The Tricky Bits – Changing Colors

When you quote a job there is usually a standard setup fee buried into the part price.  This covers hanging the mold and changing the material.  Most schedulers and molding technicians know that in a perfect world jobs are scheduled with low temperature light colored materials first then the high temperature dark colored materials last.  Too bad the world isn't perfect.  Many times you'll have a job in black ABS then the next one in clear crystal styrene or snow-white polypro or something.

Changing materials and making mixed colored parts is very expensive – you can't use the regrind, you lose machine time, the odds of a reject are quite high.  If you have a part (relatively high volume) with VERY PICKY cosmetic requirements about black specs etc. think about this:  Why not buy an extra screw/barrel combination for only that material?  Changing a screw and barrel is about a two-hour job.  This easily offsets a few days of scrap.  Spendy? Sort of.  It cuts scrap on this particular job and is a spare you can swap in if you break a screw tip or damage a barrel.  Having a spare on hand is always more profitable than not being able to use a press.  Think about it.

Call with questions
Bill Tobin – President WJT Associates
wjtassociates.com
303 604 9592