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View Full Version : Getting ready to fire up the BIG pot.



2ridgebacks
03-24-2014, 10:37 PM
We have received our pot from the shop. I am a bit embarassed/disgruntled that I didn't build it, but I don't have a shop to work in outside of my job and the other guys are getting a bit impatient.
We commisioned a 14" O.D.x 1/4" wall by 16" high pot. The bottom is 1/2". I drew up a bottom pour using a threaded t handle with a plug and matching, 1/2" seat. The seat sits on a block that is a 1/2 thick to get it off of the bottom. That feeds a 1/2" nipple to pour from. The pot probably weighs 40-50lbs. I'll post pics later when we start smelting, which should be this weekend. A cubic foot of lead is a tad over 700 lbs. This pot should be upwards of 500lbs, wet.
Why? Why not? There is a good reason. We are sitting on close to 4k in isotope lead and another 3-4000 in very clean range scrap. Even with this, we are going to be busy for a while.
The final two pieces of the puzzle are a burner and ingot molds. I have molds, but not for this volume. We have a 250k brewing burner and stand on order and should be here soon. It was a bit of a W.A.G. on size. I actually started considering a 500k untill I found out the other had been ordered. And, I will be reinforcing the enclosed stand or building a new structure around it. The ingot molds, I am fabricating from 8" channel at 2 1/2" long. They will be single molds and not ganged together. We are thinking around 20 will suffice and are entertaining the idea of putting them on a board that rolls on pipes under the spout for filling.
Would anyone like to speculate on the suitability of the burner for heating that large of a pot of lead?

Can anyone tell me anything about how much angle is needed on the end plates for the molds to get them to drop easily? Due to the volume being made, the plan is to tack at the bottom and lay the top out before welding into position. Machining or cutting on an angle wasn't an option. I'm hesitant to weld on the inside, but I know I will have to fill the gap if I don't. Gas welding the gap or filling it with brazing rod is looking like an option if I don't weld it. I'm figuring on ingots around 12lbs. Any other input on these molds is welcome.

Ultimately, the process will be as follows:
Iso lead and recovered indoor range scrap (bullseye range 98% of the time) will be smelted to ingots.
Ingots will be cast to 45 a.c.p. swc boolits in a Ballisticast Mark X that is awaiting a recut set of molds as we speak. It is a nice machine and I will post pics and video later.
Said boolits will be sized in in our vintage Star lubrisizer or yet to be received Ballisticast Mark 6.
After a quick trip through a 650 Dillon, the projectiles will be fired downrange at near slingshot velocity (it is bullseye pistol) through the ten ring and into the backstop. At that point, most material will be recovered and we will start all over again.

When we get rolling, I'll put some pics or video up. This should be a 3 or 4 guy operation and there should be more than enough work to keep everyone busy.

Trapperscott
03-25-2014, 07:23 PM
Can anyone tell me anything about how much angle is needed on the end plates for the molds to get them to drop easily?

I just made 5, 5 gang molds and cut the ends of them at 5 degrees on my Bridgeport mill. They work great.

Sgtonory
03-25-2014, 07:30 PM
Would anyone like to speculate on the suitability of the burner for heating that large of a pot of lead?
Yes should work fine.
I use a pot that holds 4 5gallon buckets of range scrap and it takes 90min to melt it down from a colt pot and i get around 300ish LBS out of each smelt. I have seen the video on what i would think is the same burner you got and mine seems to put out less but it works fine. Slowly heating the leads seems to work well as i get less radiant heat and the less dose not oxidize as fast.

Sgtonory
03-25-2014, 07:35 PM
Can anyone tell me anything about how much angle is needed on the end plates for the molds to get them to drop easily? I use a 45 degree angle and everything drops out great. You can try and just angle one side i have use a mold like that and it worked well also.

runfiverun
03-26-2014, 12:21 AM
a 5* angle will do the job, more is better but 5 is enough draft angle.
I welded my gang mold up on the outside if you want a smooth inside, puttying it with jb weld works pretty well.

dikman
03-26-2014, 01:10 AM
As long as you've got a slope on the ends then the angle doesn't really matter - 5/10/15 degrees, whatever. If the end pieces are a good fit, I don't see any need to weld the inside. I whipped up some angle iron molds by cutting the angle iron ends at a slight angle and tack-welded them, on the outside, to a flat bar. No welds on the inside. They work fine.

clodhopper
03-26-2014, 01:14 AM
I made gang ingot molds with what ever angle you get from propping the angle iron up with a 16penny nail (with the head cut off) 1" from the cut with an abrasive saw.
Welded on the outside like runfiveruns but did not bother to putty up the cracks. The cracks are almost 1/16 but have not been a problem. Probably would be if the ingot mold got to hot.

Hammerlane
03-27-2014, 07:57 AM
I have found that the problem moving freshly poured ingot is that every little moment causes the lead to move and cause overflow or the bottoms to be uneven. To solve this problem, Once the angle iron molds are ganged together I ground 3 separate curves on the top connecting the ingots together. So the lead flows from one ingot into the other and is held together by a 3 small tabs. Let them setup enough to dump. This also helps in stacking as you don't need the make a pyramid. Much like over pouring a Lees mold and breaking them apart.

dilly
03-27-2014, 10:37 AM
I couldn't guess how much heat you'll be needing, but I will say it's often less than people think IF they use a proper heat shield. In an operation this big I would definitely recommend one or you may lose a lot of efficiency/profit to fuel costs.

2ridgebacks
03-29-2014, 08:35 AM
We fired it up with the modified burner stand last night. The burner boiled 6.5
Gallons of water in 30 minutes. The temp actually came up fairly quick once that 1/2" bottom got some heat in it. The valve had a very slow drip after heat was added to the cold pot. The best that I can figure, an inch of lead depth should be about 53 lbs. With 12 inches to the spout block, we'll be well over 600lbs to a batch.

imashooter2
03-29-2014, 08:51 AM
If the burner boiled water in 30 minutes, it's going to be over an hour and a half to melt lead. I'd look for more heat. A weed burner from the top maybe...

2ridgebacks
03-29-2014, 09:50 AM
Is that based on experience or lead melting at 3 times the boiling point of water or a WAG? I'm not doubting you, I'm just curious. Future plans call for firebricking around the burner base to most of the way up the pot to hold heat in against the side of the pot. I think a lot of the 30 minutes was heating the pot. There is a lot of mass in the pot. That was the idea though, as the second pot should heat faster than the first. There was some thought given to dropping a burner element or water heater element in the lead to help too.

imashooter2
03-29-2014, 10:00 AM
It is a wag based on some experience. Lead needs to get to 3 times the temperature to melt, plus the heat transfer is not nearly as efficient. There is a lot of air space in lead scrap / WW / isotope cores.

2ridgebacks
03-29-2014, 10:51 AM
I think we're going to fire brick up to about a foot on the pot to help hold the heat. I'll know more next week. I'm finishing ingot molds now, so we could be making a trial run Monday.

2ridgebacks
04-12-2015, 05:43 PM
136710Well, a year later we managed to corner the market on reclaimed lead.

2ridgebacks
04-12-2015, 05:45 PM
136711

2ridgebacks
04-12-2015, 05:47 PM
136712That is the first batch at 14 lbs each. Now at 2000 and counting. Yesterday afternoon And this afternoon with pics to come

2ridgebacks
04-12-2015, 05:50 PM
136714

2ridgebacks
04-12-2015, 07:42 PM
136740Sorry for the sideways pics. 3420 lbs in two afternoons.

carbine
04-14-2015, 03:21 PM
Awesome

62chevy
04-15-2015, 03:58 PM
That will make a hooooolllleee lot of boolits.

bumpo628
04-20-2015, 12:46 PM
Nice setup. I'm a bit jealous of that pile of shiny bricks.
How much does each one weigh?

2ridgebacks
04-21-2015, 06:17 AM
Each one is 14-15lbs. We should be melting again soon.

RogerDat
04-24-2015, 06:20 PM
I believe I just proved drool is bad for keyboards. Oh wait, you now have to move 3420# of lead ingots? I guess I lack the ambition to go with my coveting of your pile-o-lead.

Bigslug
04-26-2015, 01:44 PM
2ridgebacks, can you show us some pics of the hardware you used to make your bottom-pour smelting pot? I seem to be headed in that direction, and could use a little guidance on the spigot construction.

2ridgebacks
04-26-2015, 10:13 PM
I didn't take a picture, and I think mine is the same or similar to another here. I spec'ed a 1/2" bottom to retain heat and avoid warping. Warping is not conducive to sealing. On that bottom is a block that has been welded. The block is bored through with a countersink or seat cut into it. A rod with a taper or needle engages the seat to seal. I asked to have the needle lapped to the seat. The rod is 3/8", the needle is larger, but small enough to go through a 1/2" threaded hole. About 2/3 up the pot is a support welded to the side of the pot. 1/2"x2" on edge I believe.to that, they used round stock bored and threaded for 1/2-13. That reduces back to 3/8". I didn't spec that, but it's what they did. As for the spout itself, it is just a 1/2" nipple welded below the block.it works well, but as was suggested, I wouldn't want to pay the fuel bill without the fire brick. I didn't brick it up, but next Time I'll stack differently to keep the pour pipe hot.

2ridgebacks
04-26-2015, 10:21 PM
I'll add this too. The way we bricked it or for another yet to be determined reason, there was a good bit of heated air kicking back out past the propane hose. Enough that it melted the plastic inside the braided and it slipped out if the swaged fitting. There will be a copper line extending back a bit from the burner. We repaired with a hose clamp and a wad of foil for a heat shield for now, but it was interesting briefly.