Why Does This Lubricant Work So Well?
My guess is that we are forming long polymers of soap molecules joined end to end by glycerine molecules, i.e.. --> soap-glycerine-soap-glycerine-soap-glycerine……polymers. The remaining water and glycerine lie between these long polymer chains, lubricate them and allow them to slide relative to each other.
The icing on the cake is that the very high pressure under the BR rollers of ~100,000 psi aligns these polymer chains along the roller direction. So the chains are not tangled but free to slip and slide. And the chains are easy to break if they do get entangled because the glycerine-soap bond is a weak Van der Waals bond.
Molecular Composition of Lubricant:
The MOLECULAR composition of this lubricant is 63 molecules of water, 63 molecules of glycerine and 1 molecule of soap. That may sound like very little soap but it is not when you look into the fluid at a molecular level. The soap molecule is about 20 atoms long; consider a virtual box in the fluid 20 molecules Long by 5 molecules Wide by 5 molecules High. Looking into the end of the box along the roller direction, we find 4 soap molecules in just this small 5X5 cross section. So we really have a lot of soap.
Temperature Range of Lubricant:
’ve run this lubricant at temperatures as high as 80 °F and as low as 35 °F. I put the lubricant in our freezer and it does not freeze down to ~20° F.
High Pedal-Pressure Range of Lubricant:
I’ve searched Google for references to a lubricant like this. The only thing that I have found is passing references that say that high-pressure metal formers use glycerine-soap mixtures as their lubricants. Naturally, they keep this composition as a trade secret just as the oil/gas fracking industry keeps their fracking fluid compositions secret. The exact lubricant composition used by the metal formers is the only advantage they have over their competitors. Your seamless stainless steel kitchen sink as well as your seamless hot water tank are forged from one sheet of metal coated with a lubricant, that is forced by either high pressure or a male metal die into a female metal die. The yield of this process is highly dependent on the lubricant used. The metal must stretch by huge amounts without hanging up on the walls of the die and tearing.
We also have a high-pressure situation under our Delrin rollers so it is not surprising that a pseudo metal-former lubricant would work well for us too.
Application of Lubricants to Roller Tracks:
I apply the GWS to both the large roller track and the small roller track on the inner top surface with my index finger. A little dollop of lubricant is sufficient. With your finger, it is easy to tell when the hidden inner top surface is completely coated by how slippery the surface is without having to bend over and look.
I recently had to install two new inner rollers after a losing one on a long trip (more on this later; in short, it was my fault). The new rollers were relatively noisy compared to the old ones probably because their cylindrical edges were not worn in yet. Their bothersome noise induced me to rub lubricant on their tracks as well and that eliminated their noise too. The lubricant on the top surface stayed in place for my 40-mile trip.
Ive gone over 100 miles (160 km) with one application of this lubricant and it was still working well. In fact, an oddity about this lubricant is that it seems to get better with use. During one test, out of laziness one morning, I just added a few dabs of new lubricant to the old contaminated one on the track. It seem to work better than if I had rigorously scrubbed and washed away the old lubricant and started with new lubricant.
I’m seeing less Delrin wear particles and mostly aluminum flakes from the track. This may be caused by the fact that I sanded off 25-75 microns (2-3 mils) from the sides of my large Delrin roller from an ID of 20mm to 26mm to allow a space between the side wall and the roller and eliminated the drag caused by differential radial velocities scraping the side walls at different heights. Or it may have something to do with the new lubricant. If you have a good imagination, you might be able to see the aluminum flakes on the Delrin roller surface in the third photo. Also notice that the side walls are not being cleared of lubricant like the bottom track is because there is no roller-wall contact on the side walls.