Electric furnace

[kadora]

Hello friends
I would like to start to cast my own engine parts but i am bigginer
and i need a lot of help .
First i need an furnace . In my city is banned back yard open fire
so i have decided to buy electric furnace.
Please have a look on this ebay address if is worth to buy this furnace ?
http://www.ebay.co.uk/itm/330761134776?ssPageName=STRK:MEWAX:IT&_trksid=p3984.m1423.l2649
I want to cast only small engine parts but i am not sure if this mini furnace
can serve me or it is absolutely useles for engine parts casting.
Thanks for your advice.
Kadora

 

[kadora]

I forgot to say i want to melt aluminium
take my apology.

 

[aarggh]

NOOOOOO!

Sorry, I bought one and can say it's definitely not suitable for anything that approaches any real use for casting, smelting, or high temperature. The heating elements are quite thin and are not designed for many cycles. And at higher temperatures the wire actually breaks due to corrosion with the heating/cooling cycles. Doing brass with mine just kills it, and even for aluminium I have to get it to at least 800-900 celcius to melt due to the heat losses. Mine is now sulking in the garage after the second coil disintegrated, I will get it fixed as it's good for occasional small stuff, but I don't know if doing even just one melt each month, if the element would last in between long enough to get good usage out of it before it corrodes and breaks. The other problem is the 3kg crucible sounds good, but it very, very quickly becomes too small for most stuff.

For the money, your better off getting an old electric top loading kiln that is designed to routinely go up to 1200 celcius, and that should last quite well.

cheers, Ian

 

[///]

...
In my city is banned back yard open fire
...

A furnace is a contained fire.
Some firebricks or castable refractory, propane burner, go for it.

 

[dnalot]

This is a furnace made from and old gas cylinder. It holds a number 10 crucible. I have been using it for two years now and it still looks like new inside. It will melt aluminum quickly and bronze but slowly. I plan on adding an inch and a half of ceramic insulation this year to improve its performance, and some wheels because its to heavy to lift with my old back. I keep on old crucible in the lower compartment to catch any spills.

The photos are from its first fire. I do my foundry work out in the driveway as you don't want to spill any metal on the concrete as it will cause a steam explosion.

Aluminum is the most economical metal to recycle, needing only 1 percent of the energy needed to produce it in the first place. I prefer salvaged outboard motor castings as they flow quiet nicely. Extruded salvage is not very good but you can mix a little in.

Mark T

 

[jwcnc1911]

dnalot... That is fantastic! I'm very curios about this... I've been considering a dive into home foundry for a few years now. Would you provide details on the burner? How you "coated" the inside of the old cylinder with what ever that is (it looks like Quik-crete)? Specific curiosity because my time is already so limited... how long does it take to melt "1 batch" of aluminum? brass/bronze? Have you ever done iron or steel?

Is that burner ceramic? Do you use forced air in any way?

So many questions...

 

[dnalot]

That is fantastic! I'm very curios about this... I've been considering a dive into home foundry for a few years now. Would you provide details on the burner? How you "coated" the inside of the old cylinder with what ever that is (it looks like Quik-crete)? Specific curiosity because my time is already so limited... how long does it take to melt "1 batch" of aluminum? brass/bronze? Have you ever done iron or steel?

Wow, it would take a book to answer all of that. Lucky for you there is (Gas Burners for forges, furnaces by Michael Porter) Step by step instructions.

The book gives details for several size burners, a number of furnace and a forge. The liner is 3000 degree refractory that I bought from a pottery supply house. No blower is needed ( yet it sounds like a jet )and it can melt 10 pounds of aluminum from a cold start in about 45 min. and the second load takes about 20 min. Double that and then some for bronze. Note that there are different types of bronze with a wide range of melting temps. Cast iron is beyond my reach.

Mark T

 

[aonemarine]

Heres my propane furnace melting iron...[ame]http://www.youtube.com/watch?v=CbLBiCdgRi4&feature=share&list=UUSrlSdQ3dLlHlahmmmYbb2A[/ame]

 

[jwcnc1911]

Wow! You make that look so easy.

 

[enfieldbullet]

i think the OP wants something low profile.

an electric furnace would do well there. perhaps an induction furnace.

 

[dnalot]

That is great. Does your furnace have a blower?

Mark T

 

[cfellows]

I've built several electric furnaces that work fine for melting aluminum. You can buy heating elements which are nichrome or kanthal wire coiled into a long spring shape. For insulation, you can use insulating fire bricks which are about about 11.5 x 23 x 6.5 cm and are very soft. They can be cut with common hand tools like a hacksaw and file. You can also use Kaowool which is a thick fabric type of insulation. For a container, you can use large popcorn cans or spaghetti cooker.

Chuck

 

[aonemarine]

That is great. Does your furnace have a blower?

Mark T

When I cast Iron I use a blower (hair dryer) but for anything else I dont need it.

 

[Mike N]

I bought one of these:

http://www.foundry101.com/Furnaces.htm

http://www.foundry101.com/search.htm

Works Great for Aluminum & Brass!

 

[Jon]

If you want to build an electric furnace, check out Dan's Workshop Blog. Specifically, the page about his electric furnace. I think I first saw it on the Backyard Metalcasting forum. He sells plans for it on his site for $3.95US. I thought enough of it that I actually bought the plans. I haven't gotten around to actually building it yet though.

For the heating elements, see Budget Casting Supply. They pretty much have everything you will need. If you really want to get serious about your furnace, they even have programmable furnace control boxes. With that, you can even use your furnace as a heat treat oven.

I hope that helps.

Jon

 

[kadora]

Thank you guys .
Kadora

 

[gocy]

All the comments and links are very helpfull.
thanks

 

[kadora]

why are electric kilns so expensive?
Good quality SMALL hobby kiln costs 1500 EUR here compare to
100 kg Optimum bf 20 milling machine it cost the same price - strange

I have found vendor of electric heating chamber with kanthal wire 2,6kW
1200 C for 280 EUR.
Probably i will build my own kiln but i am not brave enough to start.
Best wishes Kadora

 

[Wizard69]

why are electric kilns so expensive?
Good quality SMALL hobby kiln costs 1500 EUR here compare to
100 kg Optimum bf 20 milling machine it cost the same price - strange

I have found vendor of electric heating chamber with kanthal wire 2,6kW
1200 C for 280 EUR.
Probably i will build my own kiln but i am not brave enough to start.
Best wishes Kadora

I was going to say it is the European disease then I realized that you are talking about kilns which are exactly cheap on this side of the pond. Around here I would look for used or business close outs / going out of business auctions.

As to building your own, you will never get anywhere if you don't try. This is a serious AC power project though so if you don't have experience there, I'd highly recommend getting help with the build. Oh by the way controls can be a big part of your cost depending upon how compliant you won't to be and how fancy with that control you are. I must reiterate though get help if you aren't familiar with high power AC systems, the wiring can be lethal.

 

[mecanotrain]

Hello guys,

Kadora, I built an electric furnace for brazing. I also used to melt aluminum.


Here the construction of the oven; the total cost is 200€ max.
https://picasaweb.google.com/109200417126637456771/FOUR1100C#

Regards