Which is more rigid - PVC or Nylon rod?

[mikediamond]

Hello,

I want a threaded plastic rod that doesn't bend (preferably 3/4 diameter and 2 ft. length).

Which material is more rigid: PVC or nylon

What other material would you suggest?

 

[CoryPad]

Both PVC and nylon are available in thousands of grades with wide variation in properties. Based upon your simple question, either one could be made to work for you. Perhaps there are other requirements - must be able to withstand an impact force, must withstand a certain temperature, etc. These other requirements likely would move you into one material or the other.

From a mechanics standpoint, a beam in bending will be stiffest if composed of a material with the highest possible elastic modulus. Both PVC and nylons (without reinforcements) are available with moduli around 3 GPa. If the section shape is free, then the lightest (and cheapest) and stiffest beam is derived from a material with the highest ratio of elastic modulus to mass density. Since PVC is ~ 10% to 20% higher in mass density, it will be worse than nylon.



Regards,

Cory

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[patprimmer]

Like Cory said.

Your question is just to vague.

http://www.matweb.com

http://www.rtpcompany.com

both have very good data bases on plastics raw materials data.

On overall balance of properties normally required in constant high load applications, the materials of choice often end up being Glass filled nylon 6.6, Acetal, or Glass Filled PET.

Chemical exposure, UV light exposure, impact loads, cyclic loads and temperature range all have a significant effect on the choice.

Regards

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