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M4 x 0.7 pitch 40mm long nylon hex head screws

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#1 psi_chemie


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Posted 02 February 2013 - 09:45 AM

Got these to use in my XT4.5 dob secondary. I'm evaluating now but so far they work better than the metal screws and polyethylene washer. The question is over time will the plastic threads be deformed by the metal receiving threads.

Anyways I got 100 of these, if anyone needs a few and doesn't want to pay the $15 for 100 I will send out a few here or there..

#2 davidpitre



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Posted 02 February 2013 - 02:33 PM

The question is over time will the plastic threads be deformed by the metal receiving threads.

Probably a matter of the amount of torque used on them. Secondary screws are often tightened with quite a bit of force. This might deform the threads over time, but like you said, you have 100 of them, so no big deal.

#3 Geo.



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Posted 03 February 2013 - 11:29 AM

"NYLON 6/6 POLYAMIDE: General-purpose nylon 6/6 has good toughness, tensile strength, and resistance to creep, particularly in the high temperature range. Nylon has excellent wear properties, low coefficient of friction, and exceptional chemical resistance particularly to aromatic hydrocarbons, greases, and oils. Nylon is a hygroscopic material. Moisture acts as a plasticizer reducing the tensile strength, stuffiness, and increasing elongation, impact strength , and energy absorbing characteristics. Outdoor weathering can be improved by the addition of carbon black. Nylon will perform well in long range service in most applications at temperatures as high as 185° F (85° C). Nylon is a translucent off white color." http://rgafasteners-...n_test_data.pdf

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