mold temps

[armyrat1970]

Any of you guys ever check the temps of your molds to see what range you have to start casting with or when it is just to hot? If so how? Understand the hot plate if that heats the mold but what would be the actual temp of the mold? Different alloys made need a hotter or colder mold. Have another thermometer and was thinking of heating my mold and closing the blocks on it to check the temps before casting to see how hot the molds were and see at what temp they started dropping nice boolits. And when the molds got to hot checking the temps again and let it cool down before casting again.
Maybe I'm just thinking to much and making this more difficult than it really is.:)

[Slow Elk 45/70]

Hullo Armyrat, when I start my pot heating up , I like to put my molds on the hotplate and let them warm up at the same time. You will have to play with the temp to get what works best , depending on the kind of molds you are using , aluminum wants more heat than steel.

Mark your setting on the hotplate dial when you get what you need, with preheated molds that are hot enough, you should not have to dump more than a couple of casts as rejects, if any. As long as your alloy is 700-800*, at least this works for me.

I don't think you need to do the extra steps of trying to measure temp of your molds with a thermometer, unless you just want to. Some people use the infrared heat guns to check their molds, just depends on how technical you want to get. A little time spent working this out is time well spent. It ain't rocket science...have some fun

[Bret4207]

There was an article several years back about a guy who put an electronic temp probe in his moulds to try and do what you're thinking of. IIRC it wasn't effective or particularly efficient what with wires hanging out and what not. While I agree with your concern and interest, I think this is the "art" part of casting- that feeling for when you "know" it's about right.

[Pat I.]

Maybe I'm just thinking to much and making this more difficult than it really is.:)

With the above sentence you just discovered the biggest secret of bullet casting.

The moulds hot enough when it's throwing good bullets and too hot when it melts or you can go eat dinner waiting for the sprue to harden.

[243winxb]

Maybe I'm just thinking to much and making this more difficult than it really is Yes , over thinking casting. Just turn pot to highest temperature, keep casting till you get good bullets. Turn pot temperature down to when experences tells you to set it. No need to know the actual temperature . Wrinkled/not filled out bullets may not be mould temperature, oil/dirty mould will do same. When you just start casting, you will do 2 things, burn off any oil/dirt and heat the mould evenly, not hot spotting it on a heating element.

[armyrat1970]

With the above sentence you just discovered the biggest secret of bullet casting.

The moulds hot enough when it's throwing good bullets and too hot when it melts or you can go eat dinner waiting for the sprue to harden.

Yeah. I think you guys just answered my question. Sometimes I just think to much and make simple things to complicated. I always just cast and drop my boolits. If the mold is to cold I will just throw them back in and continue until I get a good one and then just roll with it until the mold gets to hot. Then I set it on the side and take a smoke break giving it a few minutes to cool down. By that time I can start casting again.

[Pat I.]

I use a thermometer in my pot because I weigh sort my bullets and find keeping an eye on the temperature cuts down on the variance. To preheat my moulds, either aluminum or iron, I stick the front corner in the pot for a 30 or 40 count and go to it. The first couple of casts might be a little cold or hot depending on the mould but after that it's full steam ahead. I tried different ways of preheating but got tired of throwing 30 casts away waiting for the mould to heat up. This is a lot easier and faster and doesn't hurt a thing.

[deltaenterprizes]

I checked mine one day with a pyrometer and when it was throwing good bullets the mold (iron) was 350*

[Shiloh]

As stated above by Bret, that is where the "Art" comes in.

It should be the same if using lead from a particular alloyed and smelted batch. There may be a very small shift due to atmospheric conditions, ambient temp, humidity, ect. This is if one is casting outside or in the garage like me.

My mold and alloy temp varies as I have been using up a lot of assorted scrap lately. I have been playing with heat . Some lower tin alloys cast better at higher temperatures.

Shiloh

[armyrat1970]

As stated above by Bret, that is where the "Art" comes in.

It should be the same if using lead from a particular alloyed and smelted batch. There may be a very small shift due to atmospheric conditions, ambient temp, humidity, ect. This is if one is casting outside or in the garage like me.

Mine mold and alloy temp varies as I have been using up a lot of assorted scrap lately. I have been playing with heat . Some lower tin alloys cast better at higher temperatures.

Shiloh

And I am sure when casting in a garage you have proper ventilation.:)

[243winxb]

To preheat my moulds, either aluminum or iron, I stick the front corner in the pot for a 30 or 40 count and go to it. Lee, its OK, But not for iron moulds. From Lyman Bullet Making Guide-
Never dip your cool mould into molten bullet metal because the rapid temperature change may cause permanent block warpage. From Ohaus guide to better bullet making -
Never submerse the blocks into the molten alloy.

[Nora]

If you've really got to know maybe you could try one of these for the mold temp. http://www.instrumart.com/Product.aspx?ProductID=28613

[243winxb]

The model 86269 infrared thermometer utilizes an 8:1 distance-to-spot ratio meaning it measures a 1" spot when held 8" from the target. Ok, someone buy one and shoot some hot bullets leaving the mould on there way down water dropping. I bet there is a wide difference in temperature.

[Pat I.]

The only aluminum moulds I have are LBT but I've been sticking the corner of my iron moulds in the pot for years without a problem. Lead on the outside or lead on the inside, what difference would it make? I imagine if you were casting over a bonfire in broad daylight and got the melt up over 1000 degrees it could cause a problem but otherwise it doesn't.

[jdgabbard]

You mean there is such a thing as too much heat??? I've never seen it with any alloy. But I have seen what happens when its too cold.

[Nora]

You mean there is such a thing as too much heat??? I've never seen it with any alloy.

Lead boils at 3180* F. If you hit that, Id say then it would be to hot for good casting. :shock:

Nora

[jdgabbard]

Lead boils at 3180* F. If you hit that, Id say then it would be to hot for good casting. :shock:

Nora

My lead boils all the time when I stir it with my wooden stick. :shock:

[rugerman1]

My lead boils all the time when I stir it with my wooden stick. :shock:

Thats the moisture in the wooden stick trying to make a tinsel fairy.:!:

[kamikaze1a]

I've only been casting for about a year but this is what I do...I warmup my Lee Aluminum molds over a small propane camp stove. I hold the mold by it's handles and rotate it over the flame like roasting a hotdog. Then make a pour, cut the sprue almost immediately and then let the boo's sit in the mold for an extra long time. After a couple of pours, mold is hot and I start pouring in earnest.

As a side note, I am using a Lee bottom pour and I used to have quite a wait for the lead to melt even when set to high. I now use a propane torch to melt the lead as it sits in the pot. I try my best to heat the lead rather than the pot and that cuts my melt time to like 5-10 minutes.