Information regarding "Collapsible core" in Injection molding 1

[reswam]

Dear All
Any body have information/links regarding "Collapsible core" using in injection molding like
What is the tool cost?Is it increases or decrease?
What are the disadvantages/limits using this for internal undercuts for PC material
What are the advantages of collapsible core
Thanks

 

[patprimmer]

Collapsible cores are complicated and expensive, and are only used where there is no alternative like eliminating undercuts, changing parting line angles, jumping moulding off the core etc.

Polycarbonate is very inclined to stick on cores, and will not jump over any substantial undercut, so if you can't design to eliminate or minimise the undercut, you might need a collapsible core.

Advantages.

They make otherwise impossible mouldings possible.

Disadvantages.

Cost increased.

Cycle time increased.

Opening stroke increased.

Maintenance increased.

Core cooling more complicated and probably more fragile.





Regards
pat pprimmer@acay.com.au
eng-tips, by professional engineers for professional engineers
Please see FAQ731-376 for tips on how to make the best use of Eng-Tips Fora.

 

[patprimmer]

If the collapsible core is for the snap fit in another thread, then collapsible cores are NOT necessary if the socket is designed correctly, as illustrated in most high profile raw material manufacturers literature

Regards
pat pprimmer@acay.com.au
eng-tips, by professional engineers for professional engineers
Please see FAQ731-376 for tips on how to make the best use of Eng-Tips Fora.

 

[reswam]

Thank you very much pat