Brass gate valve on lead melter

[Mollyboy]

so what is the best valve for a home made smelting pot?

Plain steel would be the least costly. Stainless steel would give the best life but costly. An old cast iron gas valve would last a reasonable length of time.

[BattleRife]

So explain with you data books why my 4 Lee casting pots made of steel and are 20+ years old, have not been totally dissolved by my molten lead years ago?

banger

Because steel has a very slow dissolution rate in molten lead, particularly at the low temperatures used for bullet casting. It would probably take 100,000 hours to dissolve a Lee pot. Even a regular caster isn't going to expose his pot to much more than a 100 or so hours a year.

[pjh421]

Your instance here will have to take some serious thinking and planning.

Sometimes the simplest solutions ( example: the valve on a Lee bottom pour!) are the best.


bangerjim

Thanks Jim! I just ordered that Rowell #6 ladle I've been putting off for 10 or 15 years.

[nun2kute]

substitute that valve for a pivot, add a pour spout to front/back and a long handle for control. pour it out like the 1/4 yard cement mixers. any way you go, keep us posted. preferably w/pic's

[bangerjim]

Thanks Jim! I just ordered that Rowell #6 ladle I've been putting off for 10 or 15 years.

Good choice for a dipper! Some try to use simple spoons or regular pouring ladles. The side/bottom pour design of the Rowell is the best. I have a smaller one and use it for a few "fussy' molds that do not like my 4-20 Lee bottom pour pots.. Not cheap but very useful and works great! A tool you will have for many years.
Enjoy your new toy!

banger

[pjh421]

It arrived yesterday and holds about 18 pounds. I hope to use it this weekend.

[10sandxs]

I can't speak for Mollyboy, but my go-to resource is High Temperature Corrosion of Engineering Alloys, by George Lai. Your melting point information is useless: as pointed out by Mollyboy and affirmed by the book, the wastage mechanism is dissolution, just like salt dissolves in your soup (at temperatures way below the melting point of salt).

I don't have data for brass or aluminum, it's all for ferrous alloys, but that data shows corrosion of those materials by dissolution in lead can be significant. Cast iron is apparently particularly susceptible, and the corrosion test sample was completely destroyed in 400 hours of immersion.





You're welcome.

Temperature and reaction rates are not linear, they are often exponential depending on the reactants. The rule of thumb is they double for every 10 degree Celsius increase in temperature so from 300C to 1000 C is a lot of doubles...

Take home message... corrosion conditions at 1000 degrees don't mean anything at 300 degree. Your cast iron or steel pot won't disolve in a few lifetimes of lead smelting... just ask the old plumbers who poured lead joints... with cast iron pots... that were used almost daily...

Sent from my SM-G973U using Tapatalk

[10sandxs]

Sorry it took so long for me to post this, but this is a smelter I made haphazardly about a decade ago. The valve consists of a simple Threaded rod With a point ground on one end A nut is welded to the top of the pot and a guide nut with the threads removed welded to the bottom. A hole is drilled at the bottom of the pot for the point to go in And a vise grip is used to open and close the Valve by turning the Rod. Simple but effective. The plan was to make it more sophisticated someday , maybe when I retire.

Sent from my SM-G973U using Tapatalk

[bangerjim]

Simple is the best! The idea follows the design of the Lee 4-20 except gravity is eliminated from the shut-off question.

Only a turn is needed for good flow? And with the leverage on top, you can crank as hard as you need to get good shut-off sealing.

Good ideas to ponder for those that want to built a large volume melter!

banger

[10sandxs]

I drilled a 1/8" hole and put a long taper on the pin. Lead flows at .25 turns, but full flow needs 1.5 or 2 turns. But yes, it never leaks...

Sent from my SM-G973U using Tapatalk