Our treated rod bearings are not coated; coatings tend to add too much material and interfere with proper tolerances, causing more problems than they solve. The bearings we use in our kits have been treated with a process that not only makes the grain structure in the surface of the bearing smoother, but also aids in oil retention, providing more lubricity in this critical area of the S65 engine.
Incorporating T-lip wiper seals, radial shaft seals, o-rings or any other similar internal sealing system is not a problem for PolyLube Guide Rod Bearings. Polygon’s internal fabrication capabilities allow for easy and economical incorporation of ID features required to install common sealing systems.
One common fabrication detail seen on guide rod bearing applications deal with corner radiuses on internal and external grooves. Because Polygon uses a diamond wheel or groove tool to form the grooves we need to have at least a .015-.020" (0.38-0.51mm) corner radius. When threads are used there is usually clearance involved. When assembled with the mating part the bearing could shift to one side or the other impacting the location of the bearing surface in relation to the piston shaft. This could have a negative impact on wear.
Second, thermoplastic bearing materials are prone to cold flow. Under constant load many thermoplastic guide rod bearings will exhibit creep. This creep will result in slop in the bearing assembly and will negatively effect any precision the slide block is expected to maintain.