Flattening waterstones with fine sand possible?

[Jacob]

Yes, great to se you back David, I look forward to seeing you at a show some time!

Jacob, one word. Nonsense.
I have never seen a stone that has been worked convex by honing! I assume you have examples of this to show us all?
The concavity issue is pretty common, but you seem to be unable to admit the fact. I'd guess that anyone buying a well used secondhand stone putting a straghtedge over it would see a degree of dishing.
I'm sure you make these comments for arguement, they certainly seem to lack rational thought - only a CNC type operation could take any tool to the extremeties of a stones surface and distribute the pressure evenly each and every time, unless you are the one exception to the rule.

Andy

Lots of people regularly flatten wood, stone, other materials, by hand (and eye) it's totally normal. The main difference when you are sharpening is that you are holding the tool at about 30º.

 

[andy king]

Lots of people regularly flatten wood, stone, other materials, by hand (and eye) it's totally normal

Yes, they do, but as you well know and understand, (but seemingly refuse to accept) they do so using other tools and abrasives to achieve it.
The stone used for honing is the device used to achieve an edge and the consequence of running a chisel, plane iron or whatever against it eventually results in it wearing away. It's a trade off. The tool being honed isn't there to dress the surface of the stone as a by product, it's there to attain an edge. Nothing more.
The argument that you can keep a stone entirely flat by how and where you hone on it is nonsensical, and also illogical, but you love to simply continue in this vein until someone ends up feeling the wrath of the moderators for rising to your bait.
I asked for evidence of convex stones, and i'd like evidence of how a stone, India, natural Japanese or otherwise can be kept mirror flat by honing to the extremeties as you say.
I doubt that claim, but i'm always happy to be proven wrong with evidence, and will be happy to apologise once I see it can be done to perfect flatness as you say it can be.
Not your usual 'try it yourself' answer please, you say it's done and can be done, please prove it!!!

Andy

 

[Jacob]

"Mirror" flat is a step too far - we are talking about hand processes here.
I suggest you try it yourself. It takes some time to get from hollow to reasonably flat, by sharpening alone, but if that is what you want it is perfectly possible.

PS I just checked the stone I use most often. It's very slightly concave along the length. but it's slightly convex across the width - you can just see light under a straight edge at the edges.
I could correct for both of these (over time) if I wanted to but it's OK as it is. I've obviously been over correcting for across the width, to avoid the dreaded hollow!

Honing to the extremities as you say, would be difficult. In fact you hone off and over the edges (if you want to).

 

[andy king]

I suggest you try it yourself.

Which is the one thing I said not to say...
BUT... The OP asked if he could flatten using a certain type of sand, and your response was to say

If you sharpen carefully you don't ever need to flatten your stones.
Saves a lot of bother!

But you make such statements regularly on many subjects and never qualify them when challenged for proof or evidence of the technique, procedure, whatever.
The idea of offering advice is to actually help the person achieve or answer their question, not just make a vague comment without backing it up.
If, as you say, this is done, then there would be very few hollow/dished old stones out there from years gone by, but it tends to be the opposite, very few flat ones, and those that are have had very little use, and/or are exceptionally hard so wear very little.

Andy

 

[Jacob]

I suggest you try it yourself.

Which is the one thing I said not to say...
BUT... The OP asked if he could flatten using a certain type of sand, and your response was to say

If you sharpen carefully you don't ever need to flatten your stones.
Saves a lot of bother!

But you make such statements regularly on many subjects and never qualify them when challenged for proof or evidence of the technique, procedure, whatever.
The idea of offering advice is to actually help the person achieve or answer their question, not just make a vague comment without backing it up.
If, as you say, this is done, then there would be very few hollow/dished old stones out there from years gone by, but it tends to be the opposite, very few flat ones, and those that are have had very little use, and/or are exceptionally hard so wear very little.

Andy

I just added PS to my previous post with a bit of proof.
Re sand - I suggested two stones instead, in a post above.
Re old hollow stones - freehand sharpeners don't mind a bit of a hollow so that's why you find so many. After all it's no problem to flatten them if that is what is wanted, as we all know!

 

[Jacob]

To those who say these things are impossible; would singing help?

"With a lift of her chin and a bit of a grin,
Without any doubting or quiddit,
She started to sing as she tackled the thing
That couldn't be done, and she did it."

http://monologues.co.uk/Parodies/It_Couldnt_Be_Done.htm

Not sure what a quiddit is but you can probably get one from Axminster. :roll:

 

[Alf]

Believe me, I hate myself for saying this, but I'm afraid there is evidence that yup, you can keep an oilstone flat enough solely by how you use it. Here ya go. (And look, don't tell Jacob, but I haven't flattened my oilstones in ages either, and they're, um, fine. Wouldn't call them mirror flat though, if that helps.)

And excellent to see you, Mr C! You must be feeling better to wade straight into sharpening fun and games with Jacob.

Oh, and to the OP - I am of no practical use at all. Sorry.

 

[andy king]

Believe me, I hate myself for saying this, but I'm afraid there is evidence that yup, you can keep an oilstone flat enough solely by how you use it. Here ya go.

Somehow I can't imagine Jacob doing his 'rounded under bevel' regime like this! :lol:
Definitely a long drawn out affair, i'd have half a dozen tools honed by the time he took - it certainly looks there was a glitch or two in the video to keep the timeframe down... (there's also a comment of the stone being 'dished a little' where he hasn't practiced what he preaches)

(And look, don't tell Jacob, but I haven't flattened my oilstones in ages either, and they're, um, fine. Wouldn't call them mirror flat though, if that helps.)

Nope, I don't doubt it Alf, and i'm not referring to having to flatten regularly, simply that over the course of time, standard honing practices will invariably lead to hollowing.
I used the same double sided Norton India stone from my apprentice days up until about 20 years later, and that was showing signs of hollow when i dropped it so the wear rate isn't huge considering it was used many times a day over that period. Different stones will be different of course.
I replaced it with an identical India stone but then had the problem that all the backs of my tools conformed to the old stone so I had to flatten them all back.
I now use a Trend diamond stone as it keeps everything flat, and remains so, and any new tools I put on it are easily licked into shape, and the backs remain flat, not conformed to a shaped stone, plus it's fast, clean and gives a great edge with no mess or fuss.

cheers,
Andy

 

[Jacob]

.....
over the course of time, standard honing practices will invariably lead to hollowing.....

Andy

Depends what you mean by standard honing practice. My standard honing practice won't lead invariably to hollowing (unless I want it to).
What about the two stones answer to our OP's prob? Struck me as a goodun. Might even try it myself one day! Probably won't work well with oil-stones (too hard) but I bet it would with soft water stones.

 

[CHJ]

Please give it a rest folks, some of us don't have the option to ignore this continual 'he said, I said’ type banter and it is getting very annoying and boring in the extreme and is of no benefit or contribution to the opening posters original request for guidance.

 

[bridger]

What about the two stones answer to our OP's prob? Struck me as a goodun. Might even try it myself one day! Probably won't work well with oil-stones (too hard) but I bet it would with soft water stones.

two stones worked against each other will produce a surface on each that is the opposite of the other, but almost invariably not flat. what will be required is a third stone, doing the work with alternating pairs, rotating the stones against each other periodically. oh, and the stones must be the same hardness and grit. it doesn't matter how hard or what grit, just the same.

what woodworker has 3 of the same stone? someone who teaches sharpening, perhaps... much easier to flatten to a reference surface.

 

[Jacob]

What about the two stones answer to our OP's prob? Struck me as a goodun. Might even try it myself one day! Probably won't work well with oil-stones (too hard) but I bet it would with soft water stones.

two stones worked against each other will produce a surface on each that is the opposite of the other, but almost invariably not flat. what will be required is a third stone, doing the work with alternating pairs, rotating the stones against each other periodically. oh, and the stones must be the same hardness and grit. it doesn't matter how hard or what grit, just the same.

what woodworker has 3 of the same stone? someone who teaches sharpening, perhaps... much easier to flatten to a reference surface.

Two will do. Yes to rotating.
much easier to flatten to a reference surface. Why?
Two stones also saves; having to find or buy a reference surface and the accompanying paraphernalia of grinding sand etc., and having to flatten a reference surface.
Also the second stone can be used for (guess what) sharpening!!! This means twice as long between flattenings and double the life of your stone. Win win win!

 

[Alf]

Believe me, I hate myself for saying this, but I'm afraid there is evidence that yup, you can keep an oilstone flat enough solely by how you use it. Here ya go.

Somehow I can't imagine Jacob doing his 'rounded under bevel' regime like this! :lol:
Definitely a long drawn out affair, i'd have half a dozen tools honed by the time he took - it certainly looks there was a glitch or two in the video to keep the timeframe down... (there's also a comment of the stone being 'dished a little' where he hasn't practiced what he preaches)

I think there might have been just a hint of sarcasm there in the dishing comment, Andy. Given the feeler gauge result (which seems to me to be the practical proof I thought you wanted). But I must have misunderstood the argument. I thought it was "You can't keep an oilstone flat just by regular honing use alone" and I thought 25 years (as opposed to my measly 6 or 7) would kinda prove that, um, yes you can. So, er, well I shall just go away again because obviously I've got it hopelessly wrong.

Chas, perhaps if you removed the common denominator to the "he said, I said" stuff, you might get some peace. And so would we. Either that or you need to genetically alter the whole male gender to enable them to say "I was wrong" without spontaneously combusting. Actually, if you could do that anyway... :wink:

 

[ali27]

Jacob, two stones cannot produce a flat surface. You need a third stone
and as has been mentioned correctly, they need to be the same hardness, grit.
What two stones can do is that if you sharpen a slightly concavity in both lengthwise,
by rubbing them together this concavity is reduced. Not sure what happens in the width
of the stone. You wrote that your stone has slight convexity in the width. That is not good
as your plane iron will rock left to right ever so slightly.

Jacob, just for trying something completely new, flatten your oil stones with some
wet and dry. Draw some lines and start flattening. After your oilstones are flat, sharpen
a single plane iron or chisel on them and come back and tell us the result.

25 years using an oilstone without flattening it and still having a flat surface?Hmm, first
I don't believe the stone hasn't been flattened in 25 years(Mr Schwartz can't prove that),
second thing is I am not sure I would take a woodworker seriously if he hadn't flattened his
sharpening stone in 25 years :lol: I mean how difficult would it be to do it once monthly?
Am I supposed to believe this Mr has a succesful method which allowed him to sharpen
his tools for 25 years on an oilstone and keeping it flat within a thou or so? I have a hard
time believing this. Maybe if one would use a straightedge frequently to check flattness and
with having that knowledge sharpen on the high spots to bring back flattness.

I have never used an oil stone. If a stone would be super dish resistant then maybe all it
would require is an occasional(once a week with regular use) flattening.

 

[Benchwayze]

The last time I flattened my water-stone I used half a sanding belt from my Bosch sander, taped down to a chunk of 25mm MDF.
I flattened the stone dry, so no problems with the MDF getting wet.

Were I to flatten the stone wet, I would probably use Melamine surfaced board, but the dry flattening worked perfectly; and it was fast. I was back on the stone, 'wearing it hollow' again in five minutes!

Edit...
I removed the 'clogging' from the sanding strip, with an old paintbrush; just in case anyone comes back on that!

HTH
John

 

[Jacob]

Jacob, two stones cannot produce a flat surface. You need a third stone
and as has been mentioned correctly, they need to be the same hardness, grit.
What two stones can do is that if you sharpen a slightly concavity in both lengthwise,
by rubbing them together this concavity is reduced.

Sort of correct in theory but in practice you LOOK at what you are doing and correct accordingly e.g. make more effort to remove high spots

Not sure what happens in the width
of the stone.

It's entirely up to you. You are in control. You monitor progress by LOOKING

You wrote that your stone has slight convexity in the width. That is not good
as your plane iron will rock left to right ever so slightly.

Not if I don't let it! I am not a robot, are you?

Jacob, just for trying something completely new, flatten your oil stones with some
wet and dry. Draw some lines and start flattening. After your oilstones are flat, sharpen
a single plane iron or chisel on them and come back and tell us the result.

Done it (once). Found that my nicely cambered plane blades were harder to hone. Didn't bother doing it again. No point that I could see.

25 years using an oilstone without flattening it and still having a flat surface?Hmm, first
I don't believe the stone hasn't been flattened in 25 years(Mr Schwartz can't prove that),
second thing is I am not sure I would take a woodworker seriously if he hadn't flattened his
sharpening stone in 25 years

Oh dear - you aren't taking me seriously. I'm so upset! :lol: :lol:

I mean how difficult would it be to do it once monthly?

Easier not to bother, and a waste of good stone

Am I supposed to believe this Mr has a succesful method which allowed him to sharpen
his tools for 25 years on an oilstone and keeping it flat within a thou or so? I have a hard
time believing this.

So I gather! The secret is in LOOKING at what you are doing, applying a straight edge etc and correcting your procedures to achieve the degree of flatness you feel need

 

[CHJ]

.......I have never used an oil stone. If a stone would be super dish resistant then maybe all it
would require is an occasional(once a week with regular use) flattening.

About 1964 I was presented a 'fine' new oilstone mounted in a wooden case he made for it by a cabinet maker as a thank-you for help with a job. I have just been out to the shed to check, it's a small 6" X 1-1/2" and is mounted with run-off blocks/wedges each end. It has a max of 4 thou. depression in the middle-lengthwise and no detectable other than the slightest glimmer of light dishing in the width, both depessions are constant curve and even. It has never been flattened and has been used and abused as often as needed in all those years, only in a home workshop mode admittedly and not for a wage earner.

My chisels and planes may not be tuned and sharpened to the high standards that others here aspire to, in fact I know full well they are not, but for carpentry as opposed to fine cabinet work they have served me well.

 

[Derek Cohen (Perth Oz)]

To the OP ...

Stop using loose grit to flatten your waterstones! It is not only archaic, but a time-consuming and unnecessarily inefficient.

Get a diamond stone - about 325 grit (extra coarse) - and use that instead. It is quick, convenient, reliable, and will last forever if you keep it just for the waterstones.

Regards from Perth

Derek

 

[Benchwayze]

You can avoid a bad dish in the middle of a stone, by using different paths across the width of the stone, especially when honing chisels.
But I don't see how one can avoid dishing the stone along its length to a certain degree, (Figure of eight honers in particular) because it''s virtually impossible to use the FULL length of the stone. Only by turning the stone end for end can you compensate, but whatever you do, you do have to flatten occasionally. The amount of labour depends on how long you let it go between flattening sessions!

Well so I found anyhow!

There's a way for everyone that is sometimes gonna be different to someone else's method. So let's accept that eh?

 

[Benchwayze]

To the OP ...

Stop using loose grit to flatten your waterstones! It is not only archaic, but a time-consuming and unnecessarily inefficient.

Get a diamond stone - about 325 grit (extra coarse) - and use that instead. It is quick, convenient, reliable, and will last forever if you keep it just for the waterstones.

Regards from Perth

Derek

Derek,

There's them wot sez using hand tools exclusively is 'archaic', but I would ignore them, if I was a 'galoot'... :lol:

Loose grit is the best way to make a parabolic mirror, for sure; albeit a bit archaic. And it sure was time consuming, but great fun.

Cheers Derek.

John :wink: