Author Topic: lost pla/pattern castings ?  (Read 13151 times)

Offline vtsteam

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Re: lost pla/pattern castings ?
« Reply #25 on: July 14, 2018, 06:49:54 AM »
That furnace was built by madmodder Ironman and is already posted here. Picclock, you should read through the metal casting threads here first rather than just asking people to tell you what to do. There are many usable refractories. Asking what you should use to cast is like asking people how to machine. Unless you like to start online arguments. Do your own research first. Then start simple - you said earlier you already had a forge that could melt metal. So start melting. Experience is more important than advice. Show us what your experiences are. Give back.
I love it when a Plan B comes together!
Steve
https://www.youtube.com/watch?v=4sDubB0-REg

Offline awemawson

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Re: lost pla/pattern castings ?
« Reply #26 on: July 14, 2018, 07:33:50 AM »
FORGE = device for heating metals to forging temperatures as would a Blacksmith

FURNACE = device for MELTING  metals usually for casting (unless you are stateside in which case it heats your house  :scratch:)

Andrew Mawson
East Sussex

Offline picclock

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Re: lost pla/pattern castings ?
« Reply #27 on: July 14, 2018, 09:24:28 AM »
@vtsteam
My typo mistake. I should have typed furnace. 

I am not asking people to tell me what to do, merely seeking information about 1 specific part of the furnace, the ceramic wool coating, which does not seem to be available in the UK. I have read many threads about home made refractive mixes, but have not found anyone in the UK to supply a suitable coating as I stated in my post. I note you are in the US, consequently you have access to all of the coatings I asked about. Most home recipes that people seem to have tried appear to be only moderately successful, hence the posted question.

Cannot see why this should cause such hostility. If you never make errors I envy you .. .

Whilst I have refractive firebricks and an excellent propane torch. I would not call it a forge, though that may be my error. I use it for silver soldering. I would not attempt to melt cast Iron with it as the losses are likely too great. Melting aluminium is easily achieved even by accident, as I said.

Best Regards

picclock



Engaged in the art of turning large pieces of useful material into ever smaller pieces of (s)crap. (Ferndown, Dorset)

Offline S. Heslop

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Re: lost pla/pattern castings ?
« Reply #28 on: July 14, 2018, 11:17:17 AM »
Do you mean the zircon paint? It's available, it's just darned expensive.

Here's a google result. https://shop.vitcas.com/vitcas-zircon-paint-coating-687-p-asp.html

Offline vtsteam

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Re: lost pla/pattern castings ?
« Reply #29 on: July 14, 2018, 11:37:18 AM »
FORGE = device for heating metals to forging temperatures as would a Blacksmith

FURNACE = device for MELTING  metals usually for casting (unless you are stateside in which case it heats your house  :scratch:)

He said he had a FORGE, which had become hot enough to melt aluminum once accidentally, so therefore could do some initial simple trial melting in that. Sheesh.  :doh:
I love it when a Plan B comes together!
Steve
https://www.youtube.com/watch?v=4sDubB0-REg

Offline vtsteam

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Re: lost pla/pattern castings ?
« Reply #30 on: July 14, 2018, 12:10:58 PM »
@vtsteam
My typo mistake. I should have typed furnace. 

I am not asking people to tell me what to do, merely seeking information about 1 specific part of the furnace, the ceramic wool coating, which does not seem to be available in the UK. I have read many threads about home made refractive mixes, but have not found anyone in the UK to supply a suitable coating as I stated in my post. I note you are in the US, consequently you have access to all of the coatings I asked about. Most home recipes that people seem to have tried appear to be only moderately successful, hence the posted question.

Cannot see why this should cause such hostility. If you never make errors I envy you .. .

Whilst I have refractive firebricks and an excellent propane torch. I would not call it a forge, though that may be my error. I use it for silver soldering. I would not attempt to melt cast Iron with it as the losses are likely too great. Melting aluminium is easily achieved even by accident, as I said.

Best Regards

picclock


Why would anyone be frustrated with what you're asking? First, I make plenty of errors -- and even wrote about some yesterday, in fact. I actually think you used the proper term, BTW. That was Andrew.

But what you've just said just clearly proved again that you are forming and expressing metal founding opinions with absolutely no experience to back them up. Very familiar ones, too. These have been passed on via the usual internet pseudo-experts who have actually never tried what they disparage and then by repetition by others becomes gospel.

I exclude Ironman totally from that category. He is brilliant. I'm referring to those who think (as he does not) that what he does is the ONLY way things can be done.

Yes, I live in the US with "access" to a few high tech materials if I order them by mail, and if a supplier can be found who wants to deal in miniscule quantities at very high prices, who  is willing to send them. BUT, surprise, surprise, I don't use them. And I do a lot of casting and have done since 2002 when I built my first lathe, and a disk turbine -- with all cast aluminum parts. Hardly anybody was casting online back then BTW, Lionel Oliver was just starting out with Portland cement and flowerpots, and made a few Gingery parts with rough finish.

There are plenty of threads to read about casting here on Madmodder, which would answer many of your questions, and I hope, alter your opinions, if you'd care to look them up. With regard to firebrick being unsatisfactory as a refractory, ridiculous. It has been used traditionally. Please actually read some project threads here, instead of just repeating to the usual web-expert misinformation. I used firebrick in my iron casting foundry furnace, and that was well documented here. I'm not going to link it. Let's see if you can actually find it and read it.

Finally, you started this thread with a request about how you should start with non-ferrous metals. I suggested simplicity -- melt some aluminum with the forge or (or brazing hearth, or whatever anyone wants to call it) you have and get some experience. It is confusing and frustrating to hear that advice completely ignored many posts later with "help me I'm a noob" and then right after read what you believe is a proper refractory which you can't obtain, and how others are lucky because they have access to what you do not.

Melt something. You can do that now, Take pictures. Write about it. Then you've got something real to talk about, instead of surmising what is optimal.

I love it when a Plan B comes together!
Steve
https://www.youtube.com/watch?v=4sDubB0-REg

Offline awemawson

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Re: lost pla/pattern castings ?
« Reply #31 on: July 14, 2018, 12:17:44 PM »
FORGE = device for heating metals to forging temperatures as would a Blacksmith

FURNACE = device for MELTING  metals usually for casting (unless you are stateside in which case it heats your house  :scratch:)

He said he had a FORGE, which had become hot enough to melt aluminum once accidentally, so therefore could do some initial simple trial melting in that. Sheesh.  :doh:

Not having a pop at you (or anyone for that matter) Steve. It's just that I'm on a Welding Forum where people are everlastingly banging on about their Forges whereas what they've built is a Crucible Furnace  :bang:

Andrew Mawson
East Sussex

Offline vtsteam

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Re: lost pla/pattern castings ?
« Reply #32 on: July 14, 2018, 12:52:56 PM »
picclock, heres a very important distinction to keep in mind. Theres a BIG difference between casting nonferrous metals and casting iron.

You can can cast all non-ferrous metals, fuel efficiently, with either charcoal, or propane, in a simple plaster of Paris and sand lined furnace. I am doing just that in my lathe thread. Very very simple, very inexpensive, and very fast...and it produces fine castings -- as fine as you care to produce, depending on your specific methods and materials.

Casting iron is a whole different ballgame. I have a different furnace for iron than I do for non-non ferrous metals. Once again I strongly suggest that you just try melting and casting, using your intended lost PLA process with aluminum, first, using what you have.

I love it when a Plan B comes together!
Steve
https://www.youtube.com/watch?v=4sDubB0-REg

Offline picclock

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Re: lost pla/pattern castings ?
« Reply #33 on: July 14, 2018, 02:22:20 PM »
@vtsteam

My reasoning and requirements are thus :

I would like to cast brass and copper as well as aluminium.

I know that with firebricks and a crucible I will struggle to achieve the correct casting temperature for copper and likely brass.

Consequently a furnace of some sort is desirable, and if I am going to construct a furnace, it would be sensible to have the insulation and burner cast iron rated, because if I am successful with the non ferrous stuff it will be very useful to have that cast iron capability.

 dreams  :med: future stationary engines .. .


@ S.Heslop
Thank you for the link. It is exactly what I needed.  :beer:
Coincidentally the place is in Bristol, where I will be going for the model engineering show on the 17th August. My daughter also lives nearby so that may also prove useful.

Best Regards

picclock
 
Engaged in the art of turning large pieces of useful material into ever smaller pieces of (s)crap. (Ferndown, Dorset)

Offline Joules

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Re: lost pla/pattern castings ?
« Reply #34 on: July 28, 2018, 08:09:46 PM »
The finished pattern got delivered to company, not sure if they will be cast in iron or brass.

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