Home foundry question

[No skills]

Hi all,

I might knock up a mini (charcoal) foundry when I get some spare time and have a mess around casting some aluminium. I have a lot of things I need hanging around but I'm unsure on the materials needed for the foundry lining.
Theres a few videos on youtube using various mixes and various materials, has anybody here actually made one for themselves and what have you used?

Cheers.

 

[woodfarmer]

Actually this is something that very much interestd me. I have a need to make some bronze castings never done it before or seen it done.

 

[woodpig]

Here's a start:

http://www.backyardmetalcasting.com/refractories.html

I've used the cat litter, perlite and portland cement mix for a small forge. Bit messy to mix but it worked well enough and cheap of course.

 

[Water-Mark]

I've been looking into this recently to cast some of the brass scrap i have and the biggest problem has been the lining.
Foundry cement seems to be the done thing especially if it's gas fuelled, but finding a supplier willing to do small orders is proving difficult.

Good luck with it and i think a wip thread would be good.

 

[Jamesc]

These guys are always advertising in the Model Engineers Workshop magazine http://www.johnwinter.co.uk/. I too have been interested in casting and phoned them a few years ago, they were very helpful but I didn't get any further so can't say what they are like to deal with.

Have you found the gingery books on casting? I have several and they are well written down to earth guides. The first one is all about building a charcoal fired foundry. The books are on Amazon for a few quid http://www.amazon.co.uk/Charcoal-Fo...e=UTF8&qid=1426240199&sr=1-2&keywords=gingery

It could be worth searching for Gingery Casting as he produces a whole series of books and there is quite an active community around them.

Regards

James

 

[nanscombe]

There was another thread recently which might be worth a read.

Charcoal barbecue for heating metal.

 

[Dee J]

Made a little charcoal furnace years ago. 5 gallon drum lined with cat litter/portland mix. Blown with a gas boiler exhaust fan. Used the bottom half of a small co2 fire extinguisher as a crucible. Aluminium worked ok using old castings and extrusions as feed stock (don't bother with cans, all you get is dross). Did once stretch to melting and casting brass - old pipe fittings and taps, made a house number plaque that I was very pleased with (cast in a clay mold). BUT the fumes were horrible and the whole project was horribly dangerous. The steel make-do crucible was very marginal - that hot and it's loosing strength and burning through. SO FUMES, HEAT, SPALLING CONCRETE, EXPLODING molten metal if there's any water about. So research, read, learn, understand, wear appropriate PPE and have emergency procedures in place.

 

[Wildman]

I have a small gas furnace, never fired it up yet but intend to do so very shortly. The previous owner melted cast iron in it so will see how it goes. I have a stack of brass, copper, lead, and aluminium to play with, I made crucible handling tools a year or two ago, have the casting sand and made the casting boxes, just need to make some patterns now, maybe one day I'll get around to making my traction engine.

 

[No skills]

Well then thanks for all the replys and information everybody

My foundry will certainly be charcoal powered, its only a fun project and I don't want to spend out much on it (gas bottles etc). Hopefully I can do aluminium and maybe some brass (copper?) with it.

Woodpig and Dee J, you say you have used the cat litter mix - did you use the litter straight from the packet or did you crush it up or anything first?

I hear the H&S recommendations, I have plenty of experience with sharp/hot/poison/flammable/noise etc etc so I will be carefull.

One consideration is the fire extinguisher crucible, if there not really up to the job I do have a smallish co2 cylinder somewhere which is quite well made - if needed I'll butcher that as an upgrade to the fire extinguisher.

Materials I have so far...

20l tin
Sand
Cement (probably, need to make sure its still ok)
Small piece of scaffold tube
Hand dryer blower

More to find...

8)

 

[woodpig]

When I made mine I just soaked the Cat litter (Bentonite) in water until it became workable. It's hard work mixing it but not too bad provided you don't intend to make a lot of if.

 

[No skills]

Thanks.

 

[Keith 66]

I work in a school as a workshop technician, now most schools used to have small scale metal casting facilities in D&T normally in aluminium. Today many wont do it due to being risk averse! However its still on the syllabus & often acomplished using low temperature casting systems.
I remember at the college where i worked about 7 years ago we did a casting project. a student did an A level major project casting a custom rocker box cover for a VW engine. It was the first & last time the furnace had been used in 10 years. It went perfectly & the lads loved it, the flame roaring out of the furnace, red hot crucible, molten metal ,sweating technicians suited & booted to the max, proper real mans work! 6 months later higher authority scrapped it as it was deemed too dangerous. Today we have been doing sand casting with pewter, nearly as impressive but a bit safer!
We use Petrobond oil sand, it is good for aluminium at least. This company do a good range of equipment & materials,http://www.anvils.co.uk/ ,
The primary rule is moulds must be bone dry, water & molten metal dont mix.
Also consider that all tools must be preheated before picking up red hot crucibles, thermal shock could cause one to break & that is a very bad thing!
Do your research & homework & have fun!