casting trouble

[holsterguy]

Hi guys. First post time posting here so bear with me. Whenever I cast any bullet no matter what mold, size, shape or anything I get really lousy bullets until everything gets so hot that the bullets are coming out frosted. And even then only sometimes are they really good. (Sometimes cast 50 and throw away 20 or 30). Any ideas? Is it possible when smelting my ww that I skimmed off all the "good stuff"?

[Mica_Hiebert]

Nothing wrong with frosted bullets allot of times that's what you get once your mould is hot enough to fill out... you can try adding more tin to your mix and running the lead temp a little cooler if you want pretty shiny bullets but why?

[reddog81]

I try to cast as quickly as possible until the mold heats up and then dial it back a bit. Out of the first 50 bullets I cast half are probably thrown back but by then everything should be good to go and 90% or more are keepers

[Mica_Hiebert]

Pre heat your mold with a hot plate and if your running a 6 cavity start off filling only one cavity until it's making a good bullet then 2 until it's good and the 3 and so on until you have worked up to your 6th cavity. When I cast I just drop my bullets back into the pot until I get good ones but I pre heat my mould on the wood stove and it rarely takes more than a couple of pours before I'm in bussiness.

[noisewaterphd]

I think it would be helpful to talk about one of your molds specifically, and go from there.

Until then:

1. Try adding a bit of tin if you are unsure of your alloy. Heck, maybe even buy a few pounds of #2 to start with from somewhere like Rotometals. At least that way you can take the alloy out of the equation.

2. Have you cleaned the molds? I mean really, really cleaned the molds? Are these new molds? Aluminum? Iron? Brass?

3. Keep the molds nice and hot, lower your allow temp.


At the numbers you are talking about (around 80 bullets), depending on the mold, you might have barely got the thing to operating temperature if you didn't preheat the mold.

[JSnover]

What does "really lousy" look like? Are they wrinkled or are they not filled out?

[country gent]

Several things to look at here, you dont give alloy ( lead antimony tin ww or what it is), pot temp ( perferrably measured with a thermometer for such), moulds prep ( cleaning, pre heat lubrication) or style of casting ( bottom pour or ladle). As to your alloy for most around 700-750* is adequate for casting. Mould pre heat can make a big diffrence as to getting good bullets quickly. Oil or lubes in the cavitied can take a long time to "burn" out. Fill rate is important also a fast fill helps keep mould hot and material molten thru the complete fill. Sprue plate fit and tension can cause base issues. Start out clean mould with toothb brush and dish soap water mix and allow to dry. Check vent lines to insure they are clear and not pluged off. This can be done by pulling a sharp scribe awl ice pick or exacto knife thru them from cavity to outside edges. Pre heat to 350*-400* on a hot plate or on top of the pot. Very lightly lube sprue bolt alighnment pins and hinge with 2 cycle motor oil. Make sure allot is clean and fluxed up to temp. start casting with a fast fill and quick pace. Small bullets in large blocks may take awhile to cast good bullets as mould mass is higher to heat up. Alloy running to hot may heat mould to to high a temp causing frosting. You may need to experiment a little to get moulds to perform also

[longbow]

I'll go with pre-heat the mould and cast at a steady quick cadence. It doesn't do any good to have the alloy really hot but cast so slow the mould stays cool.

I pre-heat until the sprue plate lube started to smoke... just starts to smoke.

+1 with nothing wrong with frosted boolits. I couldn't care less and generally aim for slightly frosted boolits as I get better fill out without adding tin.

And yeah, have you cleaned the moulds?

Also, poor venting can cause fill out problems. I often use a diamond grit sharpening stone to take the top edge off the mould blocks where they meet under the sprue plate to provide better venting for bases. This is an extremely small bevel.

Loosening your sprue plate is another trick that often works if bases are not filling out properly. My sprue plates will almost swing free. If the sprue plate is tight to open and close it is too tight and will hamper venting.

Also, flux often or at least often enough that there is no dross or skin on the alloy. Fluxing will mix in the "good stuff" not remove it. Simply skimming may remove tin.

Where are they not filling out ~ bases, driving bands, on one side, noses?

A bit more detail would help us analyze your problem.

Longbow

[jcren]

Hotter mold. A $15 dollar store hot plate works great. Most folks, myself included, keep cranking up furnace temp due to cold mold wrinkling, then when the mold finally heats up, the melt is too hot.

[Le Loup Solitaire]

Adding a bit of tin usually 1-2% will improve the "flowability" of the alloy. As pointed out the adjustment of the sprue plate will effect the venting of air from the cavity. The plate should sit flat on top of the blocks but not sloppy up and down; it should swing on its own weight when the blocks are tilted. Another factor to consider is the width of the pour stream... if it swamps the pour hole then it will also prevent or hinder the escape of air from the cavity(ies). A good size sprue puddle is necessary to feed the bullet and allow for shrinkage, otherwise you can get voids in the bullet. Frosting has absolutely no effect on accuracy...if the appearance is annoying then you can polish the frost off with some #0000 steel wool. Overheating the alloy/mold becomes evident when the sprue takes too long to set up...then its time to cut back on the heat or slow down. A small fan blowing air across the blocks/casting area helps. LLS

[MUSTANG]

Are the molds well cleaned of any traces of oil? Use acetone and a tooth brush to scrub themolds out several times and then give them another try. Also, try smoking the mold cavities very lightly with a candle or other light smoking flame if problems persist.. Or, as an alternate try a spray like :

http://www.midwayusa.com/product/763758/frankford-arsenal-drop-out-bullet-mold-release-agent-and-lube-6-oz-aerosol

Keep after it and you'll see progress combining the variety of suggestions given in this thread.

[David2011]

Holsterguy, welcome to CastBoolits!

Enormous amount of excellent advice here. Wrinkled boolits are because the mold is cold. Frosted is because the mold is up to temp but casting too fast bit lightly frosted is sufficiently close to PERFECT. The melt MIGHT be a little hot bit not much. Lower the melt temp a little and slow the casting pace a little. You should be able to cast 3-4 times a minute. You control the mold temperature u how fast you cast. If the puddle on the sprue plate takes more than 3-4 seconds to freeze the mold is too hot so slow down until you get the 3-4 second freeze time. A solid surface hot plate is an excellent investment.

David

[Cherokee]

You have gotten good advice so I'll just encourage you to keep at it, practice will help.

[Hickok]

All good information!

If you can't find an easy scource for tin, go to the hardware store, look for solder, and then pick a roll with the highest tin content, (they differ as to tin/lead ratio). It is pricey, but adding the tin to your alloy really helps the boolits fill out.

Not a perfect solution for getting tin, but it will help your boolits. This isn't precise by any means (Guys, don't tear me to pieces)), just unroll some wire solder and throw in the pot and see if it helps.

[rintinglen]

Pre heat your mold with a hot plate and if your running a 6 cavity start off filling only one cavity until it's making a good bullet then 2 until it's good and the 3 and so on until you have worked up to your 6th cavity. When I cast I just drop my bullets back into the pot until I get good ones but I pre heat my mould on the wood stove and it rarely takes more than a couple of pours before I'm in bussiness.
This!!!
the best tip I ever got was to pre-heat my molds before attempting to cast. Whether you go the hot plate route, a wood stove, or just rest the mold on top of the lead pot, pre-heating the mold is essential to getting good bullets before the cows come home. I have a 311-466 that I nearly gave up on, because it took so long to get it up to temperature. Once I started preheating the mold, it began to drop excellent boolits.
Don't worry about the frosting. I can not cast good boolits from LEE molds unless they are mildly frosted. They shoot just as well as other molds's products that are shiny.

[Victor N TN]

NOTHING wrong with a frosted bullet.

[Ola]

NOTHING wrong with a frosted bullet.
Agreed. In some cases "Only good bullet is a frosted bullet"

[shaggybull]

Sounds like your spur plate is not hot enough. I was having same problem. Cured it by preheating molds on hot plate. Check in the casting section there is a sticky where you can download a book called From ingot to target, the book addresses this issue. It helped me.

[Driver man]

I dip a corner of the mold into the mix and when the lead flows off the mold it is up to temperature. Lightly frosted is what I like. Constant stirring of the lead to keep the alloy even and occasionally refluxing helps. Practice makes perfect.

[holsterguy]

Hey guys. Really appreciate all the responses and help.
As far as cleaning yeah, cleaned real good with brake parts cleaner and old toothbrush. Followed Lee's instructions very carefully.
By bad looking, it's mostly bands not filling out. Sometimes base,sometimes both. I'll try all your suggestions and see what happens.

[holsterguy]

Oh yeah. Almost all my molds are Lee 2 cav.

[CHeatermk3]

Welcome to the forums holsterguy---I'm a relative newby to casting my own but I do not think that brake parts cleaner is good for cleaning your aluminum molds. Better is hot water and dish detergent like Dawn. Scrub/rinse/repeat finish by heating in boiling water, quick wipe and the water will evaporate off the warm metal pretty quickly.

For me, lubing the alignment pins and sprueplate created a nightmare situation until I learned how very very VERY little it took to be too much and lube in the cavities is sure to produce frustration.

Are you ladling or bottom-pouring? I'm having good results using a Lyman rowell ladle that was giving me problems until a friend showed me his, which he'd had to polish up (on the inside of the hole the metal flows through, and the outer edge of the hole or "spout" where it comes out).

Good luck!

[44man]

Good info from all but if bands do not fill on a TL boolit, you are TOO HOT!
I don't like frosted boolits. Once too hot, your boolits will be more out of round and smaller in diameter. Mold expansion needs to be understood.