Norton India stone review w/ pics

[HeavyHanded]

My new Norton India stone and some observations.

Recently purchased a Norton India stone - the only AlumOx combination stones I owned were all cheapos that would shed grit and constantly need to be brushed/wiped off to keep the chunks from ruining my edge. Despite his I get some pretty good edges from them and decided to spend the 20.00 for the oft recommended India stone. I sharpened two knives on it - one per side to see what the edges would look like. Prior to any use I lapped the fine side with 220 grit SiC lapping compound and the coarse side with 120 grit compound - also rounded the corner off one edge on both sides so I can do recurve profiles. The coarse knife is a BK11 using 1095 CroVan and the fine knife is a hand- converted convexed TOPS C.A.T.




I used dish soap and water for lubricant. Stropped the coarse edge on 220SiC followed by a few swipes on black emery compound, the fine edge was stropped on black emery followed by a few swipes on Flexcut Gold.

Pics range from 160 to 640 to 1600

The coarse edge can just crosscut newspaper with a few hitches, and can easily cut with the grain. Will shave armhair but not facial stubble. It could just cut pushcut a pierced papertowel (per the Ankerson challenge - now one of my favorite "quick" edge tests).








The fine edge can crosscut phonebook paper with hardly a whisper, can just treetop leghair, and easily shave armhair and facial stubble. Would easily pushcut a pierced papertowel.









Without espousing coarse or fine, its easy to see how these edges are going to cut differently and why some edge strategies are much better than others depending upon whats to be cut. The notion that a coarse edge equals a dull edge just doesn't hold up.

Overall I really like the edges I was able to get from this stone - I have to agree with so many forumites who rate this as the "one" stone if they could only have one. Neither side sheds grit, in fact based on my efforts to lap this stone I'd have to rate it as one tough cookie. Dishing or loose grit will not be an issue. As with my other AlumOx stones, it is a bit tougher to remove the burr compared to diamonds or waterstones, but it has advantages over both - it can be shaped to sharpen hawkbills and recurves, and it requires no soaking or repeated lapping to keep it flat. I'd recommend this as a good buy for anyone starting out, or anyone looking to get a combination stone for their collection.

As a side thought, its entirely possible that one could further lap these sides down to get an even more refined edge - I was able to do so with a cheap stone lapped with a coarse and fine diamond stone respectively and the edge was clearly more refined. Considering the toughness of the Norton India, I suspect such a lapping would produce long-lasting changes to the stones character - I might do just this and make a follow-up post.

[big wes]

I have the same stone and I love it! It puts a nice edge on my knives in short order with very little effort. I do use oil for a lubricant and have no complaints. The best part is, the Norton stones aren't that expensive. everyone should own one IMHO.

[HeavyHanded]

As an added note on scale and the pics, I compared some toner particles to red blood cells and "verified" the scale that I determined mathematically. In the 640x images a single blood cell (6-7 microns) will be approx 3mm across, At 1600 that works out to just over 7mm. As soon as I can come up with a scientifically accurate method of including a scale reference I will, for now its approximate values.

[David Martin]

I agree and have touted their economy on this forum for years. They will sharpen any steel, wearing little while giving a nice edge and with only two grits. Its certainly a personal choice should one desire more grits but I can easily live with the two in this stone. They offer good quality. Thanks for the nice photos. DM

[knarfeng]

Those are great pics.
I have had a stone like that for many years. I still use it on occasion.

[Ankerson]

Great review.

I have the Norton C, M and Fine India stones and Med and Fine Sil Carbide Stones, all 8" - 3" stones.

[Lagrangian]

As an added note on scale and the pics, I compared some toner particles to red blood cells and "verified" the scale that I determined mathematically. In the 640x images a single blood cell (6-7 microns) will be approx 3mm across, At 1600 that works out to just over 7mm. As soon as I can come up with a scientifically accurate method of including a scale reference I will, for now its approximate values.

Hi HeavyHanded,

You mention a length of 7mm on your screen. But people are viewing your images on different sized monitors; some of us are viewing your images on 18-inch computer monitors, while others are using 30-inch monitors. On these different sized monitors, 7mm means different things, since they have different dpi.

Maybe you could just mention the width of your field-of-view in mm (or microns)? Or maybe how many microns per pixel?

Sincerely,
--Lagrangian

P. S. I had some additional thoughts on how to calibrate microscope images, and Ken Schwartz had a suggestion too. I posted this thread about it:
http://www.bladeforums.com/forums/sh...a-Length-Scale

[HeavyHanded]

Right you are - next time (or I'll add a response with better scale info to this thread) I'll include field of view in microns or relink to the same pics with a scale included. Your ideas in the other post re use of foil are good too - I'll have to mic some because foil comes in different thicknesses as well, but I have been imaging cut ends of paper (actually using it for the reasons it was purchased) and it can't be any tougher to use foil. Don't believe that will work for 1600x but I'll give it a try - can press it within a notepad or similar giving the oil something to ride on.

HH

[Whitedog]

That is a very good stone you have there. Mine is going on 30 yrs now and does a great job. No dished out spots at all.

[David Martin]

White, Thats great. I was hoping someone could come on and post that margin of longevity using this stone with good results. DM

[sitflyer]

been using a 8X3 fine for 20 years...hair popping sharp with all my knives. I use DMT's for the re-profiles, then always finish on the Norton. I will only use oil on the alum-oxide
and finish by making very light "slicing strokes" on the stone. I used this stone on my chefs knives when I was cooking...it's seen a lot of use and is still flat.

[David Martin]

We now have the 20, 25 and 30yr. usage with this stone covered. DM

[THG]

Hair-popping on these stones? Really? I thought it's been said that this stone and the SiC stones are comparable to about 320 grit on the fine side.

[HeavyHanded]

Hair-popping on these stones? Really? I thought it's been said that this stone and the SiC stones are comparable to about 320 grit on the fine side.

320 grit on the fine side? I don't think so. Not that one cannot pop hairs at 320grit, but these stones are a bit more refined than that. I have a cheap combination Norton SiC stone, and the India - both are quite a bit finer than 320 - closer to 600 or 700 from the SiC and off the India (AlumOx) I'd say its more refined than a DMT EF which certainly produces a hair-popping edge (pictured below at 640x - compare to the middle pic from the fine India just beneath). Difficult to say exactly what grit they really are, as they can be lapped to produce different characteristics.

[Ankerson]

320 grit on the fine side? I don't think so. Not that one cannot pop hairs at 320grit, but these stones are a bit more refined than that. I have a cheap combination Norton SiC stone, and the India - both are quite a bit finer than 320 - closer to 600 or 700 from the SiC and off the India (AlumOx) I'd say its more refined than a DMT EF which certainly produces a hair-popping edge (pictured below at 640x - compare to the middle pic from the fine India just beneath). Difficult to say exactly what grit they really are, as they can be lapped to produce different characteristics.

Yeah the Norton Fine SIC is finer than people would think once they break in good (One or 2 blades).

[wintermute]

How well do these stones sharpen the harder super steels, not that I'm one for anything too exotic, but just curious. I'm all about cheap and easy and I'm not interested in fancy or expensive sharpening systems.

[HeavyHanded]

They're both over a 9 on the Mohs scale with the SiC just a bit harder than the AlumOx - they should handle about anything but ceramic.

[Ankerson]

How well do these stones sharpen the harder super steels, not that I'm one for anything too exotic, but just curious. I'm all about cheap and easy and I'm not interested in fancy or expensive sharpening systems.

SIC will eat any steel, even 10V without much trouble so the more normal steels will be cake.

These days SIC is all that I use because of the very high wear resistant steels I like to use, I am talking about S90V, S110V and K294 (10V).

[tiguy7]

SiC was developed in part to sharpen Tungsten carbide tool bits (72HRC). I have a calibrated microscope slide that has graduations in 1/100 mm. I would be happy to lend it out to a responsible knife edge scientist for calibrating his/her equipment.

[coyote711]

I agree and have touted their economy on this forum for years. They will sharpen any steel, wearing little while giving a nice edge and with only two grits. Its certainly a personal choice should one desire more grits but I can easily live with the two in this stone. They offer good quality. Thanks for the nice photos. DM

I'll back ya up there, David!

Looking for my first stone a couple years ago, I was fortunate to develop a friendship with David, who recommended the Norton India Combo stone. I couldn't have received better advice - it's a great stone!

Since then I've acquired a limited number of other stones ..... Norton SiC Combo, DMT's, Arkansas ..... but the India is by far the most used. And if I was ever forced to choose just one stone, to the exclusion of all others, the India Combo would be the one I'd pick. (Norton SiC would be 2nd).