Best way to cut ePTFE sheet laminated to a polyester/polyethylene backer
Best way to cut ePTFE sheet laminated to a polyester/polyethylene backer
(OP)
Hello,
So I'm having trouble cutting a thin (<1.5mm thick) sheet of expanded PTFE laminated to a polyester/polyethylene backer. The kicker is the sheet is half an inch wide and I'm tying to cut circles with a diameter of .4 inches. I'm using a cutting die, but am experiencing tearing of the backer instead of the desired clean cut. Any suggestions? Would shearing the cutting die or increasing the tension of the strip help create a cleaner cut? Any help would be greatly appreciated.
Thanks,
G
So I'm having trouble cutting a thin (<1.5mm thick) sheet of expanded PTFE laminated to a polyester/polyethylene backer. The kicker is the sheet is half an inch wide and I'm tying to cut circles with a diameter of .4 inches. I'm using a cutting die, but am experiencing tearing of the backer instead of the desired clean cut. Any suggestions? Would shearing the cutting die or increasing the tension of the strip help create a cleaner cut? Any help would be greatly appreciated.
Thanks,
G






RE: Best way to cut ePTFE sheet laminated to a polyester/polyethylene backer
A hot knife might do better.
Dipping the material to be cut into liquid nitrogen should help, but hardly worth the trouble I would expect
Regards
Pat
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RE: Best way to cut ePTFE sheet laminated to a polyester/polyethylene backer
-G
RE: Best way to cut ePTFE sheet laminated to a polyester/polyethylene backer
RE: Best way to cut ePTFE sheet laminated to a polyester/polyethylene backer
If that didn't help, and probably anyway, I'd send it out for laser cutting. (Which may not work, depending on the color of the material and the laser wavelength.
If that didn't work, I'd send it out for waterjet cutting.
(I'd do it in that order because, if it works at all, I suspect the laser would give you a better edge finish.)
Mike Halloran
Pembroke Pines, FL, USA
RE: Best way to cut ePTFE sheet laminated to a polyester/polyethylene backer
-G
RE: Best way to cut ePTFE sheet laminated to a polyester/polyethylene backer
One thing that may allow your shear die to work better is to cool your film so it will be more brittle and not stretch at the cut. A compressed air Vortec cooler or a shot of liquid CO2 may work.
RE: Best way to cut ePTFE sheet laminated to a polyester/polyethylene backer
Now I am not quite sure what you mean by polyethylene/Polyester as they are quite different materials and are not normally sold as alloys as far as I know.
Regards
Pat
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RE: Best way to cut ePTFE sheet laminated to a polyester/polyethylene backer
RE: Best way to cut ePTFE sheet laminated to a polyester/polyethylene backer
Ugh. That might be an insurmountable problem. Can you try using something like a paper drill - basically a razor-sharp steel rule die, but it spins in a drill press. I'm not holding my breath for sucess on that method either. Freezing to get the foam stiffer is unlikely to work, you will likely shatter the weak foam substrate before affecting the fabric layer much.
RE: Best way to cut ePTFE sheet laminated to a polyester/polyethylene backer
Regards
Pat
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