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Re: Were Third Reich badges ever cast?
Funnily enough ( and not wanting to be pedantic ) but the circular marks are from EJECTORS - these push the part from the die when the 2 halves open. The INJECTOR gate is quite small and usually it takes a trained eye to see where it is.
Cheers, Dan - expert in useless knowledge
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06-11-2012 03:11 AM
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Re: Were Third Reich badges ever cast?
Yes, you're correct Dan, I should've made it clear that the ejector marks are usually found on the injected badges so you can tell the method of manufacture because of this.
Looking for LDO marked EK2s and items relating to U-406.....
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Re: Were Third Reich badges ever cast?
You blokes are a wealth of knowledge, I never tire of reading threads like this!
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Re: Were Third Reich badges ever cast?
Being a toolmaker / engineer can be a lonely existence - this stuff is not exactly a dinner conversation starter!!
BUT, if you want another dose of trivia, here goes .........
Aside from Stamping, badges WERE cast - and casting comes in 3 main forms...
- SAND CAST ( where the mold is resin bonded sand and the molten metal in poured in and the sand broken away - this is what was used for large castings like tank parts and gun carriages etc... ) where the size of a permanent die is prohibitive or the shape is complex but the detail is not.
- PERMANENT MOLD / gravity ( where the die is in two halves and the metal is poured in and allowed to cool before removal ) Simple rubber dies can be open to the atmosphere ( i.e. ONE half only ) but as the material cools, the imperfections will settle to the surface and this is why the cheap fakes look rough on the back - the "dross" forming there will look like bubbles and blemishes.
- PRESSURE DIE CAST ( where the molten material is injected into the die - this allows for high definition of the part and controlled cooling and grain structure formation )
Even a 2 part mold gravity cast badge will have "softer" finish than a pressed ( stamped / coined ) or PDC ( injected ) badge - this is because allowed to cool naturally, the gravity casting will shrink away from the details whereas a stamped or pressure cast one will have sharper features as the material is forced into the impression and held there as the initial cooling occurs.
See, I told you I would rabbit on, given the chance!
Cheers, Dan
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Re: Were Third Reich badges ever cast?
Nice that you know the 'ins-and-outs' of the different
casting methods, Dan.
One thing not mentioned yet, is that when a medal
or badge is copied by making a mould from an
original, the result is a slightly smaller
product.........
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Re: Were Third Reich badges ever cast?
by
Walkwolf
Nice that you know the 'ins-and-outs' of the different
casting methods, Dan.
One thing not mentioned yet, is that when a medal
or badge is copied by making a mould from an
original, the result is a slightly smaller
product.........
Absolutely correct Steve! ......another good thing to look out for even though it may be less than 2mm in height, they DO SHRINK.
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Re: Were Third Reich badges ever cast?
Hello Dan,
the information that you have posted is quite informative and helpful but can you enlighten me as to the two casting techniques that are used using centrifugal dies (ie spinning dies that produce wafer thin badges) and the other innovation of passing an electrical current through a die to attract the metal.
I believe that these two methods are currently being used to produce the very high quality fakes that are beginning to appear.
Any info would be greatly appreciated.
All the best
Doug
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Re: Were Third Reich badges ever cast?
by
Saladin
Hello Dan,
the information that you have posted is quite informative and helpful but can you enlighten me as to the two casting techniques that are used using centrifugal dies (ie spinning dies that produce wafer thin badges) and the other innovation of passing an electrical current through a die to attract the metal.
I believe that these two methods are currently being used to produce the very high quality fakes that are beginning to appear.
Any info would be greatly appreciated.
All the best
Doug
Hi Saladin & Adrian,
Spin casting ( or centrifuged / rotary molded ) is a relatively new process for me also. I know it mainly from plastic construction ( compost barrels, water tanks- that sort of thing ) Large parts are rotary molded because again, like sand casting, the die costs are low. Polymer powder is placed in the die, & melted as the heated dies are rotated and the material forms a uniform coating on the die surface. Allowed to cool, the halves are unbolted and the part removed. Not sure how a badge can be made this way though???
The electrodeposited method is usually relegated to plating where the part to be plated ( the cathode ) is placed in an electrolyte bath along with a bar of the material to be deposited ( the anode ) UNder an applied current, the electrons will flow from the anode to the cathode and bingo, you have zinc plating ( or nickel, or silver, or tin etcc.. ) This deposit is microns thick and I'm not sure how this method either can be used to make badges........ I will have to do some research & get back to you.
There, that wasn't too long an answer, was it?
Dan
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Re: Were Third Reich badges ever cast?
Hello Dan, thank you for the comprehensive answer.
I believe that both methods are currently being used in Birmingham to cast super reproductions of badges.
Using the 'electrified' moulds the badges lose very little or none at all of the original sizing and details of the original cast (or so I am led to believe from the chap who wanted to borrow some of my badges to cast)
I understand the principal of plating but from what I can gather it is only the mould that is charged and the metal particles (Powdered metal?) already have an electrical charge and are attracted to the mould giving and even coating all over.
I do not think that the thickness would be a problem as it would depend on the amount of powder used....Don't really know as I am too thick to understand the technical side.
On the rotational moulding I do understand what you mean about moulding plastics but when I approached one foundry in Leicester they were happy to do sand cast mouldings that are spun to spread the moltem metal over the surface of the mold. I didn't go down that route in the end but just had the bog standard sand casting done,
Quite suprisingly the cast piece measuring about 6 inches tall (a large SS Skull) was only very fractionally smaller than the original piece.
I look forward to your findings after you have done a bit of research as I can find out very little information
Very many thanks
Doug
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