See similar issue on Silent's Gems (SilentChaos512/SilentGems#334)

The mod might benefit from some way to salvage tools and armor that are no longer needed. I have not had a chance to test this myself, but uncrafting tables apparently do not work in Gems, and the same is probably true for Gear. That isn't surprising considering how the recipes work, there is nothing for the other mod to make sense of.