I started experimenting with 3D printing hammers back in December of 2023. I soon had working flexible hammers that sounded great at multiple lengths. 10" and 8.75". As of July 2023 I have been experimenting with a rigid design but those are a lot more difficult to make. The PLA plastic that I use is very durable, but do not leave it in a hot car or direct sunlight otherwise they will warp. It's a good idea to treat them the way you treat your Dulcimer. Visit my facebook page to inquire about ordering a pair of hammers. www.facebook.com/ians3dhammers