Sharpening question

[Adam Petersen]

Hello,
I have a hypothetical question. I use norton waterstones to sharpen and currently use a diamond stone to flatten them. Someday that stone will wear out though and I'm just curious if anyone uses the side of a grinding wheel to flatten their stones? Is this something to consider or way off the wall?

Thanks,

Adam

[David Weaver]

How big of a grinding stone? I know George has mentioned several times that they used the side of a sandstone wheel at Williamsburg to true the surface of oilstones.

[Adam Petersen]

I don't know, maybe just an 8" diameter one, maybe a 10". Something like that.

[David Weaver]

You can use anything that is harder than the stone, more or less, and that doesn't embed abrasive particles into the stone.

If you have a hard grinding wheel that you're thinking of, you could use it as a rub stone on the surface of your norton stones to keep them fresh and flat.

[Zach Dillinger]

Or just go to the Borg and buy a concrete block for like $0.97. It works great for flattening stones!

[Jason Coen]

Or just go to the Borg and buy a concrete block for like $0.97. It works great for flattening stones!

It actually does. I didn't believe it until I cautiously tried it, but sho' nuff it worked fine.

[Zach Dillinger]

I tried it a while ago, after a guy at a Midwest tool meet told me about it. I knew that people had used concrete floors for the same task, so why not a portable concrete floor? Cheap, easy and portable. What could be better?

[David Weaver]

Probably better than a floor. The forms for concrete blocks are really really flat, and they have pores all over the surface, so the stone won't suspend itself on a layer of slurry on them.

[Jack Curtis]

Or just go to the Borg and buy a concrete block for like $0.97. It works great for flattening stones!

It certainly does; and if you need a finer surface, try a sidewalk, also unreasonably flat in my case. Of course, you'll leave a few marks.

[Harold Burrell]

It actually does. I didn't believe it until I cautiously tried it, but sho' nuff it worked fine.

OK...seriously? Cinder blocks???

I'm not trying to be smart, I really want to know...

I have been looking at a set of sigmas and (quite frankly) I would be scared to death to start raking those across a cinder block! :eek:

[Zach Dillinger]

Harold,

Yes, seriously, cinder blocks. They work very well for flattening stones. I use a cinder block on my oil stones if they get glazed over or wear a bit hollow, although I'm not the type to get out a straightedge and feeler gauges in the woodshop.

[David Weaver]

OK...seriously? Cinder blocks???

I'm not trying to be smart, I really want to know...

I have been looking at a set of sigmas and (quite frankly) I would be scared to death to start raking those across a cinder block! :eek:

You probably wouldn't want to put the finer stones on a cinder block, they aren't bound nearly as hard as an oilstone and the SP 13k would be wasted by one.

But a cinderblock is a great flattener for coarse waterstones that tend to get graded to a finer grit by a diamond hone, whereas a cinder block with big pores and coarse media floating around on it will not do that.

IF you're worried about flat on the cinder block (I haven't seen a new one that's not flat on the sides), you could always take a steel ruler from one part of a building supply store to the cinder blocks and confirm that they're flat both in their length and on the diagonals. In reality, once we notice that our stones are out of flat, they are much more out of flat than that.

[Adam Petersen]

Thank you for the replies. Curious, how does this strike you.....flatten my norton 220 on a cinderblock and my other stones with the norton 220?

[David Weaver]

The norton 220 is a soft stone. I don't know how well it would work to condition other stones, but if you do have three stones, you can certainly rub the three together. A friable coarse stone is fine to use with finer stones.

Even if you only rub two stones together, if they are similar hardness, you should be able to get two flat stones, and if they are not, you still have the concrete block to keep the surface of the 220 true.

[Jim Riseborough]

Hello,
I have a hypothetical question. I use norton waterstones to sharpen and currently use a diamond stone to flatten them. Someday that stone will wear out though and I'm just curious if anyone uses the side of a grinding wheel to flatten their stones? Is this something to consider or way off the wall?

Thanks,

Adam

Can you put some paper down on a granite flat stone and work across that?

[george wilson]

I taught them to use the side of their sandstone wheels. Every shop had one. I came into the gunsmith's shop and this apprentice was trying to flatten their black Arkansas stone with a piece of 600 wet or dry wrapped around a file!! He'd still be there today if I hadn't showed him the trick!! I doubt that the soft sandstone was even as hard as a black Arkansas stone. Maybe the sand particles are. But somehow,it worked pretty rapidly,too.

Use of a cinder block is also a proven technique though the thought of it tends to make you cringe! You might could find off cuts of sandstone for free or cheaply if you have an architectural stone co. nearby. Perhaps a tombstone co.would do.

[Andrew Pitonyak]

Can you put some paper down on a granite flat stone and work across that?

Although some here will say yes, you can use sandpaper, and many here do exactly that. I will even admit to having done it. But, please read this:

http://www.sawmillcreek.org/showthread.php?175329-How-do-you-flatten-Japanese-Water-Stones&p=1803493#post1803493

[george wilson]

I only use hard stones,and my method works fine. But,for soft stones,best listen to Stuart T.. Nothing is getting imbedded in an Arkansas stone,or in my ceramics(haven't used other stones for over 20 years by now).

[Stuart Tierney]

I only use hard stones,and my method works fine. But,for soft stones,best listen to Stuart T.. Nothing is getting imbedded in an Arkansas stone,or in my ceramics(haven't used other stones for over 20 years by now).

It's not quite 'soft stones', as they tend to be fine with sandpaper and it's actually encouraged by the makers of softer stones. By those I mean most King, all Norton and some Naniwa and Suehiro 'water' stones.

The problem lies with using sandpaper on those stones that are harder than a traditional 'waterstone' but softer than an oilstone or those Spyderco things.

Harder stones are unlikely to pick up any stray bits of grit or garbage, as they're so hard. Softer stones will pick up the garbage, but they'll also release it freely and quickly so it doesn't have a chance to hurt your blade. The 'middle' hard stones can and will pick up loose abrasive grains if given an opportunity, but they won't release it easily so you're happily working away, putting great gouges in the blade because what you thought was a #5000 stone (with 2-3 micron particles) has a piece of #200 in it, and #200 is up around 40 microns IIRC.

Think 'used kitty litter' and you're about right regarding the size difference.

The cinder block can do the same thing, but tends not to in my experience. However, most of the stones I own that should NEVER be flattened with sandpaper will also tend to grind down a cinder block or concrete pretty quickly. Yeah, I've tried it. If sandpaper will work, so will a cinderblock. If the label on your stone is King or Norton, go your hardest. If it's not one of those two or of similar composition, then good luck with that. Also forward me your email address so when the poor sap who took your well intentioned (but completely misguided and occasionally idiotic) advice runs into problems and asks me to help.

I really do wish that when folks go to the effort to write what they're using, they'd also take a few seconds to write down what stones they're actually flattening with these methods. But that'd be asking too much I suppose, so folks are running around thinking they can flatten their nice new 'ceramic waterstone' with some sandpaper because someone said "that's how I do it, you don't need those expensive diamond plates or whatnot!", not mentioning that they're flattening some soft, coarse green piece of snot with sandpaper and that the shiny new 'ceramic stone' will turn their 'waterstone' into mush without breaking a sweat.

But hey, what do I know?


Stu.