3M Microfinishing Film for tool sharpening

I bought this stuff from Tools for Working Wood a couple of months ago and have been using it since:

http://www.toolsforworkingwood.com/store/dept/THS/item/ST-MAF.XX/3M_Micro_Abrasive_Film__for_Scary_Sharpening_-_PSA

This finishing film from 3M is used in place of sandpaper for Scary Sharp. The grit of these are measured in microns. Tools for Working Wood has an article that gives a rough equivalency to the water stone grits. I.e. 1 micron is equivalent to a 1,000 grit stone. Please see: http://www.toolsforworkingwood.com/store/more/lappingfilm.html

I really like this stuff for scary sharp. For one thing, you can put a very fine edge on a tool with this stuff. Though I suspect going down to 0.3 microns may be overkill (I do it anyway). It lasts longer than regular wet or dry sandpaper. The adhesive is also reusable. Spray some water onto your sharpening surface before putting down the film. It will stick nicely and you’ll be able to remove it later. I think I’ve gotten the adhesive to last for 4 or 5 stickings and pulling up before it wears out.

The film is also fairly stiff for something so delicate, which is helpful. It stays in place and doesn’t flex. You can put it back onto the backing it came on to peel it off for next time.

From my experience I think it does cut faster than regular silicon carbide sandpaper, though not enormously so. It does seem to take less strokes on this stuff.

It does last a fairly long time, Longer than standard sandpaper. Eventually it will clog with metal particles and have to be discarded.

As I said, I really like this stuff. It isn’t perfect though. It can tear fairly easily, especially on the lower 3 grits. Sharpening only by pulling the tool (not the usual forward and backward pattern) helps. It also is much too delicate for power sharpening. I put some on the glass wheel of my Work Sharp 3000. The film abraded away to the glass in a matter of seconds. I suspect part of the reason for that is that I was using it dry. It’s really meant to have a lubricant. In other words, you must use it wet.

If you use scary sharp I think it’s worth picking up on one sheet assortments and trying it out.