Here at the company we've been working on a new product, and it will more than a few times a day and with a considerable force, slide on a plastic surface, being itself, another plastic body, roughly the same material, on will be injected to a mould and the other extruded, thats the main difference.

As we design, we thought of a friction problem due to the drag forces and the parts being in constant physical contact and one sliding on top of the other.

We thought we could reduce this problem by adding tiny spheric fixed protuberances that would reduce the contact area, this was 3D printed and tested and actually works, but we are worried that it will wear out soon due to extensive use. What other "mechanical tricks" are there to reduce friction between two surfaces?

Thank you for your answers :)

  • $\begingroup$ have you tried lubrication? Or magnets? $\endgroup$
    – Jim
    Jun 3 '14 at 14:01
  • $\begingroup$ we were thinking mostly of ideas that could be built on the material itself since we will be producing the products but not assembling them, so we would like to make sure we could solve the friction problem for both careful installers that would put some form of lubrication and not so careful installers that wouldnt care about that, because in the end of the day it is our name on the line, not the installer's. What do you mean by magnets? to keep one of the bodies suspended? I don't think that is feasible as we would spend more in magnets than the rest of the system xD nice idea anyway $\endgroup$ Jun 3 '14 at 14:35
  • $\begingroup$ Have you tough of hydro-static bearing? $\endgroup$
    – Foad
    Nov 2 '17 at 15:30

This sort of structured surface for friction reduction is an area of current research in phyiscs/engineering so its good to hear someone is actually using it and they work. Generally these surface are designed with indentations rather than protusions, more like a golf ball surface, precisely to reduce wear. Similarly changing the size/shape of the features will have a strong effect.

A more conventional approach would be to use some sort of lubricant between the surfaces such as oil or water to reduce friction, but I guess there may be reasons why you're not doing that anyway.

If you want something more exotic, anything that reduces the apparent load should help. Think repelling magnets or firing air through holes in one surface. Unfortunately I expect these more "cool" ideas are unlikely to very useful in practice.

  • $\begingroup$ So you think indentations would be better to reduce friction? right now we have 8 protusions about 1mm thick and 2mm in diameter in a surface of about 20cm2, would texturing the whole surface with these golf ball like indentations help with this problem? i dont think filling the surface with protusions would help, as that wouldnt reduce the contact surface as much as it does right now $\endgroup$ Jun 3 '14 at 14:41

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