Hi again all,
Well and truely been there done that and got the T shirt now so i thought i feedback for everyone elses benifit.
MP drawings are in addition to the assy drawing and consist of front sheet with iso view of part showing the datum / support structure used to hold the part in measurement etc. This is normaly as the part is fitted to teh car as i understand it.
Further pages show the part and identify specfic POI that are called off using a code. Next to this is a reference table with the co-ordinates of said points.
These are programmed to the CMM in a special program that can be read by volvo system. You measure the part to this, load the results up to the web (txt files and very very hard to alter unless you are good at code) and then Volvo can see exactly where you parts are in relation to every component int he vechile!!
Now this is the really clever bit, if you are showing a consistent product that is off to one side of teh tolerence band (hence not a good Cpk value) they can look at the area and the vehicles they are building and if it dosent affect them they tell you not to move it! rather than spend ages tuning your part for no reason, equaly (i work with BIW and closures) if a panel needs you hardware matching to it they may ask you to move your part within the tolerence band using new target co-ordinates!
sorry for the long post but hope it is useful!