Artificial fingernails for classical guitar

My fingernails break often, but I didn’t find generic artificial fingerpicks adequate.

PATH TO A SOLUTION: Create a 3D scan of the fingers, then build a 3D printed, made-to-measure design around them.

PROBLEM 1: Acoustic properties of the nail need to be addressed:

* Softness & springiness
* Friction with string
* Internal structure

SOLUTION: Separate the nail from the base. Flat printing gives the best internal texture and boundary texture. Moreover, it allows for a flexible choice of materials: Recall the Shore scale of 3D printing materials:

* PLA: 80D
* PETG: 76D (Ultimaker data sheets)
* FiberFlex: 40D (Fiberlogy data sheets)
* Equine hoof (keratin): 70D ([https://www.researchgate.net/publication/324722739_Nail_Properties_and_Bone_Health_A_Review](https://www.researchgate.net/publication/324722739_Nail_Properties_and_Bone_Health_A_Review))
* Foot sole: 30D ([https://doi.org/10.1016/j.foot.2012.01.003](https://doi.org/10.1016/j.foot.2012.01.003))

Friction: T