3M Scary Sharp Sheets

[TheSandpaperMan]

Just arrived! #3M Microfinishing Lapping Film PSA (adhesive-backed) sheets. #These sheets are used for the "Scary Sharp" sharpening technique. #
Four sheet variety pack contains 1 each of 15, 5, 1, 0.3 micron. #
Sheet size is 215 x 280 mm. #
If you are trying to achieve the sharpest edge possible, these sheets are for you.
3M Microfinishing Lapping Film PSA (Adhesive Backed) - The Sandpaper Man (http://www.thesandpaperman.com.au/3m-microfinishing-lapping-film_psa-adhesive-backed.html)

[rsser]

:2tsup:

[FenceFurniture]

Just did a quick calc to convert to GRIT size using:

GRIT = 25.4 * 1000 / MICRON

That means these sheets are 1693, 5080, 25400 and 84666 grits
or (rounded):
1700
5000
25000
85000

Bloody Hell, that's fine!
Brett.

[rsser]

In ceramic waterstone terms (JIS) the first two particle sizes are no big deal. 15 micron is about #1000; 5 micron is about #4000.

I got some of this stuff from the US a while back when no one local had it. Good stuff. Micron graded; polyester film. My 15 and 5 are SiC; the 0.5 is chromium oxide.

3M also make it in Alox which would be a better option for hard steels; nothing here in Aus and v. difficult to find in retail quantities from US online shops.

[FenceFurniture]

On Sandpaper Man site it shows the first two as SiC and the 1 and 0.3 micron as AlOx.

BTW Ern, have you used Micromesh - if so, any good for wood or is it just for plastics, metals etc? I'm looking for something to cover 1000 and 2000 grit for final finish before shellac and/or wax. Wet & dry does a great job but goes "blunt" in a flash and at $2.50 per sheet..... It also sometimes leaves grey residue in the grain which is difficult/impossible to rub out with a cloth.

Regards, Brett

[rsser]

Thanks for that info Brett. 3M are sposed to make the alox 'microfinishing' film down to 100 microns which would be ideal for lapping.

But no, haven't used Micromesh. Have used Norton A275 to #1500 and it works OK.

What W&D brand are you using? Some brands have a poor bond.

Another option for you might be ubeaut EEE ... ?

[FenceFurniture]

Morning Ern, KMCA and Hermes. I've been getting the KMCA from the local Home Hardware (the whole packet of 25 sheets scans as a single sheet so I can't complain eh?), and the 2000 Hermes comes from from Carbatec. Seems to be the KMCA that leaves the difficult residue.

Just had a read about EEE and I think you may well be right. I've used the traditional wax and that's wonderful stuff, but must explore some other Ubeaut products.

Regards, Brett

[rsser]

Yes, KMCA is all that the local Bunnnings stock and it's not worth the paper it's printed on, even at your bargain rate ;-} See if you can find some Norton stock.

Agree, Trad Wax is good stuff and easy to use. For English Oak and Elm and other open-pored timbers the ubeaut Shithot Waxstik is worth a try. I've had some great results with it.

I don't use EEE much as my preferred finish is oil on darker timbers and sanding sealer and wax on lighter ones, so I really can't give you good user feedback but it seems many turners are impressed by it.

[FenceFurniture]

Thanks Ern, I'll try all of that (esp Norton).

[rsser]

Happy to share Brett.

My coarse KMCA sheets lose their grit rapidly with hand sanding of bowls on the lathe; the blue paper soon appears. Bunnings swapped from Norton to that junk and I didn't notice til at the lathe.