Injection molding PC, Acrylic and Ultem lenses

[DustyRhodes]

I am developing a small micro lens part. The shot size is .15 gr. PEI and my smallest available injection machine is 14T 18mm 20gr (PS) screw. Because the part has very fine features it is necessary to raise melt temps toward upper range limits. This presents a less than ideal scenario where, I believe, residence time is causing some degradation and introducing small black specks within the part. Some may be in the light path were they could be problematic. Does anyone have some sharable experience with this. I know the obvious recommendation would be to size molding machine more appropriatly for the part and I believe that will happen once parts and designs are qualified and production bound. I need to get to that point from here. Thanks for your thoughts and advice.

 

[dgallup]

I've heard of people putting extra volume in a throw-a-way portion of the tool. It wastes material but that is OK if it's just for proof of concept.

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The Help for this program was created in Windows Help format, which depends on a feature that isn't included in this version of Windows.

 

[MikeHalloran]

Yeah, big tree/ small part.
OR
Make the throwaway cavity produce something you can give away at trade shows and such.
- business card
- pocket magnifier
- bottle opener
-






Mike Halloran
Pembroke Pines, FL, USA