Need Hard Durable material for use with living hinge?
Need Hard Durable material for use with living hinge?
(OP)
Im not sure if such a material exists, but I need a hard durable material such as polyacetal that can be used with a design including a living hinge. Any suggestions would be greatly appreciated.
Thanks
Mark
Thanks
Mark






RE: Need Hard Durable material for use with living hinge?
The live hinge principal works because the linear molecules align themselves fairly accurately across the hinge, parallel to each other and perpendicular to the axis of the hinge. This arrangement is instigated by flowing the material through the narrow gap that is the hinge, then it it enhanced by stretching the semi molten material (before the material is crystallised to a significant degree), by flexing the hinge as the mould is opened.
Synthetic fibres are also formed by stretching the polymer as it freezes, thereby aligning the molecules in the direction of the axis of the fibre. I would presume that any plastic that makes good fibres would be reasonable for making live hinges, but I acknowledge that PP is best at this.
Regards
pat pprimmer@acay.com.au
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RE: Need Hard Durable material for use with living hinge?
From experience PP is much too soft and Polyacetal works best for this application, but it is too brittle to mold a hinge.
Thanks
Mark the Coop
RE: Need Hard Durable material for use with living hinge?
I guess you already have a mould that has done PP and acetal.
If it moulds both of those materials, it should mould Nylon OK.
I would try type 6 first as it is easiest to mould, if it is to soft, try 6.6.
both should be unfilled, and moisture conditioned after moulding, but before use
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.
RE: Need Hard Durable material for use with living hinge?
Have a look here:
http://engr.bd.psu.edu/pkoch/plasticdesign/living_hinge.htm
All you need to know I think......
Rgds
Harry
RE: Need Hard Durable material for use with living hinge?
it is being printed to be included in my hard copy information system as I type.
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.