I want to use ERPNext to keep a track of the costs of different builds of machines. Say for example, I have 3 machines to build and I raise a purchase order for some bought out parts for these machines from a supplier. These parts will then be received in to stores, and subsequently issued to the 3 jobs. How do I assign theses parts to the jobs so that later on I can simply ask ERPNext what the material cost was for each of the machines? What I would like to do (and have done with other ERP systems) is to assign a job number to the parts at the time of issuing from stores. Then is simply a case of adding up all the costs associated with that job number. Does ERPNext do this but in a different way?
The “Production Order” seems to work very well when you know exact items that are going to constitute the whole job. Suppose you are repairing a truck and initially you have planned to spend 1 week on the truck with known parts to be used and you have created a BOM using this information. During the middle of the job you then realise that the hub on one wheels needs replacement, the left front tie rod also needs replacement, and there is crankshaft bracket needs replacement. You want to add these items to your initial production order. Do you create another BOM that incorporated these items and add the new BOM to the running production order. The client must get one invoice when the truck gets out of your workshop. The extra work may extend job duration from initial one to two weeks with one week in March 2018 and the second in April 2018