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New Electric Furnace

Posted: Sat Jun 09, 2012 7:10 pm
by Jammer
I built one electric furnace a few years ago and it promptly fell apart, I'm a glutton for punishment so I made another.
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Using a different type of brick this time, I believe it's an ariated type like the Z-brick. I heated some in the oven (wife went shopping ). They seem to hold up a lot better than the other type.
I built it much like the first one.


It's 240v and got up to 800F in about 6 minutes. I shut it off to let the coils relax, it doesn't look like they shrunk very much. We'll see after a few times at full temp.

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Re: New Electric Furnace

Posted: Wed Jun 13, 2012 2:49 am
by mite5255
That looks great Jammer, what's the maximum temp would you expect to get

Mike

Re: New Electric Furnace

Posted: Wed Jun 13, 2012 6:57 am
by Jammer
I know the first one got close to 2000F, these brick seem more insulating. Going to give it a test run today. :)

Re: New Electric Furnace

Posted: Wed Jun 13, 2012 11:40 am
by mite5255
2000 deg's, that's ok. How is it cost wise to run

Mike

Re: New Electric Furnace

Posted: Wed Jun 13, 2012 2:52 pm
by Jammer
3.6 Kw/ hour, I think that's about 32 cents/hour.
I didn't get to run it today, I decided to pour Beeswax all over my garage. :x What a mess. :cry:

Re: New Electric Furnace

Posted: Wed Jun 13, 2012 5:00 pm
by mite5255
Maybe you should have got the floor polisher out :P .How much wax did you spill

Re: New Electric Furnace

Posted: Thu Jun 14, 2012 9:02 am
by Jammer
It turned out not too bad, about 1/2 pound and it cooled and popped loose pretty easily. Good thing the floor was dirty. I don't think it will come out of my pants as good.

I just started the furnace cold with a crucible of Aluminum at 1 Kilo. We'll see how long it takes to melt.

Re: New Electric Furnace

Posted: Fri Jun 15, 2012 7:40 am
by Jammer
I placed 1.06 K of Al in a clay crucible and put it in the furnace. Everything started at room temp. After 20 minutes the internal temp was at 1400 F and the metal had started to melt. at 30 minutes the metal was almost all melted and the tepm was at 1500 F. At 35 minutes the metal was ready to pour, my pyrometer said the metal temp was 1300 F, I shut the furnace down. I had to answer the phone and came back in a couple minutes, the metal temp was 1350 F and furnace temp was 1600 F. I poured 2 ingots that weighed 1.01 K and had about 45 grams of dross. after being closed up for an hour the internal temp was still at 1000 F. Bricks look fine, no problems.

Re: New Electric Furnace

Posted: Fri Jun 15, 2012 3:36 pm
by Rasper
Do you think it could melt bronze? . . . . . Don't answer this question. I don't need another project. I spend as much time making tools as I do using them.

Good work Jerry.

Richard

Re: New Electric Furnace

Posted: Sat Jun 16, 2012 2:29 am
by latzanimal
Rasper wrote:Do you think it could melt bronze? . . . . .
If so, how much bronze? :D