The problem you can not make a tag or topic with a number as first letter. It would be great if admins can find a solution or manually create one. There is a great huge community around open source printers what would be potential users.
Thanks for supporting that feature - I have no clue where I can ask for it other than here as I am pretty new on steemit. So would be great to get the topic set up maybe manually by an admin!
I try to write a whole 3d printing tutorial at stemmit - you can find it here: