Let's look at in another way. Let's say you need a PT to build a house.

The player click on the "lot" and select what part of the house they are going to craft. Frame, windows, roof/walls, metal materials, etc... The players continue craft the varies pieces until everything is done.

Honestly alot of the items in the game could be party crafted. Look at the mats for a simple sword. You need a blacksmith, leatherworker, alchemist, and goldsmith.

I'm took tired right now but tomorrow i'll make a well thought out post about a party crafting system that works for everyone.