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Need to choose material for display product

Need to choose material for display product

Need to choose material for display product

(OP)
I have designed and will produce a part which is specific to the display industry for watches. I need a material for what we call a watchcuff. You see them in all retail stores where watches are sold. The watches are placed on the cuff to be displayed standing vertically in the showcases. The material must have stiffness or spring to it to allow watch size variation in the bands, be clear or at least frosty translucent.
We tried ABS, not so much for its spring, though it has some, but because it was flexible enough to allow the cuff to be opened up to fit the large men's watch sizes or squeezed to fit the small ladies size watches. ABS was not so good as it does give off a slight smell which becomes noticeable in a closed, warm showcase. Also, not clear.
I have produce many of these cuffs using clear polycarbonate as the material. Polycarbonate has a few problems as well. Though it is tough and flexible it seems to get briitle over time. It also discolored or was  effected by the warm temperatures in the showcase or the bright halogen lighting. Eventually the polycarbonate cuff snaps and breaks.
I have thought about acetal, polycarbonate/abs alloy, cellulose acetate, Pet, PetG as canidates, but would like to know which has the charactoristics I am looking for without doing a lot of testing.

RE: Need to choose material for display product

LDPE sounds good to me. Thin enough and it is flexible. Does't smell unless its burnt.
Coincidently, I have just bought a rotational molding machine that is great for LDPE. Low cost tooling for medium to low quantity production runs.
What are your quantities. I will not have the machines up for a few weeks but as of right now we have free time on them. www.polysort.com has a good forum for rotaional molding, if you'ld like to check into it.

RE: Need to choose material for display product

I would try UV stabilised PC, it is probably the sunlight that is making the normal pc brittle.
PC is also notch sensative, so if the surface quality of the part is not so good manipulation can cause a problem.

One other material to try would be SAN, which is like ABS but it is clear.

RE: Need to choose material for display product

Hey, I agree with chaving.  PC is very suseptible to UV light and under those conditions it is well known to degrade over time.  This behavior can be fixed with the addition of a stabilizer, but you will need to specify to your supplier that you need it.  GE offers a UV stabilized version that will work great.  Also, clear PC can be slightly tinted with a very faint blue color that gives it a GREAT look!

John

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