# Two Coins Second Attempt



## lazersteve (Mar 13, 2011)

After fabricating a second set of molds I made an second attempt at casting some coins shaped blanks. 

These two guys have been cast into a 7/8" diameter x 1/8" thick graphite cavity and the sprues and flash are mostly trimmed off:







I melted the gold using a standard MAPP torch.

They are destined for the rolling mill next to get them a little thinner and smoother with final trim thereafter. Lastly, I'll stamp them 'Fine Gold' with my new set of lettering punches. I may go the extra mile and throw them on the marking laser, but I'm skeptical if they will look ok etched instead of embossed. 

I'll post more photos as the 'coins' take shape.

Each of the coins weighs around 28 grams. I was hoping they would turn out ~31 grams, but all in all I'm happy with the results so far.

Steve


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## lazersteve (Mar 13, 2011)

I managed to get one of the 'coins' run through the rolling mill and run through my polishing media. 

Here's it is next to the second one:






I'm very happy with the way it turned out, except for some very tiny surface bubbles that can be seen under a 10x loupe.

Next stop, stamping and possibly etching.

Steve


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## glorycloud (Mar 13, 2011)

Very nice Steve. Congrats!


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## samuel-a (Mar 13, 2011)

Very nice Steve.
Thanks for the pictures.

May i suggest, instead of pouring in to a round shape mold (with all the hassle around it), you could just pour as usual a rectangular bar, roll it in the mill to desired thickness and use a set of round punch press tools to create your 'coin' easily and with a minimal need for final touch up.

One of my acquaintance prepare his blanks just like that, blanks are to be stamped later. He is doing everything manually on a small scale.
One of my favorite things thought, is, that annealing is not needed for pure gold at any step of the process.

Good luck, Sam


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## lazersteve (Mar 13, 2011)

samuel-a said:


> Very nice Steve.
> Thanks for the pictures.
> 
> May i suggest, instead of pouring in to a round shape mold (with all the hassle around it), you could just pour as usual a rectangular bar, roll it in the mill to desired thickness and use a set of round punch press tools to create your 'coin' easily and with a minimal need for final touch up.
> ...




My circle punch does not have a large enough diameter cylinder to make this sized coin. Even if it did I would probably do it the way I am. If I were going to mass produce them I would invest in the proper equipment to punch out the larger sized disks, but at this point I just tooling around with the gold trying to learn more about making coin blanks. 

I have used my punch set to make some smaller silver coins, but they are too thin due to the thickness limits of the punch I have.

Steve


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