One of the debates amongst our leadership and design team of late has been about replacing traditional elevator bearings with CNC machined delrin blocks to be used as linear slides. On last year’s elevator we used the traditional bearing approach, which worked well and never failed us all season, but was a huge time suck of machining and assembly resources. The delrin blocks on the other hand require only one setup on the mill and two screws to mount. Additionally, this would save us about 2.5 pounds of weight (which would have saved us a fair number of cheese holes at SFR).
All of that seems very attractive, but I am concerned about the reliability and longevity of this approach. I am afraid that overtime, the elevator may bind up and become less efficient. I think that we may see galling of the aluminum elevator members by the delrin sliders. Does anyone have prior experience?
One of our mentors had a case in which delrin butter pump rotors badly galled the stainless steel pump housing in which they rotated. You would think the plastic would lose and and the metal would win, but the reality was the opposite. As stainless steel wear particles embedded in the plastic, the wear couple essentially became stainless-on-stainless, and that wear couple is notoriously bad. It was sort of a runaway process. Aluminum-on-aluminum is also notoriously bad as a wear couple, hence my concern.
I did some googling, which suggests hard-anodized aluminum would work. However, if that route could be avoided, that would be fantastic.