Looking for ideas for a bottom pour spout/valve

[JeepsAndGuns]

Working on my lead melting pot for larger batches, I have acquired a old portable air tank that had a broke hose/vale assembly on it. I cut it open with a cutoff wheel and angle grinder. It is nice and clean on the inside.
This will make a nice melting pot for large batches. I plan on getting some kaowool and some flashing for the outside of the tank to help keep the heat from escaping and making the lead solidify on the outer edges.
I am also working to reinforce my stand and add some braces to hold the taller pot and keep it from turning over.

I got wondering how I could make some type of a bottom pour spout/valve to come out of the bottom of it off to one side, so I could easily pour the lead into the ingot mold from the spout/valve.
A actual spout is not the hard part, just some metal tubing I can weld to it. My issue is figuring out some type of a valve to shot off the flow when needed.
I figure this would be much quicker and easier than using a ladle to hand pour 150 pounds of lead into ingots.

Anyone have any suggestions/ideas?

[Retumbo]

Oops,

[justindad]

Ball-in-cone poppet valve? Check McMaster-Carr for steel balls that are not too hard to drill & tap, then put that on the end of a spring loaded rod.
*
The geometry of the ball and the cone must be very good, or you’ll get leaks.

[414gates]

http://castboolits.gunloads.com/showthread.php?146065-New-bottom-pour-smelting-pot!

[Nueces]

I have thought about this and would choose the valve I believe was used on Satan's Little Smelter. It appeared to be a threaded rod, T handle at top, and with a cone point at bottom that interfaced with a hole. I don't think a formed conical valve seat to be necessary. A plain drilled hole would have a good seat formed by screwing the valve stem in; would seal better with use. Crank it down to close, crack it open to meter the flow, and easy to clean and maintain.

[fredj338]

My buddy is a welder & made me a smelting pot with bp spout. A drilled hole & tapered bolt to close it off. Bolt has a T welded to the top & its threaded thru a metal plate welded on top. Works great.

[BattleRife]

Mine is just a threaded coupling welded to the outside shell, centered over a chamfered hole. I had a friend take a bolt that fits the coupling and turn the threads off the end, and taper the end to a cone.

https://i.postimg.cc/MThVvdGk/Tapping.jpg

I went back and insulated it better since this photo was taken, as it was prone to freezing up.

[Winger Ed.]

I'd put a drain pipe part way up the side of the pot so you could tip it and pour the Lead into molds.

With my luck, the valve would freeze and I couldn't stop the flow if I needed to.

[megasupermagnum]

I'd put a drain pipe part way up the side of the pot so you could tip it and pour the Lead into molds.

With my luck, the valve would freeze and I couldn't stop the flow if I needed to.

I'll get a picture of mine later. Freezing is definitely an issue, and you do not want to just slap some gate valve on the outside and hope. You will want a small propane torch to aid you anyway, but the spill before you could get it closed would be bad. I'm not sure how I feel about BattleRife's setup. It must work for him, but I'm not sure about it. I went with a tapered seat, just like a bottom pour casting pot. There are a number of different versions you can find, but most of them use gravity to close. I decided to go with threaded. Threaded is a much more secure way, you know with certainty that it will not fail. The only drawback I have found is that if you leave it closed tight, then heat the pot up, the expansion can cause it to really bind to where you then can't open it, but I simply take the bracket loose. With pictures it will make more sense.

[BK7saum]

I built mine out of 1/4 plate and 3/8 wall pipe. I welded a street elbow into the bottom near one side, then took a 1/2" cold rolled rod and ground a taper on the end with an angle grinder. I welded a spacer and nut on the inside top of the pot for a guide/locator above the street elbow. I then put some valve grinding compound on the taper and spun the rod in the street elbow for a while to create a seat. Then cleaned it all up, added a threaded nipple and a second street elbow tuned downward for a spot. My pot stand has a shelf about 3" below the spout.

Works quite well and used the common tools at hand. You have to twist and raise the rod to open but it isn't a problem to close.

Every now and then you need to heat the spout to allow lead to flow. If you are pouring at a good pace, it stays hot. A little aluminum foil over the spout does help hold the heat, though. Opening the valve fast is best to get/keep the spout hot. I usually pour 8lb ingots into C-channel molds, though.