This is the review saying that you can dent your fretboard if you are not careful with the Stretcha. Maybe he is a brute
https://www.guitaranswerguy.com/002/
The tensile strength, density and strength to weight of epoxy (Stretcha) and ABS (3D printer material) is not very different. I don't think that it would break.
The cheapest one I've found that ships to Thailand (from Ebay Japan) is $40.97 inc shiping. I'll start with the design during the spare time at the office. There is no rush, just for fun. In the meantime, I'll keep doing like
@Joe Bfstplk but without breaking the strings