STL and Fusion 360 source files can be found here: https://bbprojects.technology/collections/stl-fusion-360-source-files/products/bitcoin-model
Video can be found here:
I just recently bought some new equipment (HBM mini lathe and a 3018 cnc-machine) and wanted to do a little project to test out the 2 machines and get familiar with them. So I decided to do a little bitcoin project. I first faced the 2 sides of the 50 cent using my mini lathe. Next I used Fusion 360 to model the coin. The generation of the toolpath and G-code is also done in Fusion 360. The first test I did was in some wood which turned out very nice. Next I switched to the actual coin and after a few hickups and fails I finally found the method to success. This can all be found in the YouTube video I made about the project.
Since I just passes 25K subs I decided to do a little giveaway to show my appreciation to all of you. I really would've never thought I would even reach 1K let alone 25K, so thank you very very much ;-)
I first tried to hold the coin down on the engraving table using double sided tape, but this didn't turn out to be a great idea because the lubricant used for the drill bit dissolved the double sided tape. In the next attempt I used 2 component epoxy glue which worked excellent. Removing the epoxy glue turned to be pretty easy. I used a 25 degree, 0.1mm tip engraving bit, they did brake from time to time but lowering the engraving speed helped a lot.
I used this model to engrave a bitcoin patern onto a coin but you can also use the STL-file to print it out using your 3D-printer. You might have to scale it up a bit to reach to desired detail.
I tried to work as safe as possible with the mini lathe (no long sleeves, removed watch, closed safety covers, etc...) but I do realize working this close to the chuck might not be the best idea, so I wouldn't recommend you doing this.
Some might note I'm "destroying" money. this was also one of my main concerns when I started this project so I did some research. This is what I found on the website of the National Bank of Belgium:
"When notes or coins are definitively withdrawn from circulation, one is not punishable. This is the case, for example, if they are incorporated into souvenirs, decorative works or works of art in such a way that they can no longer be returned to their original state."
I also send them an email just to be sure but I guess this isn't even worth their time because they just keep redirecting me to other departments and it has been a few months now since I've heard from them. but we should be good ;-)
25 degree, 0.1mm tip engraving bit: https://www.banggood.com/5Pcs-Pyramid-Engraving-Drill-Bit-3_175mm-Shank-25-Degree-0_1mm-Tip-for-EleksMill-Engraver-CNC-Router-p-1273127.html?p=E01411629100201406T1&custlinkid=1403609
HBM 180x300 metal mini lathe: https://www.hbm-machines.com/producten/hbm-180-x-300-metaaldraaibank-met-digitaal-display