As someone who will probably needs custom insoles as my foot keeps getting worse and has started causing backpain but is still growing quite quickly which mains they would need to be replaced every year or so. I ended up researching 3d printed foot orthodics, loosely following a guide from instrutables as well as taking other bits of knowledge I found I started making a mold out of playdough, next I will 3d scan it, make any modication nessesary in meshmixer and print in a tpu