How to flatten coarse stones?

[pedder]

Start here
Loads of examples. But very variable. Some are not even Japanese and are using "transitional" methods. But you can see clearly in many of them that they are using the whole face of the stone. Some of them can be seen to freshen up the surface with a quick pass of something or other, but this isn't quite the same as "flattening"
These are mostly water-stones but you do the same with oil stones.
Re telling how to do in a few words how many words are needed in addition to using the whole face of the stone, spreading the wear etc? What is there to explain?
It's similar to flattening a piece of wood - to avoid making a hollow, or a hump, you work on reducing the high points - or better still - spread the work so you don't create them in the first place.

PS chisel sharpening jap style here
This chap seems to have done a load of videos using different sorts of stones and tools.

Here's another. He starts by freshening the surface and then proceeds to use the whole face - changing position and shooting right off the ends.
There's loads of them and an interesting voyage of discovery if you open some of the links to the right. Could take you anywhere!

http://www.youtube.com/watch?v=g69Xj7u3 ... re=related

Thanks, that helps. I think freshen up is "flattening" just little by little.

Cheers
Pedder

 

[Jacob]

........
Thanks, that helps. I think freshen up is "flattening" just little by little.

Cheers
Pedder

Well yes, that and distributing the wear over the whole stone. Basically just keeping a stone in trim and usable as you go, rather than blindly hollowing it out and then going for the full crazy sharpening scenario involving granite slabs, flagstones, stacks of plate glass, etc.

Come to think that is the basis of crazy sharpening - first you spoil your tools and stones, then you apply major surgery to mend them, with the aid of various expensive gadgets! You can see why the tool trade like it.

 

[pedder]

Come to think that is the basis of crazy sharpening - first you spoil your tools and stones, then you apply major surgery to mend them, with the aid of various expensive gadgets! You can see why the tool trade like it.

Hi Jacob,

I use an extremly cheap flattening installation, you will like it:

Three slottetd bricks flattened like lenses by the old maker.
First flattening on a sidewalk stone:

10 seconds of refreshing/flattening before each sharpening keeps the stones flat. And I do use a 10€ sharpening helper.
Cheap enough?

Cheers
Pedder

 

[Jacob]

So - you flatten a stone with a brick and then flatten a sharpening stone on the stone and then sharpen your tools?
Rather a lot of stages! How do you flatten the bricks?

 

[pedder]

So - you flatten a stone with a brick and then flatten a sharpening stone on the stone and then sharpen your tools?
Rather a lot of stages! How do you flatten the bricks?

1. cut slotts in 3 bricks
2. initial sharpening of the 3 bricks on a side walk stone
3. Lense making flattening: flatten brick 1 on 2, 2 on 3, 3 on 1. Repeat until dead flat (flatter (?) than any diamond plate can be )
4. flatten the stones on the bricks

Repeat 3 when the brick run out of flatness

When the waterstones are very unflat, I use step one with the sone instead of the brick.

Totals cost 10 €, total worktime for the first flattening: 1 hour saved me 90€ in one hour. The only thing I dislike: the brikes are heavy.


You have more money and less time: Use Bernhards setup:

slotted granite window sill

Cheers
Pedder

 

[Jacob]

I'm sure the above both work perfectly.
Alternative 3:
If you don't want to spend any money at all and want to do things even more quickly, don't do any of the above - just keep your stone flat as you sharpen!

3. Lense making flattening: flatten brick 1 on 2, 2 on 3, 3 on 1. Repeat until dead flat (flatter (?) than any diamond plate can be )

That's also the trad way of making a perfect straightedge (Whitworth discovered it though he certainly didn't invent it). Luckily woodworkers don't require anything like that degree of accuracy!
I guess I'm talking of flat enough rather than perfectly flat

 

[pedder]

He made a point to flatten your stone before each sharpening! Just a few swipes with a coarse DMT in his case.

I do the same but just every now and then with a Diapad. But not to flatten (though it will a bit) but just to freshen up the surface

Jacob,

did you get your Diapad for free? They cost about 30€.

See? Your freshen up (and unintentional flattening ) is more expensive than mine.

Cheers
Pedder

 

[Jacob]

He made a point to flatten your stone before each sharpening! Just a few swipes with a coarse DMT in his case.

I do the same but just every now and then with a Diapad. But not to flatten (though it will a bit) but just to freshen up the surface

Jacob,

did you get your Diapad for free? They cost about 30€.

See? Your freshen up (and unintentional flattening ) is more expensive than mine.

Cheers
Pedder

No I bought a set for another job (cleaning up an old marble fireplace). £7 here though I paid more. They do seem to last forever. They are flexible so don't flatten too well.
I guess another bit of coarse stone or emery paper would do the job - I just happened to have a diapad already.
It's not only the cost - it's mainly the speed.

Another non-essential but useful accessory is a rare-earth magnet, for removing swarf and keeping things clean.

PS so to sharpen one blade you first flatten your sharpening stone by flattening three bricks and flattening a paving slab. It certainly must speed things up! :lol: What about flattening three paving slabs whilst you are at it? Then you'd get it all done in no time at all. :shock:

Another PS - Pedder, have you ever considered stonemasonry as a career?

 

[GazPal]

British Standards tolerance for paving slabs/stones is circa +/- 3mm per 900mm run and the same criteria applies to block pavers/paving blocks, soo they're not necessarily the best flattening medium.

 

[bugbear]

That's also the trad way of making a perfect straightedge (Whitworth discovered it though he certainly didn't invent it).

The big change Whitworth made was to scrape instead of lap, and he was making flat surfaces, not straight edges.

BugBear (fan of the great Whitworth)