Question about Cast Iron Pots for Smelting/Alloy Mixing

[Jeff82]

So, I've got this 1500 watt hotplate that I use to heat my molds and thought I'd try it out for smelting and mixing alloys. I measured the base of the burner (8-inches), and decided to find a cast iron skillet with side pouring spouts and an 8-inch base. I tried melting small amounts of lead (3-lbs) and it worked great. When I tried melting 10+ lbs, it all melted, but lead would cool and accumulate on the edges of the skillet. I can work around this, but it isn't too efficient.

I noticed that RCBS and Lyman pots are smaller and the sides are straight up and down. They also have minimal handles. Then I looked at the design of my furnace. It's designed as a narrow cylinder; small surface area, straight side walls.
It also is only 500 watts.

I'm guessing that what I really need is a cast iron pot with low surface area to avoid heat loss and not much of a handle to reduce the tendency of the pot to act as a heat sink.

Anybody have some advice on this? I think the 1500 watt hotplate should produce enough heat, but that I need a pot that is smaller and more efficiently designed.

Thanks for your input!

[RayinNH]

Personally I think you'll want more heat. The hot plate might work initially, but if you get as crazy about this stuff as we all do you will soon want a much bigger pot and hence the need for more heat. The hot plate with a small pot will work fine for casting but not smelting. Think Tim "The Toolman" Taylor, you need more horsepower :D...Ray

[David2011]

Hi Jeff,

Welcome to the forum. You've figured out the pot shape. One of the commercial pots would work much better but they only hold 10 pounds of molten metal. That's pretty small, especially for smelting. Your 500 watt furnace has the heating coil wrapped around the base of the reservoir and probably has some insulation around it to keep the heat from going in unintended directions so it's more efficient for the watts consumed.

What are you trying to do? Are you melting clean alloy for casting boolits or smelting scrap lead to make ingots? Smelting in such small quantities would be an awful lot of work. The skillet has lots of challenges. Your skillet will probably hold 30-40 pounds of molten metal. The hot plate may not be suited to support that much weight. You don't want to try to pick it up by the handle full of molten metal. It will slosh out and at the best case, making a mess that's hard to clean up. Worst case it ends up on people. In any case, even without the cooling around the edges, it sounds pretty dangerous. If you haven't seen the "Badly Burned" Sticky, please read it. http://www.castboolits.gunloads.com/showthread.php?t=51265

Some people use a Coleman camp stove as a heat source. Others use a turkey frier/ Cajun Cooker as the heat source. It takes a lot of heat to smelt. There is a wealth of information in the Casting Equipment Sticky section at the top of this section.

If you're smelting you may need more heat and a bigger pot. I use a Cajun Cooker and a Harbor Freight cast iron Dutch oven to smelt and find it adequate. If you're casting boolits you might be happier in the long run with an electric pot that's big enough for your needs. Dipping with a ladle or using a bottom pour is a whole separate discussion and could be influenced by the type of boolit you want to make.

Safety considerations:

Only use cast iron or heavy stainless steel containers for melting lead. If you fabricate your own, carbon steel is safe. Aluminum can fail without warning.

The heat source has to be able to support the weight involved. A 12" Dutch oven can weigh 140-150 pounds when filled with molten lead.

Once used for melting lead, a cooking container can never be cleaned up enough to use for cooking again.

David

[Jeff82]

Here's the thing with me. I've really got a small scale operation. I produce about 250 bullets at a time to support my trips to the range every three to four weeks. My little 4-lb pot has served well for this, but a larger pot would be more efficient. Still, I've cast thousands of rounds this way.

The crux of the matter is that I want to mix alloys and form them into ingots prior to casting. This would also be a good time to do some fluxing and cleaning. Right now I've got about 30-lb of lead that I want to mix with linotype. The hot plate with small pot idea would work OK, since I really only want to mix 10-lb at a time, and would like to be able to pour directly into the ingot mould. I'm really looking at this as an alternative to buying a 10 or 20 lb furnace.

Anyway, sounds like my hotplate just isn't enough. The thing is that my total lead/alloy usage is only about 60 lbs a year. So, it's a small scale thing. The ability to smelt would be a modest plus.

[Guesser]

I've been using an old Ideal cast iron 10 pound pot on a 1500 watt hot plate since 1979, works great for casting with a dipper or mixing small batches of alloy.

[Casting Timmy]

I wonder if a little insulation could help you out with the hot plate. I still want to find a large truck drum to go over my dutch oven during smelting. I hope that it will help keep the heat on the sides and top from escaping as fast.

[Idaho Sharpshooter]

I would opine, purely from a lazy man's standpoint; that you consider a turkey cooker from Cabela's or Wallyworld. They run on propane, hold well over 100lbs of lead alloy, and allow you to blend in 100lb lots. That consistency is what you need to cast good, boolits and be sure each time that the alloy is the same.

Finding the alloy that works best for you is just the first phase. Repeating the formula each time is the second.

Rich
Sua Sponte

[Jeff82]

This has turned out to be a great discussions for me. I've learned something from each of the responses, and this has caused me to think about what I'm trying to achieve.

I think I'll nix the skillet for safety reasons -- besides it doesn't work. I'm thinking of trying a small commercially designed casting pot for mixing and fluxing alloys into ingots --not sure yet though. I could also just get a larger furnace, or go with both.

One big thing I've taken out of this is that smelting is a different thing from casting and mixing alloy; needs more heat and larger volumes to be efficient. Hence, different equipment. I think I may need to put the smelting idea off for now --future next step.

This has really helped. Thanks!

[David2011]

Jeff,

Some great arguements have been made in other threads lately for the economy of buying ready-to-cast ingots. You might be better off with your current equipment purchasing your alloy from one of the sponsoring vendors to eliminate the smelting aspect of casting.

David

[Jeff82]

Hi David,
I think I agree with your observation. My initial reason for wanting a larger setup was to be able to melt down larger or odd sized ingots from scrap solder, pewter, linotype, etc... Rather than spending more money for pure tin and lead/antimony bars, and then having to cut them up into sizes that are appropriate for my little four pound pot.

Smelting, reading the comments above, seems more like a heavy user's game. I don't think that my modest need for 60 lbs of lead alloy per year justifies the investment the additional equipment, etc. And, since I don't have a reliable supply of free wheel weights or plumber's lead, it's propably not practical anyway.

So, I guess where I'm at now is trying to decide whether to get a small 10lb casting pot, and maybe eventually getting an additional heat source, like a small camp stove for blending alloy and making ingots. Or, just getting a 20-lb casting furnace.

Any thoughts?

[shadowcaster]

Smelting, reading the comments above, seems more like a heavy user's game. I don't think that my modest need for 60 lbs of lead alloy per year justifies the investment the additional equipment, etc. And, since I don't have a reliable supply of free wheel weights or plumber's lead, it's propably not practical anyway.

So, I guess where I'm at now is trying to decide whether to get a small 10lb casting pot, and maybe eventually getting an additional heat source, like a small camp stove for blending alloy and making ingots. Or, just getting a 20-lb casting furnace.

Jeff,
If you are like the rest of us, your needs to the addiction will grow. :) IMO the Lee pro4 20 pound casting pot is a worth while investment, as long as you have clean lead. I have had very good luck with mine in the casting department. You can also use the ladle method as well as the bottom pour feature.

As for smelting.. if you reach that point, a turkey fryer is hard to beat. Plenty of BTU's for the big stuff and then turn it down for the small stuff. Mine cost me about $50 brand new.

I tend to be a bit of a scrounge, therefore don't have a ton of money invested in my equipment, but at the same time it works well and suits my needs.

Maybe some pictures of some of the guys casting/smelting setups would be helpful in your decisions. I would be happy to post some.

Shad

[OuchHot!]

When I started out, I cast using one of the lyman cast iron pots off an electric hotplate. Even with its relatively small surface area, I had to wrap some glass mat around it to cut the heat loss from radiation. That worked with 1 and 2 cavity molds. When I smelted, I used a bigger pot welded up from well casing and a gasoline coleman. That combo worked fine, but I just barely had enough heat. Just barely can be frustrating on cold days!

[David2011]

Hi Jeff,

Just my opinion but a 4 pound pot will work you to death.

Boolits per pound- not sure if you're casting for pistol or rifle.
158 gr- 44
230 gr- 30
300 gr- 23

You'll only be able to dip part of the melt out in sufficient quantity to cast useable boolits. The bottom 3/4" or so is going to be hard to recover without adding more metal. Expect the temperature to vary significantly as you reduce the lead level in the pot. It will freeze and take a while to get back to casting temperature when you add more metal.

Goodsteel, a very experienced participant, recently posting something that my be of interest to you. There's a lot of worthwhile follow-up in the thread as well. Let us know what you think after reading this, please. http://www.castboolits.gunloads.com/showthread.php?t=161647

David

[Jeff82]

Goodsteel's comments are enlightening. I guess I'm thinking of going with a 20-lb Lee pot.

I prefer to ladle cast. I use a hotplate to maintain the heat of my 6-cavity mold, and then ladle cast with the mold resting on the hotplate. This set-up has really improved my casting. It also allows me to cast at whatever pace I like, and to do so without any neck or shoulder fatique.

Lee makes two different 20lb pots, one that's bottom pour and one that isn't. Given the many complaints about the pot leaking and occationally emptying all of its contents, I'm wondering if I might be better off going with one that doesn't have this capability. I could see using the bottom pour spout for ingot casting though.

[runfiverun]

i'd get the bottom pour to mix alloy and pour ingots from.
you then could make more alloy in it and run them back through as you cast.
it's not that hard to ladle from the 20 lber but about impossible from thier 10 lb pot.
plus you might find you like to bottom pour,,, i did.

[mold maker]

You'll either grow in your needs, or give it up. (uhlikely)
Either way, get bigger equipment than what you need right now, and it will serve you longer without upgrading. If you decide to get rid of it, the larger capacity will be easier to sell.
The turkey/fish fryer and big cast pot are the standard for smelting. A bottom pour 20 lb furnace is where we most always end up. Getting them both now will save you frustrations and money down the road.
Watch for sale on these items in the next couple months for even bigger savings.

[WILCO]

So, it's a small scale thing. The ability to smelt would be a modest plus.

Hey Jeff,

Just a thought here. I'm a small scale outfit too and my smelting set-up consists of a hotplate, cast iron skillet and a steel plate lid to keep the heat in. Handles all my smelting chores as long as I'm not in a hurry or trying to produce large batches of alloy. Good luck with your endeavors and keep us posted.

[D Crockett]

Jeff you have a pm that might help you with your problem D Crockett