles. I have never "de-greased" a new mold.....ever. And I have many many dozens of them, all casting and dropping perfect boolits from the 1st one because I preheat (NOT just warm up) the molds as described above.

bangerjim

[gwpercle]

Go to a ladle, sure fix.

Get a ladle with a side spout, not the open spoon thing. Fill the ladle, put the nozzle against the hole and turn up right. Pressure casting.
I turned in a bottom pour pot and got a Lee Magnum
Melter and ladle after making piles of rejects and very few nearly perfect keepers. The ladle seems to work better with double cavity moulds. At least for me it works better.
Keep trying, casting has a nice big learning curve, it's an art, science , and you need some black-magic and voo-doo at times. Don't forget to hold your mouth right when casting. That helps.
Gary

[Mica_Hiebert]

mould is too cold.

[country gent]

If the mould is new and this has always been a problem check the vent lines. sometimes they are closed off with perservatives or other things from manufacturing processes. Also ocassionally they just may not get cut deep enough.With a sharp scibe Awl or ice pick lightly draw it thru the vent lines from cavity to edge and see what is removed. Those vent lines are shallow it dosnt take much to plug them. Ligtly breaking the top edges of the blocks may help also. A sharp scribe lightly drawn thru the vent lines will clear them. you may see a light dust or crud, Could be burnt oil or wax sometimes a medium to heavy smoking may plug them.

[JohnH]

Over the last year or so I've bought two NOE molds and love them both, but... you gotta follow the break in instructions, and most definitely have to smoke the mold prior to casting. When I first ran my newest mold a 4 cavity 30 caliber 200 grain mold, I failed to smoke the mold and got exactly the result you describe. Got out the trusty BIC and blacked those mold cavities and made a tad over 600 boolits before I stopped. Not sure why aluminum needs this, I've never had to smoke an iron mold, but at least half my aluminum molds need it, a couple even need touching up during the casting process.

[bangerjim]

True. I have always found I need to smoke Al molds (ONLY) the 1st time. Been doing it for years with excellent success. That very thin carbon layer helps in release. Without it, I saw slight hanging and sticking. I use a beeswax candle only, (and light with a BIC lighter!!!) as it gives excellent ultra fine smoke, similar to a lazy acetylene flame.

NO SMOKE for steel/iron/brass molds needed.

banger

[Priusron]

I use a hot plate to heat my mold. I put a saw blade on the hot plate. My mold is a hp mold so has the pins sticking out the bottom. It won't sit flat on the saw blade. I place it flat on the spur plate. I have a can that I cut 1/3 off of and sit that over the mold. I turn the hot plate on high and let it warm. I set my put on 750 with a Pid. I am new to this and I can throw bullets all day with this setup with very few rejects.

[Rattlesnake Charlie]

Ahhhhhh. So many different techniques that work for so many different casters. Science, craftsmanship, black magic, and artistical talent. They all have a place in boolit casting.

[TXGunNut]

I'm guessing this is a new mould. I nowadays give them a good scrubbing with hot water, dish soap and a tooth brush. Then I generally do it again. Then I heat cycle the mould at least three times on the hot plate, letting it cool each time. Then I check sprue plate fit to make sure it fits tight but not too tight. That said, I'll agree that it sounds like your mould was likely too cold. Another thing; sometimes a mould just needs a session or two to break in. I won't pretend to know why that is but when things aren't going well with a new mould after several attempts in the first sessions I put it aside and go on to the next one. After a few sessions it's either broken in or I've finally figured out what it likes, I honestly don't know.

[Le Loup Solitaire]

Thirty percent is too high. Assuming that the mold is squeaky clean with no trace of oil or other petroleum based product, then start with the right temperature (high enough) and 1-2% tin in the alloy. It is not necessary to pressure cast with the spout tight against the sprue hole; a properly regulated stream is sufficient..not a fat oversized one as that will interfere with the air that has to get out of the cavity(ies). Make sure that a generous amount of alloy sits on the sprue plate to feed the shrinkage and not cause voids. A couple of tricks that might be worth trying; 1) drop the mold (when full) about an inch onto a lead ingot placed below the mold....the "jolt" will cause a downward pressure for the molten alloy to fill any voids/bubbles. 2) some casters run the mold back for a second "pour" while the sprue is still molten. These gimmicks take a little practice as they can be kind of sloppy at first, but there is a good chance they can cut down on defects. LLS

[CASTING MACHINE]

Way to high of a temperature for casting. Find a way to make this work at 660-675 f. Are you seeing excess dros in your pot. Constant fluxing and skimming. Keep the heat down and ventilate well you will live longer. I have read somewhere on this site, again i maybe wrong, at that temperature you maybe scorching your tin as well as causing lead alloy to release toxic fumes that at lower temps would not occur. Not sure what elements they were but go to the area and read, really read it through. Read the discussions before you proceed.
When you cast with a high heat, high tin content and use the so called pressure poor method described you are literally forcing alloy the into the venting lines and the parting line. Hence the troubles. LEAD INSIDE MOLD HALVES ETC. Better to have a hot mold with occasional frosting than have all those rejects.

[shoot-n-lead]

Help me reduce my rejects please!
Sure, I certainly will...send them to me and I will shoot them.