MIM question

[PedroArrochella]

hi, i´m doing a metal injection mold ( new to MIM, 90% of my work is plastic!!) and i´m having a lot of problems in calculating the runners for the mold, any sugestions?

best regards
Pedro Lobo

 

[Pud]

Hi PedroArrochella,

I would guess as the binder is a polymer (usually POM), so you are just moulding heavily filled plastic. I would suggest the usual rules apply - e.g. full round runners, minimum 6mm dia, gates 75% of wall thickness and feed onto thickest section. If base polymer is POM then you will also need to have plenty of heating channels to ensure even heating and hence minimum warpage. Good idea to insulate clamp plates also as tool needs to be around 90 deg C. or above.

Have you tried contacting raw material supplier? They will probably have heaps of information.


Rgds

Harry

 

[PedroArrochella]

Thanks for the info, Harry.I´ve came across some manuals from buhler that were also very helpfull.
best regards
Pedro Lobo