Anyone make a two stage melter furnace?

[Drew P]

In the quest for stable melt temps I’m considering adapting a second 4-20 pot on top of my 4-20 pot so that the top pot ore melts the lead, and the lower pot receives little doses of lead that will allow the final pot to stay more stable in temps. I was thinking I could link the rods so that when I’m pouring into the mold the top pot is feeding the lower pot simultaneously. I’m already pre heating ingots but there is still a big dip in temps when I put in a new ingot or cold sprues.

[Winger Ed.]

Should work.

I'd thought about making a pot to heat on a propane cooker that had a drain spout in the side near the bottom.

I was going to use it for wheel weights. As they melted, the Lead would drain out into another lower pot,
and the clips would stay in the top pot to be stirred and raked off.

I just never quite got around to building it.

[country gent]

I have made that set up for myself and a couple others with the older 10 lb pots. I set them up so that you manually emptied the upper into the lower for 2 reasons 1) its easier to do and I think it works better. 2) she spouts arnt really flow rated so if the top pots flow is faster you may overfill the bottom one as you go. If you go with the "auto fill" you will want a guard between the 2 pots for splatters and small splashes that occur. We did this to maintain a supply of molten metal when casting big bullets.Run 1/2 lower pot and dump upper then refill with sprues and ingots. You want to run the to pot hotter than the lower to make up for what is lost in the small stream flowing.
You an do this several ways. You can spot the spout thru the base with a square and use a hole saw to cut a passage in it. On the old pots you can reverse the base 180* and clamp to a stand also. We used the tall pot on the bottom and the standard on the top this cut down on height and distance the lead dropped. Be sure to leave room to flux the lower pot also.

[BrutalAB]

Another reason to do it manually is if the pots drip at different rates.... and so you can clean out the spouts when they get clogged at different times....

[Silvercreek Farmer]

I see no need for a second casting pot unless you just really want it. Just put a pot/pan on some sort of suitable burner, tune the temp, and ladle over as needed.

[NikA]

I went for a different sort of 2-stage pot: added a supplementary heater to mine that is powered by the alarm relay on my PID. Really helps the pot get up to temp when heating from cold and reduces temp variation when adding ingots.

[Drew P]

I see no need for a second casting pot unless you just really want it. Just put a pot/pan on some sort of suitable burner, tune the temp, and ladle over as needed.

That seems more complex than a second casting pot lol.

[Drew P]

I should add that part of my casting had expanded to 1lb dive weights and believe it or not they are much more sensitive to temp variation than bullets and also take a lot more lead obviously. That mold has a window of about 40° that must be kept within.

[Leadmad]

Drew P, interesting you bring this up, I tried it using second pot mounted above casting pot with a small pulley above both and braided cable attached to a floating steel weight in bottom pot and opening handle on top pot only used it a couple times and wasn't practical for fluxing etc and little room for my PID, It simply was just over engineered, so I now use the same 2 pots side by side in a master /slave configuration , cold ingots and sprues in slave and steady head and temp in the master, I transfer melted up to temp lead from slave across with soup ladle when level drops enough in master and works very efficiently with only 2-5 degrees temp drop in master pot if at all, I also have temp gauge in slave pot so only bring across when its up to temp, easily keeps up with 2 x 4 cavity moulds with very little interruption to casting cadence

Cheers

[onelight]

I have not tried it but it would seem even a hot plate or maybe electric skillet something that would preheat lead to 4 or 500 degrees would speed recovery of the working pot when adding to it. Just a thought.

[lightman]

It will work ok. Rather than doing that I just stack some ingots on my hot plate. Before I had a hot plate I stacked them around the rim of my casting pot.

[JimB..]

Why not just work the two pots side by side? When one gets low fill it up and go work from the other until it gets low, fill it up and switch back.

I’ve thought about hanging a long ingot above the pot and having it added automatically as the lead is used, but so far my only idea requires that the pot move up as it gets lighter, and that seems problematic.

[toallmy]

A member hear a few years ago in a post explained the art of stacking ingot on the rim to pre heat them , that has taken care of my needs , I keep my 4/20 full most of the time with this method .
But with your 1 pound weight I can see where a over pot to refill your casting pot would be very useful or the 2 pots with a ladle could test the ability of the pots to keep up .
With your need to pour larger volume possible casting out of a larger smelting pot with a ladle and 50-75 pound of alloy over gas would be more useful .
I'm the one that usually needs to tap out first during a extended casting season not the pots / I drink to much coffee .

[Drew P]

Yeah good point about just using two pots side by side instead, I have just done so much work to my 4-20 to make it perfect and it finally is so I’d hate to do all that again lol. As far as keeping the levels matched up that wouldn’t be a problem, as stated I’d use a type of linkage that allows the top pot to be help open and fill up the lower a bit when needed, or use a ladle, and set the mech so that the top pot deposits slightly less than the bottom uses on each pour. Or something of that nature, basically make it so that you can pour either pot independent of the other, but link them to extend the time between messing with them. The points about fluxing and splashes are well heard.
As far as warming ingots goes my issue with that has been that while it’s helpful, a lot of the energy needed to melt lead is going to the phase change between solid to liquid. So that’s still brings the main pot down a lot even if the ingot is close to melting. And then there’s that, I’ve melted a few on the plate by accident and it’s not a lot of fun lol. And if I set the plate temp so that an I got will never liquefy, then it takes a long time to get them up to the set temp.

[onelight]

how about one of these only 4lb but made to pick up and pour from. A hot pot
https://www.amazon.com/Do-It-Molds-1.../dp/B002QG3H9M

[kevin c]

I put my 4-20 on top of my ProMelt. I shortened up the hardware and used a hole saw to open the base plate. It's clamped just using a couple mending plates, nuts, washers and thumbscrews. Both PID controlled.

I figure the number of boolits and sprues being poured that approximates one ingot of alloy and when I drop that many I refill the lower and a new ingot goes into the upper pot. I keep the next couple ingots to be used on the rim of the Lee anyway.

The lower pot stays at temp continuously because the ingots, sprues and rejects only go in the top pot. The head pressure and therefore the stream of lead filling the mold hardly changes. My cadence is only altered for a few seconds to feed the lower pot and then the upper.

I feel the double pot set up allows good consistency and high volume production with a gang mold at a less than half what a magma pot would cost me (though if I were willing to spend the money...;^]).

[DonH]

When volume casting I used to pour from a bottom pour pot while keeping a supply of molten lead in a separate dipper pot. When needed I used a ladle to move metal to top off the "pour" pot. Worked fine for me.

[DonH]

When volume casting I used to pour from a bottom pour pot while keeping a supply of molten lead in a separate dipper pot. When needed I used a ladle to move metal to top off the "pour" pot. Worked fine for me.

[Ausglock]

My twin Lee pots

[Springfield]

Of course the easiest way to keep up with volume casting is to buy a Magma pot. Not only is it larger at 40 lbs but the heater band is 1500 watts.