Howdy,
I was perplexed because the resulting edge seemed so much
better when I sharpened my leather working round knives on
2000 grit paper as compared with a 7000 grit waterstone.
But then I realized that I was comparing two different
systems of grit measurement.
Do you know of some conversion system? That is, what paper
grit size might be equivalent to a 7000 grit Japanese
waterstone?
Sincere thanks,
--
Kenneth
If you email... Please remove the "SPAMLESS."
On Mon, 11 Feb 2008 16:35:56 GMT, "George" <[email protected]>
wrote:
>
>"Kenneth" <[email protected]> wrote in message
>news:[email protected]...
>>
>> Howdy,
>>
>> I was perplexed because the resulting edge seemed so much
>> better when I sharpened my leather working round knives on
>> 2000 grit paper as compared with a 7000 grit waterstone.
>>
>> But then I realized that I was comparing two different
>> systems of grit measurement.
>>
>> Do you know of some conversion system? That is, what paper
>> grit size might be equivalent to a 7000 grit Japanese
>> waterstone?
>>
>
>Among other places available with a search for grit comparisons, this is a
>good one
>http://www.marine.nortonabrasives.com/Media/Documents/S0000000000000001074/Coated%20Abrasive%20Basics.pdf
>because you can print it for your notebook or wall.
Hi George,
I thank you for that suggestion, and it is a useful
resource, but (unless I am misinterpreting something) it
does not go nearly fine enough for my needs.
All the best,
--
Kenneth
If you email... Please remove the "SPAMLESS."
On Mon, 11 Feb 2008 11:26:18 -0500, Kenneth
<[email protected]> wrote:
>
>Howdy,
>
>I was perplexed because the resulting edge seemed so much
>better when I sharpened my leather working round knives on
>2000 grit paper as compared with a 7000 grit waterstone.
>
>But then I realized that I was comparing two different
>systems of grit measurement.
>
>Do you know of some conversion system? That is, what paper
>grit size might be equivalent to a 7000 grit Japanese
>waterstone?
>
>Sincere thanks,
Interestingly, I have been building an Excel spreadsheet with just
that information. Most sources don't go smaller than 5 microns, so I
took an existing table and added the smaller data from various
sources. It may be useful to others. Note that there is some variation
in different sources between what "CAMI" vs. "FEPA" vs. "Microns" and
"Japanese" actually measures to.
Since rec.woodworking doesn't want binary attachments, I've attached a
"CSV" file (means comma separated value, I think) that can be loaded
into just about any spreadsheet program out there.
Since I don't know that rec.woodworking even wants that, I've also
pasted the CSV information below. You could copy that and paste it
into Notepad (or other plain text editor) and save it to a file, then
load that file into your spreadsheet program.
Good luck
,CAMI Grit designation,ISO/FEPA Grit designation,Japanese,Average
particle diameter (µm),Examples
Extra Coarse (Very fast removal of material),,P12,,1815,
,,P16,,1324,
,,P20,,1000,
,,P24,,764,
,24,,,708,
,,P30,,642,
,30,,,632,
,36,,,530,
,,P36,,538,
Coarse (Rapid removal of material),40,P40,,425,
,50,,,348,
,,P50,,336,
Medium (sanding bare wood in preparation for finishing),60,,,265,
,,P60,,269,
,,P80,,201,
,80,,,190,
Fine (sanding bare wood in preparation for finishing),,P100,,162,
,100,,,140,Coarse Crystolon
,,P120,,125,
,120,,,115,
Very Fine (final sanding of bare wood),,P150,,100,
,150,,,92,Medium Crystolon
,180,P180,,82,
,220,P220,,68,
Very Fine (sanding finishes between coats),,P240,,58.5,
,240,,,53,Fine Crystolon
,,P280,,52.2,
,,P320,,46.2,
,,P360,,40.5,40 micron SiC paper
Extra fine,320,,,36,
,,P400,,35,Extra fine scotch brite pad
,,P500,600,30.2,
,360,,,28,Washita oil stone
,,P600,,25.8,
Super fine (final sanding of finishes),400,,,23,
,,P800,,21.8,
,500,,,20,Soft Arkansas stone
,,P1000,,18.3,
,600,,,16,
,,P1200,,15.3,"15 Micron belt, 15 micron SiC paper"
Ultra fine (final sanding of finishes),800,P1500,2000,12.6,"Hard white
Arkansas, extra fine diamond, and medium ceramic"
,1000,P2000,4000,10.3,
,,P2500,,8.4,"Hard black Arkansas, 9 micron belt"
,1200+,P4000,,5,5 micron SiC paper
,1500,P6000,6000,3,"Extra fine white Ceramic, green chrome rouge, 3
Micron belt."
,,,8000,2 or 3,Japanese Water stone
,2000,,15000,0.9,Japanese Water stone
,12000,,30000,0.5,"Chromium oxide polishing compound, 0.5 micron
Chromium oxide paper, Shapton 30000 stone, diamond paste "
Kenneth wrote:
> Howdy,
>
> I was perplexed because the resulting edge seemed so much
> better when I sharpened my leather working round knives on
> 2000 grit paper as compared with a 7000 grit waterstone.
>
> But then I realized that I was comparing two different
> systems of grit measurement.
What kind of sandpaper? 2000 grit FEPA is roughly 10 microns, while
2000 grit CAMI is around 1 micron but isn't as uniform (can contain
larger particles that will leave stray scratches).
According to
http://www.leevalley.com/wood/page.aspx?c=1&p=46224&cat=1,43072 an 8000
grit waterstone should be around 1 micron.
Are you sure your waterstone was flat and that you polished to the same
degree using both techniques?
Chris
On Feb 11, 9:13=A0pm, Zz Yzx <[email protected]> wrote:
> >I was perplexed because the resulting edge seemed so much
> >better when I sharpened my leather working round knives on
> >2000 grit paper as compared with a 7000 grit waterstone.
>
> >But then I realized that I was comparing two different
> >systems of grit measurement.
>
> >Do you know of some conversion system? That is, what paper
> >grit size might be equivalent to a 7000 grit Japanese
> >waterstone?
>
> >Sincere thanks,
>
> I once spent a fair amount of effort to resolve this exact issue. =A0I
> compiled a spreadsheet, based on several sources, regarding the
> relative grit-size of the various grading systems. =A0I'll post hte
> spreadhseets over on teh binaries group, with a bit of detail.
>
Excellent! Very much appreciated, sir.
*tips hat*
r
>I was perplexed because the resulting edge seemed so much
>better when I sharpened my leather working round knives on
>2000 grit paper as compared with a 7000 grit waterstone.
>
>But then I realized that I was comparing two different
>systems of grit measurement.
>
>Do you know of some conversion system? That is, what paper
>grit size might be equivalent to a 7000 grit Japanese
>waterstone?
>
>Sincere thanks,
I once spent a fair amount of effort to resolve this exact issue. I
compiled a spreadsheet, based on several sources, regarding the
relative grit-size of the various grading systems. I'll post hte
spreadhseets over on teh binaries group, with a bit of detail.
-Zz
"Kenneth" <[email protected]> wrote in message
news:[email protected]...
>
> Howdy,
>
> I was perplexed because the resulting edge seemed so much
> better when I sharpened my leather working round knives on
> 2000 grit paper as compared with a 7000 grit waterstone.
>
> But then I realized that I was comparing two different
> systems of grit measurement.
>
> Do you know of some conversion system? That is, what paper
> grit size might be equivalent to a 7000 grit Japanese
> waterstone?
>
Among other places available with a search for grit comparisons, this is a
good one
http://www.marine.nortonabrasives.com/Media/Documents/S0000000000000001074/Coated%20Abrasive%20Basics.pdf
because you can print it for your notebook or wall.
You can post binaries at alt.binaries.pictures.woodworking
and point to it in your replies here.
Art
"Jim Weisgram" wrote
>
[snip]
> Since rec.woodworking doesn't want binary attachments, I've attached a
> "CSV" file (means comma separated value, I think) that can be loaded
> into just about any spreadsheet program out there.