Thread: Silicon Carbide (SiC) grits anyone?

Good one FF.

The coarse stuff is good for flattening coarse whetstones like the Sigma or Shapton 120s. For the Sigma Power Select II #240 I'm looking to use #60 grains; the coarsest is too harsh and the #90 in the kit not aggressive enough.

It appears from Stu that in Japan using SiC grains on a flat steel plate is the normal way of reconditioning a whetstone. I've been using plate glass which has held up well over 3 sessions on the Shapton #120.

I've had good results using #90 grains and above on overhead project transparency sheets on a granite reference slab for lapping the sole of a Stanley #3.

In short, a supply of these grains gives you the core of the Lee Valley lapping kit.

Actually the core and 80% more Ern. LV go 90-600 and skip 120. LV price per 100g (avge) is $8.60 per 100g, plus another $3.50 per 100g for post. Makes the price here of $1.75 per 100g delivered look pretty good.

HEY! Wait a minute! This is Straya! Shouldn't the price be the usual $20 per 100g, following the usual double it and some for measure? As Basil Fawlty said (with curled fingers and upwardly groping hands) "For the first time in my life, I'm ahead!"

Some may say that 1200 is unnecessary, and it probably largely is, but hey, while your at it, do it if you can.

You don't need all the grits; just the 120 and 240. (And the smallest amount you can buy).

Some 120 and some 240 is enough for everything I've done, from flattening the super-course Sigma 120, the Sigma 400, the King 1000 and 6000, lapping chisels and irons, and flattening planes.

The grit breaks down into smaller, finer particles quite quickly.

Thanks for sharing that experience Eddie.

I've been using Stu's #36 (breaks down quickly on the Shapton #120) and the others were LV (impression was not so quickly); has left me wondering about the quality of Gemcut's. Added: not that it matters that much since this game is not a scarcity one.

And KERRUMBS, my earlier post was #11000 !!!

How fine is that? (boom tish) )