Electric Furnace Info

[Glenn Randle]

I'm getting tired of having greasy hands and spending my time tending the fire. I'm not giving the waste oil up yet, but figure I should begin thinking about my options.

I'm interested in learning about building an electric furnace for melting batch. I'll be using a 300 lb pot and a couple of smaller color pots. I have a 400 amp single phase service. I'm not a beginner and I enjoy constructing studio equipment.

I know there has been much discussion in various threads here and I could search through them. In fact that seems to be the first response I've seen to many posts asking about the details, "Go search through the archives". The other common response is "Just buy one from Steve, better get on the list soon." Steve's a great guy, but why would I want to pay him for the pleasure of building MY furnace. That's a lot of beer and fun I'd be missing out on! Steve know's what I'm talking about, he likes good beer too. And welding, wiring, casting, all of it (except cutting & stuffing Frax!).

If someone would just point me to a particularly good thread or better yet, just post a simple list of the necessary components for putting together a Moly and/or SiC furnace. Also any reccomendations of suppliers for the parts would be great too.


Thanks,
Glenn

[Richard Huntrods]

I agree with what others have said in the past, esp. about buying from Steve.

However, if you are determined to build, there is one resource to consider if you go SiC:

http://mayneislandglass.com/170lbinvestedsicfurnace.htm

Mark Lauckner now has a video on building a 170lb SiC furnace. His videos are very good, and his equipment is very good.

That said, you WILL be told that SiC is a very bad option for a glass furnace compared to Moly. As I have no experience in either technology, I leave that debate to others who do.

I am merely posting Mark's information as an alternative that may be considered.

Cheers,

-Richard

[Dave Bross]

The basic moly building info is saved in the antiques and classics section here. It's mainly the electrical info.

[Glenn Randle]

Thanks,
That's what I was looking for.


:)

[Glenn Randle]

Mark Laukner's SiC furnace looks like a nice clean simple design.

Are there any moly furnace photos around? Can moly elements be suspended horizontally from opposite ends, like he does with the SiC ones? From my limited reading I'd thought they are usually hung vertically, is that correct?

Has anyone here constructed a 170 lb (or larger) furnace per Mark's design? Any negative and/or positive comments about it. (I personally don't care for vertical doors, but that's simple to change).

.....I'm heading back over to the "antiques & classics" to study a bit more....


Thanks,

[Rob Dworkin]

http://www.duralite.com i like these guys for parts and design.

mark is a good resource too. i haven't seen his SiC video but the wire furnace ones are good.

[James Ennis]

hey glenn, I have helped buld and repair
more than a few SiC furnaces, and know of 4 in seattle that have around 300 lb to 350 lb free standing pots, and work verry
well, most run the elements along the sides or accross the back, I have not worked on one with the elements
over the top,but like charles f.
says you just need to be carefull not to
get glass on the elements, and dont let the new guy charge!

[Rob White]

Moly Elements have to hang vertically in a U shape, usually from the crown. They get soft at temperature and can stretch or sag a little, so hanging them horizontal won't work.

Rob White

[Pete VanderLaan]

Moly elements are made that come into the furnace from the side and then hang down. Not common and they are painfully fragile.

[Brent Hickenbotham]

there are a plethera of different moly elements to be hung in various ways, but when you actually get into designing a glass melting furnace to accomidate them its gets kinda scary. :eek:

[Pete VanderLaan]

kinda scary? I think totally scary. The worst thing about elements is shipping them and the breakage rate.. If you buy an off style, immediate replacement can take some serious time and the only in country fast replacements will be sentro tech or Kanthal and you will really pay. I'd stick to the common imports from steve.