Thread: Grit size?

Few days ago i found that my Japanese Sun King 1k stone had been cracked in two pieces. Shit happens, i've had it about 10 years or more, so maybe it just got tired for serving me after all these years.
I purchased new Norton 1k stone, and i noticed that it feels much coarser than Sun King, even after lapping it.
Now the question goes how is this possible?. I know that the grit size is the grit size, no matter who made the stone. The same goes with all my Japanese/Norton stones. Japanese 4k and 6k stones feel much finer than Norton 8k. What is the point i didn't get?

Grit size unfortunatly is not very uniform... Just close... So if you get 5 1k stones from 5 different manufacturers you will have 5 slightly different stones. At the lower ranges this is not a huge differentce but it can be once you hit the 10k range.

Also the type of grit used can be very different and act different. Some break down and get finer as you go, others remain intact and yet others are shapped different. You will notice a huge difference from a diamond cutter vs a garnet cutter.

Originally Posted by DwarvenChef

Grit size unfortunatly is not very uniform... Just close... So if you get 5 1k stones from 5 different manufacturers you will have 5 slightly different stones. At the lower ranges this is not a huge differentce but it can be once you hit the 10k range.

Also the type of grit used can be very different and act different. Some break down and get finer as you go, others remain intact and yet others are shapped different. You will notice a huge difference from a diamond cutter vs a garnet cutter.

This is how i think too. I just didn't understand how can the difference between these two 1k stones be that big. Now i bet that Norton must be much faster than Sun King. Making a bevel for razors, knives and tools with Japanese have been very slow process.

Yes King stones are slow cutters, I still use my 1200 King for a few uses but cutting ability is not one of them haha. It leaves a very nice smoked look on Iron, when sharpening my single bevel japanese kitchen knives

Sailor, if you go to post #38 in this thread here you'll find the latest version of a grit comparison PDF between USA and Japanese synthetics. I don't know how accurate it is but it may give some indication of the differences you feel.

BTW, I was speaking with the fellow in charge of honing at Japan Woodworker sometime back. In the course of the conversation he mentioned that he has glued many a broken stone with gorilla glue. I've never done it myself but it might be worth a try with your sun king 1k.

Originally Posted by DwarvenChef

Yes King stones are slow cutters, I still use my 1200 King for a few uses but cutting ability is not one of them haha. It leaves a very nice smoked look on Iron, when sharpening my single bevel japanese kitchen knives

I reckon they must vary considerably then - I'm very familiar with the King 1000/6000 combo and found the 1000 side much, much faster than a Norton 1000 I had. Bright finish, too.

Regards,
Neil

Yup, check out the grit conversion chart; IIRC JIS are finer than US grits. I find my Norton 1k to be a very aggressive cutter, which is a big part of why I love it so much.

Thank you gents for useful info and specially Jimmys link. After checking that grit chart i can now understand why bevel setting has taken so damn long, and why my 6k King feels finer than 8k Norton. Now as i have Norton 1k, things should speed up a little.

Trying to fix that cracked King stone as i've used it as great 'touch-up' stone for tool edges. We have no gorilla glue here in Finland, or at least i have never seen, but i think Loctite 454 should do the trick.

Originally Posted by Sailor

Few days ago i found that my Japanese Sun King 1k stone had been cracked in two pieces. Shit happens, i've had it about 10 years or more, so maybe it just got tired for serving me after all these years.
I purchased new Norton 1k stone, and i noticed that it feels much coarser than Sun King, even after lapping it.
Now the question goes how is this possible?. I know that the grit size is the grit size, no matter who made the stone. The same goes with all my Japanese/Norton stones. Japanese 4k and 6k stones feel much finer than Norton 8k. What is the point i didn't get?

There are multiple standards. i.e. The US and Japanese standards differ
by a lot. For others reading this, this is why some recommend hones from a
single vendors line.

Conversion Chart Abrasives - Grit Sizes

But you are apparently seeing this backward from my
expectations... The very fine hones are effectively
off the charts... The other component is the statistics
of the abrasive size. There is a Max size, an average
size, and more....

The other bit is the shape and composition of the abrasives
used as well as the binder used in making the hone. The
resin bonded hones feel softer to me.

http://straightrazorpalace.com/advan...tml#post432779

I always get confused by this...