mold processing question

[Trapper Paul]

Here's one! Guesss what they have the toolmaker (me) out at the press trying to run a mold.

I'm running a 2 cacity mold in a shuttle press. It's small part each part is .7 grams and the runner is about 2 1/2" long. The part is poly carbonite (PC). any idea's where to set the fill at? pos. PSI, and time?

 

thanks, sorry its off topic. Paul

[Kevangel]

Are there set up sheets from last time you can ask for, or some from a similar part since your work is (or atleast looks) inter related?

[Trapper Paul]

We typicaly run a low pressure PVC, PP, etc.

So all the set up sheets reflect a zero value for fill and hold positions, PSI and time values. We fill by turning the screw and (for lack of a better word) uze it in slowly so we don't damage the cables/wires/resistors, etc.

[Scott B]

What kind of machine is it and is it a hyd or electric press?

[Trapper Paul]

Newbury 30 hyd. shuttle press's

[Scott B]

PC I believe needs to be filled as fast as possible. Depending on the part will also determine what if any pack and hold is needed. Don't over pack the mold.

We always started at a non fill point and worked in more material until it filled then started with the pack and hold to get the best part possible. That of course was with a new part that had never been processed.

[Trapper Paul]

any idea what numbers where taking....?

fill PSI 2,500-5,000-10,000 time = 2 sec's?

hold same questions

[Scott B]

I would start at around 1000-1200 PSI @.7 grams for your part I'd say 2.0-2.5 sec fill time. I should have asked how big of a shot does your machinie have or barrel dia? This could change the above numbers.

[Trapper Paul]

barrel dia. is about 1.250" I'm not sure about the shot size but it's not that big and we have the opposite problem, we are only ussing a small amount of plastic, so it's hard to process in because of the small size.

 

Thanks I'll check back later gotta run