Author Topic: A new way of casting aluminium (to me anyway)  (Read 2109 times)

Offline Admiral_dk

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A new way of casting aluminium (to me anyway)
« on: January 20, 2018, 07:10:06 PM »
I had this interesting 16 minute video suggested to me by Youtube -

I must admit that it is a very nice way of making moulds, a fast turn around and very precise result - but I would really like to know what it is they "paint" the polystyrene moulds with, before pouring sand around them.

No I 'm not going to be casting myself.

Offline fumopuc

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Re: A new way of casting aluminium (to me anyway)
« Reply #1 on: January 20, 2018, 07:53:27 PM »
I will try to explain, what I have learned in our foundry.
At every casting process a kind of barrier layer is necessary betwen the sand and the metal.
In this case the foam will be coated to the get the barrier in place.
The hot aluminium burns the foam out and the "paint" still stays between the hot metal and the sand.
The German word is "Schlichte" in Englisch languages I know only the word coating may be a native speaker can help with the right translation.


PS: some more Information just seen


https://www.giessereilexikon.com/en/foundry-lexicon/Encyclopedia/show/facing-coat-3203/
« Last Edit: January 20, 2018, 07:57:24 PM by fumopuc »
Kind Regards
Achim

Online Jasonb

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Re: A new way of casting aluminium (to me anyway)
« Reply #2 on: January 20, 2018, 08:01:26 PM »
It is a liquid plaster that coats the foam and gives a better surface finish than if the sand were packed directly around the foam. As it also forms a thin shell the sand does not need to be rammed around the part so hard.

I the home foundry you can dip it into drywall mud a couple of times to get the same effect.

Online Vixen

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Re: A new way of casting aluminium (to me anyway)
« Reply #3 on: January 20, 2018, 08:03:24 PM »
Over in UK it's known simply as ceramic slurry. Does not sound as exciting or descriptive as the German word.

Mike
It is the journey that matters, not the destination

Offline fumopuc

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Re: A new way of casting aluminium (to me anyway)
« Reply #4 on: January 20, 2018, 08:17:49 PM »
Yes, thanks Mike,  ceramic slurry, that was it I could not remember.
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Achim

Online Vixen

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Re: A new way of casting aluminium (to me anyway)
« Reply #5 on: January 20, 2018, 08:25:15 PM »
"Schlichte" I like the sound of that much better

Mike
It is the journey that matters, not the destination

Offline Admiral_dk

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Re: A new way of casting aluminium (to me anyway)
« Reply #6 on: January 21, 2018, 08:36:48 PM »
Thank you for the answers gentlemen.

Quote
Over in UK it's known simply as ceramic slurry.
- though I understand the German word just fine, it doesn't tell whet it's made from - whereas the English term is the same compound used by the "potters" to me. I might be wrong here though.

Jason, that sounds like a cheap solution.

But as earlier stated - I have way too many projects and absolutely not enough time for the majority of them .... so casting is not in the cards for me.

Offline fidlstyks

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Re: A new way of casting aluminium (to me anyway)
« Reply #7 on: February 22, 2018, 02:08:24 PM »
This is a process I need to learn. i estimated I have cast over 20 tons of iron since 1980. Always pouring some aluminun and brasses.  I really like the diversity I see here.

Offline tinkerer

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Re: A new way of casting aluminium (to me anyway)
« Reply #8 on: March 08, 2018, 07:09:34 AM »
For at home use. I'd be wondering about the fumes given off by the foam. It is a type of plastic. Basically It looks to be similar to lost wax casting. Using a similar type of plaster surface against the foam as you'd use in lost wax.
You never know what you can do, till you try. Don't be afraid to try & fail. We learn more from our failures than our successes.