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boatmanz2003

problem pouring large lead weights

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hello, i have a alum mold 16 oz inline mold,when i pour the lead form bottom pot, its flow isnt great enough, so i used 1.5 lb ladle could not get enough lead into mould,so i went too larger pot and ladle, the weight comes out of mould with a sunken depression in center or mostly near sprue hole i am getting the pour filled to the brim including sprue channel also had same problem with 10-15oz in line weight pours in a cast iron mould(,my cannon ball moulds to 20 oz come out perfect), i heated mould, i candle blacked mould, increased heat,increased ladle size,waited for remelt of sprue additions to pot to no avail,( im using shotgun shot for my lead source) only thing i can think of is grind sprue inlet larger? or change lead type? any suggestions? thanks!

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I've had the same problem, I was pouring 1-1/2 oz shad heads with soft lead, with a RCBS melting pot, and it would have a crater in the side of the shad head. I lowered my melting pot temp and I think it helps, but I'm not sure. I don't think I tried a ladel.

I pour lots of 10 through 16 oz Bank Sinkers with a ladel, with soft lead and don't have any trouble with those except I do have a little trouble with the 6 oz, it craters a hole down through the spru, so when you cut off the spru there is a hole down through the bank sinker.

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I've had the same problem' date=' I was pouring 1-1/2 oz shad heads with soft lead, with a RCBS melting pot, and it would have a crater in the side of the shad head. I lowered my melting pot temp and I think it helps, but I'm not sure. I don't think I tried a ladel.

I pour lots of 10 through 16 oz Bank Sinkers with a ladel, with soft lead and don't have any trouble with those except I do have a little trouble with the 6 oz, it craters a hole down through the spru, so when you cut off the spru there is a hole down through the bank sinker.[/quote']

Heat the molds up and put some fine air escape lines. You can do this by using the edge of a flat file. It sounds as if there is some trapped air, cooling too fast, or both.

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Try holding your mold at a slight angle. I have a couple of molds that do this also. By tilting the mold they pour fine. You might find other tips in the wire baits forum, that's where most us lead head's hang out.

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Pre-heat the mold more.

I pour the same (but changed)type mold from 2 plamer hot pots.

I only heat enuff in the pot to be just more than the amount needed for the pour.

I let the mold sit on top through heating, and pour a few warm up pours before trying for the good ones.

I run harder lead, have made the gate larger.

No blackening , I polish my molds.

And I make shure I pour extra in to the gate.

I pour it tilted.

Once going they all come out fine, no shrink, or air pockets.

Your lead is going to shrink in the mold as much as it shrinks in the pot, as it cools.

If you get the mixture to no shrink in the pot, it will also not shrink in the mold.

Good soft /near pure lead shrinks a lot.

Harder lead will help, but you have to get it hotter to pour right.

But once you get it right they will all come out.

Also do it out side using the propane turkey fryer to heat 20lbs and a larger ladle.

Then the volume is there to keep pouring them.

Hope this helps.

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Richoc,

How do you polish your molds as stated above? Do you use polishing compound you get at the auto parrts store? Do you use a dremeal or do ya do it by hand?

thanks monty

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What I do is 2 different things.

Polish with diamond polish and a dremal type tool.

This works great, do it on the pour gates also.

Increase the angle of it funnel and it will get the lead it there.

I have not made it any larger, where it meets the weight.

The smoother the gate is the better the pour flows in.

Some of my jigs look like chrome right out of the polished molds.

Worked in a plastic mold plant for 3 years and learned alot there that helps with the lead molding.

Then some times I candle carbon the molds .(hate to do this)

But this is sucksville for painting.

So then I polish the carbon, off with paper towel ,Q-tips and dremal

tools.

This works and doesn't leave a film on the lead, this way.

No blacking to your hands and work area either.

But venting this mold helped it pour greatly.

I have the do-it 16oz inline.

On the end that would be at the handle I have channeled a 16th in vent out , in the eye ring area to the outside of the mold.

I pour this mold hot, and angled with the handles up.

Warm it up on the pot as you melt.

I pour hard lead for this and run 2 laydle type pots.(plamers)

The trick is to run 2 lbs of lead in there 2 get it good and hot.

And I can pour it with control.

I pour these while working on other stuff.

If I need a lot of them quick I heat the lead on propane turkey fryer

And get it good and hot and just go for it.

Watch not to over heat the mold.

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Looks like you have all kinds of things to try. It's a bummer when the lead won't fill the cavity.

I would try to make the hole a little larger with a dremel and make sure the lead is hot. Pour a couple, 3 or 4 if needed w/o the hook to get the mold hot. Be quick when pulling the test lead out of the mold and pour again. The first couple may not be complete. That's because it's not hot enough. Keep pouring until it comes out right and then slip in the hook and go for the good one.

Just for reasons like that a lead pot is better then the ladle. Good luck and do be careful with that stuff. It leaves a nasty burn if it finds your skin. As they say, been there done that. :rolleyes:

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i use a portable burner you can get at wall-mart. it works great to heat up the mold before ya pore. on bigger weights i keep the mold right on the burner as i pore the lead. Works Great!!!!

monty

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A couple of things to try:

Heat your molds up real good before pouring, I use a hand held propane torch for some of mine. Get the inside hot!

Try adding some tin to your lead to harden it up, a fellow gunsmith taught me this one and it works fabulously...makes the lead shrink a whole lot less and wont oxidize as fast either.

I like to blacken a mold with the smoke from kitchen matches, this makes a HUGE difference. Alot of people use candles but in my opinon the kitchen matches are more "soot'ier" if that even makes sense.

Polishing the mold is a great tip, if you use a dremel (or foredom) you would be shocked what a little polishing compound will do for you....also try hitting your gates off with some 1000 grit sandpaper.

Skip the ladle, you need to pouring straight from the pot if able.

Hope it helps, JIM

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When I say ladle, it is the hotpot it self that is the ladle.

You really got to pour it in there fast and smooth also.

You will never be able to pour this mold with any bottom pour

that I have ever seen.

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Thats what I figured you meant Richoc, you have sure been around melting pot and back...Since I only use my hotpot for pouring lead into molds (got a cast iron pot and a fishfryer for cleaing wheel weights to pour ingots with) I tend to think we all use hotpots and have never even used a bottom pour. Like you I run my hotpot 1/2 full and pour directly from it 90% of the time. In fact I have never poured into a cavity as large as 16oz either :lol: but I wanna think your suggestions about enlarging the gates, running harder lead and venting the molds will fix this even with a bottom pour...Keep us posted, boatmanz2003.

JIM

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i use a turkey frier to melt used tire weights as well, but what i found that really works well to make ingots is to get a big stainless steel soup ladel and a teflon coated mini muffin pan that has 24 cups. you can make alot of ingots fast this way. just an easier way to get a boring job done faster.

monty

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hello all , thanks for your suggestions, heres what i have done to solve the problem thus far,i resmoked mold, tilted mold, enlarged sprue hole, used edge of file to create vent hole to about 1/8 by1/16,and heres one thing i know was causing problems, i didnt keep ladle hot!! lead was starting to set before pouring, also i noticed if i slowed down the pour near the almost full to sprue hole, the extra amount allowed for some of the reduction in size to be curtailed some what,but i still have the same problem ,some pours better but in no order of pouring(that is no matter what temp of mold is warm to hot hot, so i think it may be the lack of tin?? anybody think of anthing else to look for?

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You could never get this mold to work with any bottom pour I have seen.

The gayte would need to be at least a 1/2 in dia. hole.

Ok, here is the final fix to pouring that mold.

You must dump it in there and fast and steady, and just over pour the gate.

Let it run down the top of the mold away from you.

If it gets in the hindge area , pick it out with pleirs before trying to open the mold.

Remember the surface is just flash setting the core can still be melted when you set it to cool.

If your lead mixture shrinks when cooling in the pot , the same percentage is how much shrink you will in the volume of the mold cavity.

Getting the lead mixed right so it doesn't have the sink hole in the pot will be a good way to know you have it right.

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try preheating your mold before pouring place it on top of your lead pot also are you useing pure lead if so try mixing in some wheel weights the generaly give these away at any tire store. Also you can hold the mold over a candle and let it smoke the cavity this improves pouring greatly.

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