Shaving a beard with the resulting in loss of cutting ability of the blade is mainly due to corrosion not wear.
The reason that WC2 isn’t good from some materials is that loosely consolidated small abrasive particles can rapidly remove the binder for the carbide.
Now back to cotton and wear.
The original machines handling cotton had very slow filament speeds and all the materials were plain steels or cast iron. As the speed of the threadline increased next came the hardenable steel and the ability to flame hardened cast iron. The next step in the progression was that someone realized that if the relative speed of the threadline vs guide could be decreased by the use of roller guides, spinning rings with guides, etc. These were used first where there was a relative high angle of attack of the threadline vs guide or change in direction of the threadline. These rolls were made from various materials, some of which were CI, Case Hardened steel, even basalt.
The evolution of a particular guide first used in cotton mills called a “balloon guide” started out as plain CS progressed to hardenable steel, then to case hardened, then to carburized and then to case hardened and carburized, then to 1095 CS which in turn was case hardened and carburized. With the introduction of hard chrome plating all steel textile guides were immediate candidates for plating.
With the advent of Nylon the guide problem became more acute. Unadorned Nylon fiber causes extreme wear on anything it crosses or touches. This problem was attacked by the use of the hard chrome plate, the used of ceramics mainly “AlSiMag”for all pin small pin (convergence) guides, as the process for improved larger and larger guides were made from ceramics. Next came the thermal sprays including the CrO, “Polymet”. Thermal spray also allowed the roll to be made from steel which in turn allowed another speed increase and a repeat of the wear problem. Today we have synthetic sapphire and diamond coating. To add to discussion of static electricity nylon fiber under the right conditions will become a VanDeGraaff generator.
Back to cotton, if the threadline speed is below a certain threshold it will not wear guides to any extent. But as stated above as the speed increases the contact stresses increase to a point where the application of a finish or lubricant will decrease or prevent wear on the same guide. Finishes were usually made behind closed doors and were proprietary information of the highest order. Finishes for cotton soon had became generic and available off the shelf. The finishes again went underground when they started treating the cotton fiber to enhance it’s properties. Some of these properties allowed an increase in speed of the threadline and the contest to combat wear of guides began anew.
These finishes presented other problems as some were corrosive to certain materials until dry. Some contained waxes, fats, and oils which each in it’s own way affected the choice of guide materials.
The wear of a steel guide is affected by the threadline material, guide material , cleanliness of thread line, speed of the threadline, contact pressure on the guide, whether it is lubricated or not. All of these are common to wear problems.
If the above wasn’t windy enough this will be.
I have in my hand an extremely fine, several thousandth’s, Cu wire plated with diamonds. This is analogous to the “Angel Hair” of storied fame. The diamond particles are so small that the wire feels smooth but will cut just about anything going. The secret in cutting with this wire is that it has to move to cut without wearing out. If you rotate the part the wire tends to wear.
Just the opposite.
In another wear situation we had a 2" dia shaft made from “Vasco Jet 1000" hardened to 60 RHc rotating at less than 100 RPM @ 600°F we had an insulator/mechanic wrapped a single strand of 1/16" SS tie wire around the shaft. The initial load on the wire was in the order of several pounds tension, but would have went to essenitally nothing quickly. After about 100 days an unscheduled outage allowed the shaft and wire to be exposed. The SS wire had cut a 5/16" deep by exactly 1/16" wide, using the wire as a feeler gauge, groove in the shaft. The precision of this groove would be hard to duplicate. The most amazing part of the event was that it took an electron microscope to see any effect on the SS wire. The apparent abrasive media, none was seen embedded in the wire, was a small amount of the expanded calcium silicate dust from the insulation. This event occurred on another machine that ran for one year but wasn’t cut, only a very slight polish. The difference was temperature. The shaft temperature in this case was approximately 150°F instead of 600°F.
There has been a tremendous amount of work done on wear of guides both in the natural and synthetic fiber business. I know a considerable amount is still considered proprietary but enough has been published to keep from reinventing the wheel. Sometimes one has to take the Edisonian approach to get a starting point then start making incremental improvements until a problem becomes manageable. This is especially true with wear and the textile industry.
