Hello all, I am in the process of building my very first home foundry after doing much research and one thing I am not certain on is what is the function of putting a brick on the foundry floor to raise the crucible? I believe its called a plinth. My guess is its just a boundry to prevent the floor from sync'ing any heat from the crucible but I am not sure. What would be the effect of just putting the crucible on the floor of the foundry?
Yes, a plinth gets the crucible up so the bottom of the crucible will get hotter. Sitting on the floor the bottom can't get as hot. A secondary benefit is it allows a sacrificial piece so the floor is not damaged if the crucible should stick to the plinth. I use two stacked plinths in mine because I like to have the crucible well off the floor and the flame starting below the crucible. Welcome to The Home Foundry! You may get some varying suggestions but that just helps you learn more. Not everyone does things the same way, but various methods can be successful (not everyone drives a Chevy).
Good explanation Andy. Ryan, make yourself a few different height plinths. This will allow you to set the crucible height to prevent direct flame impingement. Nothing will shorten the life of a crucible faster than a flame hitting it.
I agree, the flame temp will be from 500 to as much as 1500F hotter then the crucible or the furnace depending on what metal is being melted, The flame is also normally a slightly reducing(short of oxygen) flame, The more oxidizing the flame is the cooler it is because of heating the extra air not needed for combustion, the extra air also reduces the fuel efficiency as it reduces the heat transfer rate. Art B
Sage, isn't that a shade of green? Oh, I get it, I know I'm green at this so I must give green advice.
