07-31-2014 01:25 PM
I'm looking for injection-compression mold designers to making counseling. I have optical part designs. I want to manufacture them.Could you please help me?
Looking for Injection-compression mold consultants
07-31-2014 03:50 PM
How large is your parts and which material have you selected ? Are you considering Injection/Compression to eliminate Birefringence ?
07-31-2014 06:45 PM
My parts dimensions 92mmx 117mm.Parts thickness is between of 1.7mm and 3.2mm and about 30grams weight.I select PMMA because of UV resistance.I made moldflow analysis and there was sink mark areas on optical surfaces. I guess I have to make compression-injection mold.
07-31-2014 08:54 PM
Erdem, There are 2 basic types of IC processes, 1) Open Parting Line and 2) Telescoping Core Inserts ( sometimes called coining). The open Parting Line process is usually used for very fast cycle times---like for CD's. The actual shot is precisely metered and performed before the mold is fully closed and relies on a slightly opened PL to act as a full vent and some material to be squeezed out. Since the final packing is a result of the compression of the tool---and not gate/injection pressure----the birefringence is at a minimum. I have worked with Lens manufacturers that use this process and multiple Inserts for the various lens optical thicknesses/curvatures. The best part/tool designs I have been involved with use a 75mm round molded part with a large Tab Gate feeding the material. The actual finished Lens is mechanically routed about the center of this 75mm coupon on NC routers to the desired final size/profile. This molding process has the best results for elimination of birefringence and enables the variation in types of profiles----especially for Eye Glasses that have numerous profile shapes. The closed PL process with telescopic core inserts will not accomplish a lens grade part-----especially if you are thinking of molding the Lens at the finished size.
07-31-2014 11:11 PM
Mark, thank you for your reply.