View Full Version : Weight of Crown - 80# Staedlemelter

Dave Hilty
01-05-2012, 05:18 PM
Anyone have a close approximation of the 80# Moly furnace crown from Steve/Brent. I'm pulling the crucible (finally) and I don't want to overbuild the rigging/chain fall gizmo to do the job. I'm in tight overhead quarters so it's important to stay minimal on structure.


Steve Stadelman
01-05-2012, 05:27 PM
Less than 100 lb. I could easily lift those.

Pete VanderLaan
01-05-2012, 06:15 PM
When you do lift it, I advise distributing the load with some wood planking inside the furnace that the chain or whatever passes through.

Dave Hilty
01-05-2012, 07:08 PM
Thanks to both of you. Wouldn't have thought only 100# to look at it. And I was going to use nylon webbed strapping to pass through the element openings but spreading the load across a plank or even half inch plywood would certainly be a good measure.

Pulled the elements this afternoon without any breakage. Put them on a stand I built to support them while they're out of the furnace (Thanks Rollin).
Surprised to see so little glass attack at the passthrough openings or around the door/front casting. Pete's suggestion to vent for the first 20 minutes of each charge pays off. The bottom 2-2.5" of frax over the crown is crystalizing from heat but almost no attack around the passage brick.

Pete VanderLaan
01-06-2012, 06:38 AM
The planks really help. I actually hate to hear when people are replacing their crowns after only a year. They need support. I think I could well have broken mine front loading the pot. I only lifted the crown 1/2 inch but I supported it. Now I have a spare crown down in the tractor shed.

I am amazed at how much crap comes out that vent hole I put in the front door. It is piling up on the steelwork.

Rollin Karg
01-06-2012, 02:38 PM
I am amazed at how much crap comes out that vent hole I put in the front door. It is piling up on the steelwork.
Yessem, one more regular mainteinence item. Keep the vent clean.

Dave Hilty
01-06-2012, 04:34 PM
The part I hate is having to come back 30 minutes later to seal the door after cracking it with a shim for venting after every charge. Dont want to lose energy from the venting when its not necessary.

Pete do you just leave the vent open during the charging cycles and only close it when you come in the next day? I need an automatic door closer gizmo so I'm not running down to the studio from the house twice for every charge. Wouldn't be so bad if I weren't too old to remember to set my cell alarm to remind me to close the door etc. etc.

Pete VanderLaan
01-06-2012, 06:30 PM
I just leave it open while the melt is going on. It's pretty small, about 3/4 inch across. It angles up at the top of the doghouse door going up at 45 degrees to the top of the door on the outside. I think leaving the door cracked would not work well at all. maybe if you lay a piece of fiber between the door and the rest of the front face, leaving a little space at the top right, if that makes sense.