From: burnard@taligent.com (Dave Burnard)
Subject: Re: How to use waterstone?
Followup-To: rec.woodworking
Organization: Taligent, Inc.
Distribution: usa
Date: Mon, 11 Jan 1993 19:37:02 GMT

In article <1993Jan11.160541.28327@slcs.slb.com>,
weissborn@DFWVX1.DALLAS.SDS.SLB.COM wrote:
> >Waterstones with wooden bases (most polishing stones come this way) cannot be
> >left soaking.  Polishing stones do not need to be immersed before use - you
> >can just splash a little water on their surface.  A 'nagura" stone is
> >available to help in using the harder polishing stones.  This is a chalky
> >stone that is rubbed over the surface of the polishing stone and creates
> >a paste containing some of the abrasive from the waterstone.  Personally,
> >I haven't found that the nagura stone does much - I'm probably using it wrong.
> 
> I thought the nagura stone was used to flatten the polishing stones?
> 
> >  .... more stuff deleted....
> >
> 
> Anyone have a favorite supplier/mail-order source for these stones?  I see them
> advertised all over under varying brand-names and wonder if one brand is better
> than another.   Currently, I have a 1000/6000 combo stone.  I am looking for 
> an 800 grit to whip some old planes into shape.  Also, what is the net-wisdom 
> on going from 1000 to 6000?  Should I also get a 1200 or some other intermediate
> grade before going to the 6000?
> 
> Thanks for the feedback
> 
> 
I've had quite a bit of experience with Japanese Water stones, both natural
and man made. So here's my two cents:

Nagura Stones: Nagura stones are NOT used to flatten other stones, they are
used to enhance the sharpening characteristics of waterstones.  They are
actually very helpful, but your mileage will depend on the type of stone
you are using it with, as well as the hardness of the steel you are working
with. On inexpensive "Western" chisels (sears or stanley) the steel is
"relatively" soft and I find the nagura doesn't help much on any stone.
With the extremely hard steel found in Japanese chisels, and in some of the
finer western tools, using the nagura to create a bit of paste on the
waterstone can really help.  When sharpening, if the tool slips or chirps
across the stone, try a little nagura. Some natural polishing stones are
very hard, and really need the nagura.

Stone Selection: 1000/6000 is quite a jump if you are really going for a
razor edge. It will take a lot of polishing to get out the scratches left
by the 1000 grit stone. Unfortunately there aren't many types of stones in
between. The choices are: 1) use a 1200 instead, or 2) try a 4000 grit
polishing stone before going to the 6000, 3) use a 1500 as a middle stone
(Japan Woodworker - Woodline in Alameda, CA also sells one) or 4) Get
yourself a natural "Ocean Blue" middle stone which is equivalent to about
2000-2500 grit. Unfortunately "Ocean Blue" stones are "mined", not
manufactured and last I heard the underwater mine was closed or nearly so.
Last time I asked, Hida in Berkeley, CA still had a few. Many of the stones
left on the market now, are of low quality and tend to "disintegrate" into
smaller randomly shaped chunks. Ask about the quality if you find one.

I'm fortunate enough to have a blue stone, and it works extremely well. If
such a stone is either no longer available (likely) or too expensive (also
likely), then I think I'd opt for the 1500 as a middle stone. My current
stone collection includes 600,800,1200 (the workhorse), ocean blue, 6000
and several natural polishing stones. For a chisel or plane blade I usually
start on the 1200 unless there are big problems, then move to the blue
stone, and then finish up on the 6000, or one of the natural stones,
depending on the quality of the tool (no sense polishing a $3 chisel on a
$200 natural waterstone). I tend to use the nagura with the middle and
polishing stones, but sometimes I use with on the 1200 as well.

Don't forget to flatten your stones regularly, the "red" King brand
800-1200 stones wear especally fast. I prefer the Bester brand ceramic
stones (white or yellowish). I use a piece of 1/4" glass with a piece of
sandpaper on top, and just rub the stone on the sandpaper.

Good luck!

Dave