How to avoid the CONTRACTION VOIDS??? 1

[pontvi]

Could anyone help me to improve my injection process?
We are talking about a thick part, made of nylon with glass fiber. Once injected, in the surface it seems to be well compacted but in the interior there are "bubbles".

At first sight I tought they were air traps, but reading injection manuals and courses, now, I think they are CONTRACTION VOIDS.

If anyone know how to improve this problem, it would be very good to me. It's a hot runner injection part. It's injected with 6 gates in the core (I mean the thickest part of the piece), but I'm not able to eliminate these voids.

Thanks in advance.

 

[Pud]

I would suggest you try your current supplier of nylon - mineral filled nylon is a common material.

Your location would be useful to recommend suppliers...

Cheers

Harry

http://www.tynevalleyplastics.co.uk

 

[patprimmer]

pontvi

There comes a point where you have to demonstrate that you also are doing your share in finding this information.

Mineral filled nylons are available from a huge range of suppliers. I am sure you can find one in your region. They will most likely also provide recommendations about moulding conditions and troubleshooting.

Regards
Pat
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