Melinex alternatives
Melinex alternatives
(OP)
Forum:
First, I'm not sure if this is the right forum to post this in, but I figured I'd give it a shot.
I'm working on a product right now that has a Melinex 515(1000 gauge) backing with felt stuck to it, using a double sided tape. The part slides back and forth over a metal shaft, lubing it as is travels back and forth.
The current process to make them is we cut the three layered part to size(35x35mm, about 1 3/8"x 1 3/8"), roll them over a mandrel and insert them into a drilled out hole, resulting in a tight fit. We then heat them up to 160C(320F) in an oven for 15 minutes and after they cool we remove them from the jig.
The result is a tubular shaped part, that holds it's shape pretty well.
Working temp and stresses are unknown since this is the early stages of design. This is the next thing I need to look into.
What we're looking for are Melinex 515 alternatives. Cost is an issure here, so cheaper=better. Using heat to form the part is fine but again, lower temps and shorter times would be nice. Or would baking the part for a shorter time work?
The part needs to hold it's tubular shape, and from the few of the people I have called it seems like Melinex 515 might be the best way to go.
I appreciate any help, and look forward to reading your responses.
Darren
First, I'm not sure if this is the right forum to post this in, but I figured I'd give it a shot.
I'm working on a product right now that has a Melinex 515(1000 gauge) backing with felt stuck to it, using a double sided tape. The part slides back and forth over a metal shaft, lubing it as is travels back and forth.
The current process to make them is we cut the three layered part to size(35x35mm, about 1 3/8"x 1 3/8"), roll them over a mandrel and insert them into a drilled out hole, resulting in a tight fit. We then heat them up to 160C(320F) in an oven for 15 minutes and after they cool we remove them from the jig.
The result is a tubular shaped part, that holds it's shape pretty well.
Working temp and stresses are unknown since this is the early stages of design. This is the next thing I need to look into.
What we're looking for are Melinex 515 alternatives. Cost is an issure here, so cheaper=better. Using heat to form the part is fine but again, lower temps and shorter times would be nice. Or would baking the part for a shorter time work?
The part needs to hold it's tubular shape, and from the few of the people I have called it seems like Melinex 515 might be the best way to go.
I appreciate any help, and look forward to reading your responses.
Darren





RE: Melinex alternatives
Melinex used to be an ICI trade name, and Mylar is the Dupont equivalent. I am sure there will be others.
The 515 designation might indicate variations on raw material used, colour, surface finish, or things like flame retardant or anti-static.
From you description of the application, it sounds like straight biaxially oriented PET would do the job.
If you do a google search for Mylar and foe biaxially oriented PET, you should find another source.
Oriented PET is very crystalline for a semi crystalline thermoplastic, and the temperature of 160°C will be quite critical to thermo-form it.
PET does absorb moisture from the atmosphere, and does hydrolyse if heated while containing water. If heated above 100°C, out-gassing can also result in a pimpled surface with a feature like a microscopic volcano.
If this is a problem, you might need to dry it according to the manufacturers recommendations, which I don't presently have at hand, but of which I am sure you can obtain on request from your supplier or the manufacturer.
Regards
pat pprimmer@acay.com.au
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RE: Melinex alternatives
RE: Melinex alternatives