need some opinions on a new water stone

[dan sherman]

My GF, is asking for a list of possible gifts for my birthday, so obviously a new water stone is the first thing that came to mind.

Currently my system is as follows.

1. 1k Sigma Power Select II
2. 5k Naniwa Super stone
3. 8k Naniwa Super stone
4. 0.5 micron honing compound on hard maple

When sharpening it's usually 1k, micro bevel at 8k, then compound. This produces a very sharp blade, but I think it could be better. I feel as if the 8k to compound jump is to great and really isn't doing a whole lot other than making a shiny surface.

I have been pondering a 13k Sigma power ceramic to either replace the 8k, the honing compound, or maybe both. What do people think would the 13k be a good purchase?

[Chris Griggs]

The sig 13k will definitely get you sharper than the 8k. In theory the compound will get you as fine or finer an edge than the 13 (depending on what it actually is), but in practice the 13 may get you a sharper edge because is easier to use and easier to keep uncontaminated.

Its an excellent stone period, and even more excellent for the money at the current exchange rate.

[David Weaver]

If that setup isn't doing it for sharpness, something's not working right in the sequence. That should do as well as any setup can, but if the maple is contaminated or not uniform, that could be part of the problem.

The 13k sigma will only solve the problem if there's something wrong with the process. The green paste with al-ox leaves a similar edge to the sp 13k, and the pure green (chromium oxide compound only, no aluminum oxide) is finer than the 13k. MDF might be a better substrate than maple, though - at least it is to me.

[dan sherman]

It's most likely me not having the patients to let the compound do it's job. I have a mix of 01 and A2, and some times it seems like the compound really isn't accomplishing that much, specially in the A2.

[David Weaver]

Put a liberal amount on the surface of the maple next time and add a few drops of oil to the surface if you're not doing it already. Those waxy sticks are made for buffs where the buff creates heat, and a little bit of oil cuts them into something much more useful when you're working it by hand.

Those sticks are actually very aggressive if you can get the abrasive free from the wax.

[Kees Heiden]

I would put a 400 stone on your arsenal. Sometimes the 1000 Sigma takes just too much time, and a few swipes on my Bester 400 brings up the burr very quickly.

My finest is also an 8000 superstone. I'm happy with it. When I want a really good edge, I use a 4000 before the 8000. That seems to improve things.

[Matthew N. Masail]

Since you mention that the improvement your looking for is in the final edge I would agree with Kees - a middle stone something around 2k 3k might be best - look at the scratches after you use the 8000, are they all gone? using a medium stone was another revelation to my sharpening.


another thing to consider is a plain leather strop.... tried one the other day after the MDF+Green stuff and it knocked my socks off...


David is right about the wax... I don't know how it can be used as a rub on? ! :confused:... ! I heat up the a tiny bit of green stuff with a little baby oil over a stove and when it's melted (not too hot) I wipe in on with a lint free cloth or something. I like MDF.


Kees, Just as a note for the 400 stone, I have the sigma 1200 and find it too slow in bevel work too.... I thought about a lower grit but the new carex 1000 (the blue one) will get a burr faster than you can say burr... and it's on the hard side too, doesn't dish much and good feel.

[Steve Voigt]

I'm not a waterstone user, but I just have to say that my absolute favorite "stone" is a piece of soft maple with the green chromium/al ox paste. I'm not trying to be clever; I just really am always amazed, everytime I use it, that it gets the job done for next to nothing.

[dan sherman]

I should probably be a little clearer.

I'm using a guide (veritas MK II) with the following steps.

steps:

1. if the edge is really bad hit it with the grinder (bevel is in the 25 to 27 degree range.)
2. 1k stone with the angle set to 30 degrees
3. 8k stone with the angle set to 32 degrees
4. 0.5 micron compound with the angle set to 32 degrees

My concern is that the the compound takes longer than i think it should to remove the scratches from the 8k stone.

[Malcolm Schweizer]

Since she's buying, you could go for the Shapton glass 30,000 grit, whic is 0.48 microns. I found this on a machinist site and saved it for reference as to how small a micron is. I apologize, I have no idea where I originally found it.

[David Weaver]

There's something fundamental that's not occurring with that regimen. It should work well and the 8k scratches should be removed completely in about 10 strokes.

You might want to try a clean smooth oiled leather strop after the 8k and see haw the edge is at that point. It should be acceptably sharp for anything with the wire edge removed.

Clean leather .means like nothing on the leather. No wrinkles, colored tanning treatment or anything else like that.

[David Weaver]

By the way, for the folks who like compounds and who manage to keep their tools ground, McMaster carr has some big 3 pound bricks of compound, I just don't know how fine their fine compounds are.

Out of curiosity, I bought a mid-grit yellow compound to see how well it would work as a one-step honing compound (sort of like you'd do with washita). I like the washita better for softer vintage irons, but the yellow is capable of working totally by itself if you use a little skill and work with it.

4784A2 in McMaster's catalog - 3 pounds for 10 bucks, and they didn't skimp on the abrasives in it, and it's not ridiculously hard. If you're close to a mcmaster, shipping is usually very cheap. it was a little over five bucks for me for four bars of stuff.

http://www.mcmaster.com/#buffing-bars/=oqy6as

Of the other bars, two were plastic polishing bars, but I did try the cut and color tripoli and it's sort of bizarre given you expect tripoli to not be aggressive. The (finest grade) color only triploi might be gentle, but the cut and color combined is anything but.

(of course, i'm not affiliated with mcmaster carr, i'm just fascinated with sharpening).

[Brett Bobo]

1. if the edge is really bad hit it with the grinder (bevel is in the 25 to 27 degree range.)
2. 1k stone with the angle set to 30 degrees
3. 8k stone with the angle set to 32 degrees
4. 0.5 micron compound with the angle set to 32 degrees

Hi Dan,
Is it correct that you set three angles in your sharpening--a primary bevel, followed by secondary and tertiary micro bevels? What's the advantage of two micro bevels,instead of just one? I follow the exact same procedure with great results, including stropping on maple with compound, except I add a 4000 grit stone into the mix.

[dan sherman]

David, I'll get a shot of the compound block when I get home tonight. Also, have you tried any of the CBN sprays I have seen them as low as 1/8th of a micron.

[dan sherman]

Hi Dan,
What's the advantage of two micro bevels,instead of just one? I follow the exact same procedure with great results, including stropping on maple with compound, except I add a 4000 grit stone into the mix.

I feel it's faster, because instead of using a fine grit to remove scratches left by the previous girt, you are just creating a new facet, and thus a new edge. An added bonus is that you barely use your most expensive stones.

[David Weaver]

Actually, I do have a CBN slurry for razors. It gets a lot of positive press, but I think that chromium oxide (pure powder) and iron oxide (pure powder) are better for razors.

Anything that doesn't cut pretty fast is not practical for woodworking tools, though (because you wear off a huge amount of steel in a few swipes of a plane, etc), and those tiny particle slurries don't cut fast enough for my taste. They are often designed for something like razors or for polishing where not so much of an abrasive density is warranted.

the dense slurries of CBN are very expensive, too, and on top of that tend to be marked up even more due to sales of them by gurus who are just another layer of cost, in my opinion. CBN's role is best as a high speed substitute for diamonds, which are not compatible with steel when grinding speed creates heat. They are, in my opinion, an overpriced solution for tools as diamonds are much cheaper and there is no limitation due to heat in hand honing, so the weakness of diamonds in dry power grinding doesn't exist.

For finishing compounds, I think the following are good:
* Dry chromium oxide powder (1/2 micron) - there is no al-ox in it
* autosol polish (which appears to be 3 micron or so aluminum oxide - an MSDS would probably confirm that)
* yellow 3 micron al-ox buffing sticks (sold to carvers, very overpriced and probably just made by osborn or one of the buffing compound makers - there's probably a 3 pound stick of the same thing available somewhere for ten bucks)
* 1 micron or 1/2 micron diamonds

I do, however, think there is a lot of virtue in teasing sharpness out of something a little more coarse using a clean vegetable tanned bare leather strop so as to decrease the time it takes to get a finished edge. If I am using two stones to maintain an edge (which is usually a shapton 1k and 15k), i probably spend a minute total on the two with a plane iron, and if using something like just a washita, less than that. Add a minute or so to get a plane apart and put it back together. Much more time than that, and it becomes a hindrance. I never use more than two stones, no matter what the two are.

Sometimes you have something sharpened well, but in a steel like A2 it's holding a little bit of scuzz on the edge making it seem less sharp than it is. A piece of clean bare leather gets that off and lets you know whether the edge really isn't sharp, or if it's just that a wire edge is facing up into the direction you're testing a cut.

[Brett Bobo]

Put a liberal amount on the surface of the maple next time and add a few drops of oil to the surface if you're not doing it already.

Hi David,
Do you have a particular oil that you recommend? Do you recommend doing the same thing to leather? I've been using mineral oil as a lubricant and it seems to work well.

Thanks,
Brett

[David Weaver]

Mineral oil is fine. I don't like it soaked all the way to the other side when I put it on the smooth side of veg. tanned leather, but I like enough so that I can wipe metal swarf off of the leather and keep it clean. Neatsfoot or mineral oil are both fine.

[dan sherman]

When I got home tonight, I found the box my honing compound came in. It's made by Formax (I purchased if from LV).

after some internet digging, I found some MSDS info.

20% - 30% chromium oxide
50% - 60% aluminum oxide
15% - 17% triglycerides & talllow derivatives
3% - 5% wax


So is sounds like I need to decide between a truly fine stone or finding a better compound. Anyone have a source of better honing compound?

[David Weaver]

You really don't need anything finer than that compound. The edge that you get with it is similar to a sp 13k edge. You can go into the razor compounds (look up 0.3 micron and 0.5 micron graded chromium oxide powder), but they will cut more slowly. I don't know if cutting faster is the only reason the larger aluminum oxide particles are in that honing compound, but that's probably one of the reasons. the graded razor powders will probably cut about 1/3rd or 1/4th as fast.

I have had good experience buying powder from star shaving, but I saw something on a razor board a month or so ago that the guy was overly busy with his real life job. Figure that star sells it for about 3-4 bucks an ounce for the powder, and you can use baby oil or plain mineral oil to make a paste out of it.

[Chris Griggs]

My experience is the same as Dave's with the uber fine compounds. The .5 micron pure CroOx does lovely things to an edge, but you really need to use it following something like an 8k stone, and be sure you've done a good job with that stone. Whereas with something like the stick that have 1 micron AlOx in them you can go straight from some thing like a fine india or washita and get a great edge if you just work a new micro bevel. Yes the graded .5 micron pure CroOx will get a finer edge, but the improvement over a decent 1 micron honing compound won't be that noticeable for *most* work and will get knocked off after a couple strokes anyway. Not saying not to use the pure CroOx, but there is a trade off, and honing compound sticks like LV stuff (and TFWW I think and other common ones) that are labeled as .5 micro +- .5 micron (so really they're 1 micron) will give you a very fine edge if used correctly and will cut a good bit faster than the ultra fine pure graded stuff.

Anyway, my guess is that the problems you are experiencing are coming from a contaminated substrate. Get some fresh MDF or glue some cereal box cardboard down to your maple block so you KNOW you have a clean surface and try again with the stuff you already have.

...OR just get a Sig 13k. Really do whatever makes seems simplest to you and makes you happy.


(Oh and if you want to try some pure CroOx this place (http://shop.starshaving.com/product.sc;jsessionid=2A0F01C4FEB0556C7E6D69B55014 6C3F.m1plqscsfapp03?productId=8&categoryId=1)sells a bag of pure powder for a pretty decent price. You can likely get more for the same cost from a pigment supplier but you'll never use a 3oz bag anyway.

[Malcolm Schweizer]

...that are labeled as .5 micro +- .5 micron (so really they're 1 micron) will give you a very fine edge if used correctly and will cut a good bit faster than the ultra fine pure graded stuff.



...or if they err in the other direction, they could be ZERO microns!!!! :eek:

[Chris Griggs]

...or if they err in the other direction, they could be ZERO microns!!!! :eek:

:D Yes, zero micron compound is the only way to achieve true zero radius cutting edge.