kkrace wrote:
With the paint you might have to put it on fairly thick and then after it cures machine it down to fit? I don't have much experience with the 2 part epoxy paint so I'm just pulling this out of my ass.
That is what I did. Not because I was scared about curing but it was just easier to paint plenty and sand them in the lathe. The paint was for sure dry and hard at that time and sanding produce power with nothing sticking to the sand paper.
Knurling is very uncontrolledly so yeah it would have to be spun and sanded to size which would take the shaper edges off...I sand most everything I've been asked to knurl over the years so tools don't cut your hands and shafts press in without gouging as it goes...and that is my fear here. raising the surface 1 thou is a very light knurl which means that (after its smoothed) there might be 5-10% of the surface area contacting the block...there shouldn't be much force there but it scares me a bit that it will beat itself into the walls of the block over time.
You are the second person to suggest a piston coating material....it probably would work and will be on the to-try list once I look at a few easier to do options.
The graphite spray is here so I need to spray some on something and see what it does.....that and get all the liners out and cleaned up but other things continue to interfere. Yesterday my son's newish mountain bike got a flat, easy enough to pop apart but I have no way to put air into whatever the heck valve is on it so its sitting on the bench waiting a trip to the bike store today....which I'm told is near a nice kitchen cabinet store to look for something for the basement wet bar.