Sharpness question

[Tynyyn]

A fellow member in the Tools for sale section had recently put up a Norton stone with 6000 and 8000 grit for sale.  That got me thinking about sharpness.

I sharpen my irons to 1000 grit.  Would they perform better if I sharpened them to 6000 or 8000 grit or is that splitting hairs?  I've seen Japanese planes sharpened to 10000grit and the shaving was very thin, almost see-through.  Do our planes need to be that sharp or is that like purchasing a Cadillac when a Chevy would do?

[Strokes77]

This thread will derail quickly.

My advise is this, if you're happy with results, don't chase higher grits.

I stop at 1200 then strop, and love it. Others would call me a barbarian...

[Admiral]

This thread will derail quickly.

My advise is this, if you're happy with results, don't chase higher grits.

I stop at 1200 and love it. Others would call me a barbarian...

Agreed there will be many, many opinions, sometimes sharpening threads get a life of their own.

Personally, I go to two grey ones, followed by a red one; both from flea markets and I have no idea of what grit they are, then I strop with green compound, then I strop on a brown grocery bag on my jointer bed.  Works for me

[AHill]

You don't NEED another stone at a higher grit, but you will benefit from a higher grit honing.  A leather strop with the green honing compound (I like Lee Valley's the best) would get you a very sharp edge.  Your edge will last longer between sharpenings, and if you touch up the iron on the strop, you probably won't need to hit the stones as often.

Now, all that said, I don't know too many hand tool workers that stop at 1000 grit stone.  At a minimum, they'll strop.  If you get an 8000 grit stone, there's no need to strop (debatable).  (I still like a charged strop to touch up my chisels and plane blades during use, but I do hone to 8000 grit when sharpening.  I think anything beyond 8000 grit operates on the law of diminishing returns - the benefit of being REALLY sharp is outweighed by the time and effort to get there, and the benefit is fleeting at best.

These are my experiences.  There are many ways to get things to work for your work methods.

[JimReed@Tallahassee]

Like a lot of other things--it depends. What are you planning? Is it for fine finishing? Or jointing? Fine finishing would appreciate sharpness and jointing would  chew up that super sharp pretty fast. I sharpen most of my plane blades and finish with 400 or 800 AO paper. And I find that used paper works best. The 400 leaves a nice polish if it is worn a bit. But in my opinion, that 8000 stone is for sushi knives.

[Mike Sieweke]

If you're using a strop, then you're sharpening past 1000 (or 1200) grit.  Chromium oxide stropping paste is 0.5 microns, which is finer than CAMI 2000, FEPA F2000, or JIS 8000 grit.

Going to a finer stone might save you time stropping.  Paul Sellers says you only need to sharpen with 250 grit, but he does at least 30-40 passes on the strop with lots of pressure.  Which is more work - stropping 40 passes or taking 10 passes on an 8000 grit stone?

Do you need a finer stone?  No.  Lots of people did (and do) great work with coarser stones.  You could waste a lot of time going down this rabbit hole.  (If you like rabbit holes, google "Brent Beach sharpening" and "infill blade test".  Those guys tested blades sharpened with different grits.  Interesting stuff if you like geeking out instead of making things 
. )

[Timberwolf]

A fellow member in the Tools for sale section had recently put up a Norton stone with 6000 and 8000 grit for sale.  That got me thinking about sharpness.

I sharpen my irons to 1000 grit.  Would they perform better if I sharpened them to 6000 or 8000 grit or is that splitting hairs?  I've seen Japanese planes sharpened to 10000grit and the shaving was very thin, almost see-through.  Do our planes need to be that sharp or is that like purchasing a Cadillac when a Chevy would do?

..............

The answer to that IMO is..how much work do you like to do ???? ..The sharper they are to start with, the longer you will be pleased with how they are cutting, IOW, the longer they will stay sharp, providing you have good steel...I like a highly polished edge and you probably wont get that stopping at 1,000, unless you "power strop".....Power stropping on charged leather is similar to honing on an extremely fine stone. You can actually take a really dull edge and restore it to hair-popping sharp in a minute {or less}...You can power-strop on a charged leather wheel and create a sharp edge where there never was one. Think of a leather stropping wheel like it's an extremely fine sharpening stone moving at high speed against the steel. But it's a learning curve that many folks give up on before they master it. You can blunt the edge in a nano second with bad technique, and that's why lots of guys give up on it....They never took the time to master the technique..Practice alone does not make perfect..."perfect practice" makes perfect.

I use a leather wheel, muslin buff, or a slow-speed leather belt for stropping and have all three machines mounted on the same bench. "Sharp" means different things to different people..... Why not strive to be the best you can be ??..Don't settle for a Chevy when you can easily drive a Cadillac. That's all I have to say about that...

Signed,
Forrest Gump

[Arch_E]

Sharpening our tools is a necessity; but, the degree of sharpness sought is personal preference. What one is working (context) should also impact this discussion, i.e., figured wood, end grain, hard or soft woods, etc.

Several really reputable ww's have already given solid answers above. To those I perhaps add nothing of genuine value other than stressing that either we should have fun with our chosen path of sharpening (which is why I don't like sandpaper [though it works]) or we should achieve repeatable efficiency. IMO, that's it. Whether that's ending at 1k, 3k, 6k, 8k, 10k, 13k, or 30k, the only person it should matter to is the one pleased with process or proficiency. 

So, to elaborate just a little more: when I'm working straight predicable grain, finishing out at 3000 (plus a few pulls on a plain leather strop) is normally all I need. For end grain, I'll go all the way to 10k or 13k. Same for highly figured grain or difficult interlocking grains. Nevertheless, the edge I achieve off any of my 1k or 1.2k stones is really good, too; it's just that the blades appear to dull quicker in use (my experience). 

Of all the stones I've tried, I really liked the Norton 4k and 8k stones (though I esteem them as perhaps closer to 2800 and 6000 grit). The 4000 stone gives great feedback, hones very nicely, and does an excellent job in polishing--all the while not dishing or getting used up too quickly. It's an excellent stone. The Norton 8000 is, likewise, a solid user though giving less feedback and polishing (than other high grit stones). Again, I wouldn't hesitate to recommend either for regular sharpening. OTOH, if cost were the same, I'd recommend several other brands as a better bang for the buck.

[hbmcc]

I like my tools dull. Dull, Dull, D.U.L.L.. 

[Not really. Just my Stanley Stud Persuader.]

[Derek Cohen]

A fellow member in the Tools for sale section had recently put up a Norton stone with 6000 and 8000 grit for sale.  That got me thinking about sharpness.

I sharpen my irons to 1000 grit.  Would they perform better if I sharpened them to 6000 or 8000 grit or is that splitting hairs?  I've seen Japanese planes sharpened to 10000grit and the shaving was very thin, almost see-through.  Do our planes need to be that sharp or is that like purchasing a Cadillac when a Chevy would do?

Yes. 

A smoother edge has, by definition, less serrations, and is less likely to fracture in use. In other words, it will last longer.

A smoother edge glides through wood more easily - a "sharper" edge makes working with handtools not only easier, but safer and more pleasurable.

If you are working with softwood end grain especially (such as dovetailing), then edges need to be very sharp. Ditto if you are working with hardwood and planing face grain (to avoid chatter)

If you are working with 1000 grit, then you have not experienced the possibilities of a higher hone. Merry Christmas!


Regards from Perth

Derek