The way our manufacturing floor is set up, we have sheet metal parts that go through multiple work orders: Cutting, sanding, bending and powder coat. In Odoo, we would like this to be one part that has multiple work orders, and returns to inventory between steps. Aka the sheet metal is cut, then is placed into inventory, then sanded and placed into inventory etc. We currently have this set up so that a new part is made from the previous part after a work order is completed and this makes the BOM huge and it is extremely time consuming to make new products in Odoo when each sub assembly has multiple work orders it has to go through. 

Current setup example: Sheet metal is cut and makes PN-123, 10 of 20 of PN-123 are sanded and becomes PN-321, then PN-321 is bent and becomes PN-111 etc. Where each step in the work order is a different part/product in Odoo

I know that one step manufacturing can be used where it goes through multiple work orders till the part is finished. The problem is that often parts will be processed all the way up to the powdercoat or bending work order and then sit in inventory for a while. This will show that the amount of finished available parts is 0 for the full assembly, and a new manufacturing order will be made when an order is placed, even though there are parts that are one or two steps away from being finished and could fulfill that order. 

Is there a better way to set this up so that products can return to inventory between work order steps without each step in the manufacturing process being a "new part/product"?