I think I’m in a spot that a lot of people are. I bought the 1500 grit stones and an extra set of blank glass platens. I also have the 4/2 and 1/0.5 emulsion strop pack.
I’m currently using 6,3, and 1 micron films; I went 3 to 1 instead of 3 to 1.5 because I’ve never had a problem with that progression when using 3m diamond films before and started with the 6 micron film because it’s the film used after the 1500 grit diamonds in the Pro Pack III kit.
However, I’m starting to wonder if it wouldn’t make more sense to switch to 9, 6, and 3 micron films since 3 micron films already give a nice polish. I figure that the strops could improve the finish and sharpness to a level I’d probably find indistinguishable from the 6,3,1 progression. Also, I would think that the 9 micron film might do a better job at cleaning up any errant scratches from a coarser grit that for some reason I might have missed. If a 2:1 micron ratio is a conservative progression to use, the 9 micron film should even be able to efficiently work scratches from the 600 grit stone; they aren’t the exact same kind of abrasive though so who knows.
Does anyone have any thoughts on this? Am I overthinking this?
400 / 600 / 800 / 1000 / 1500 / 6 mu dlf / 3 mu dlf / 1.5 mu dlf / 1.0 mu dlf
If the job demands it, I will then strop with 0.5 mu paste, then 0.25 mu paste.
With my kitchen knives, I will normally stop after the 3.0 mu film.
While inserting a 9-micron DLF step seems to make sense, in practice it doesn’t seem to be necessary. The step from 1500-grit diamond to 6-micron film seems to work very well. I suspect that the 9-micron film produces the same sort of scratch patterns as the 1500 grit. In any case, the 9-micron film seems to be a wasted step.
I would encourage you to read this thread from when the 1500 grit diamond stone was first released. It contains a discussion about which lapping films are the best to use after the 1500 grit and Clay posted some very informative microscope images to guide the discussion.
Thanks for the info guys. The photos in the thread are helpful. I don’t think I’ll be working the 9 micron films in my progression unless I feel the need to buy a whole new set of blank handles.
I thought you’d come to that conclusion after seeing the results up close. The progression from 1500# to the 6 micron diamond lapping film has been well vetted. Adding the 9 micron film would be unnecessary for the majority of use cases.