How to flatten your waterstone

[Old CW4]

Find a smooth area of cement around your home, just a couple of square feet will do fine. Sprinkle a handfull of fine masonry sand on the cement and go to it with your stones. Flattens them out in a hurry and being able to make longer strokes, circular, etc. yields a really flat, smooth finish on the stones.

 

[stitchawl]

IMPORTANT!!!!!

If you are using sand, do NOT use beach sand! As Old CW4 says use 'fine masonry sand.' Beach sand is round. Masonry sand is rough and irregular. Beach sand won't hurt your stones, but you'll be rubbing from now 'til next Sunday to get anywhere!

Stitchawl

 

[joepa150]

Find a smooth area of cement around your home, just a couple of square feet will do fine. Sprinkle a handfull of fine masonry sand on the cement and go to it with your stones. Flattens them out in a hurry and being able to make longer strokes, circular, etc. yields a really flat, smooth finish on the stones.

Where do you buy masonry sand and how much is it?

 

[stitchawl]

Where do you buy masonry sand and how much is it?

If you have a cement yard near you, or a construction site, put a baggie in your pocket, go inside and ask any of the workmen for a handful. A large cup-full should last you a few years and they will give it to you for free.

If you have to go to a hardware store or DIY center, you'll probably have to buy a large (25lb+) bag full. Then you can flatten all our stones forever! (But even a large bag shouldn't be more than a few dollars.

Stitchawl

 

[Broos]

Whst grit do you use?

I use the 220 for 2000 and below, and the 600 for the finer waterstones. I agree it may not be the best for the diamond plates, but I've done it for years and they still cut steel like when they were a couple months old. A small price to pay for the convenience and having a very flat, thin, & easy to use flattener. Using them without lube is imo a better way to wear them out faster than necessary p: ducks...).

 

[Knife Outlet]

The coarse diamond plate is the most popular method. Another that works well is a wet concrete block. I've used my basement floor with some success. I normally use a machined cast iron plate on which I sprinkle diamond dust. I like it better than the diamond plate because I'm using fresh, fast cutting abrasives with every lapping session. That means it laps faster with less work. Others have done well with wet/dry sandpaper on a flat surface. I've tried it on the bed of my table saw. That worked just fine but was messy. The bigger the lapping device, the faster things will go.

What stitchawl says about using coarse lapping for fine stones is correct. The idea, for me at least, is to get the stone flattened in the fastest way with the least amount of effort. The coarser the better. Even my Japanese finishing stones get lapped with the coarse grits. They actually seem to cut a little faster after lapping but that wears off pretty quickly.

 

[joepa150]

The coarse diamond plate is the most popular method. Another that works well is a wet concrete block. I've used my basement floor with some success. I normally use a machined cast iron plate on which I sprinkle diamond dust. I like it better than the diamond plate because I'm using fresh, fast cutting abrasives with every lapping session. That means it laps faster with less work. Others have done well with wet/dry sandpaper on a flat surface. I've tried it on the bed of my table saw. That worked just fine but was messy. The bigger the lapping device, the faster things will go.

What stitchawl says about using coarse lapping for fine stones is correct. The idea, for me at least, is to get the stone flattened in the fastest way with the least amount of effort. The coarser the better. Even my Japanese finishing stones get lapped with the coarse grits. They actually seem to cut a little faster after lapping but that wears off pretty quickly.

So I can use a wet cinder block without any negative sideeffects? Wouldn't that be an easy and cost effective way. Why wouldn't everyone flatten the stones this way?

 

[Sparljo]

You will find alot of knife people are not all that interested in the easiest or cheapest way.

You could even forget the waterstone and sharpen on that cinderblock.

Lots of ways to go about it, none wrong unless they are wrong for you.

 

[stitchawl]

So I can use a wet cinder block without any negative sideeffects? Wouldn't that be an easy and cost effective way. Why wouldn't everyone flatten the stones this way?

Sure, a cinder block will work without problems, and so will a flat cement floor or sandpaper on a flat surface or a flattening stone or... or.... or....
For myself, I don't care for the weight of cinder blocks. I prefer to lift sandpaper. And the $15-$25 for a dedicated flattening stone was within my budget. Perhaps the most important factor in my decision to buy a flattening stone was.... I wanted one.

But as for others... perhaps the same reason folks will spend money to buy a pre-made strop of ordinary leather glued to a piece of wood from a shop called "SharpeningKing" rather than paying half that money for a piece of the same leather (but 3x larger) from a company called Widgets.

Different strokes for different folks. :thumbup:
As long as it's flat, and as long as it cuts stone, it gets the job done.

Stitchawl

 

[Knife Outlet]

So I can use a wet cinder block without any negative sideeffects? Wouldn't that be an easy and cost effective way. Why wouldn't everyone flatten the stones this way?

Bulky, heavy and messy in my opinion. A diamond plate is a better solution and not a lot more expensive.

 

[Mickeymoose]

I was using 120 grit SC w&d sandpaper on a granite reference stone to flatten my watertones but I found later that my 1,000-grit stone wouldn't cut metal any more. So I used some 60-grit SC w&d sandpaper and it flattened the stone just fine. It also left my stone in a ripe-cutting like-new state. I think maybe the waterstone was filled up with grit?? Or for some reason it just got filled in and glazed over?? Anyone experience that? Anyway, from your posts, the 60-grit paper seemed to cure both waterstone problems.

 

[KennyB]

Yes, but that doesn't change the grit size of the waterstone, it only changes the appearance of the stone, and after a short bit of sharpening, that smooths out too. Look at a 1000 grit waterstone after it's been flattened on a 220 grit flattener, or as most commonly found, 60-80 grit flatteners. The stone is actually scored quite a bit. But it doesn't affect the sharpening qualities of the stone. Now imagine what a 220 grit flattener does to a 12,000 grit stone... Microscopically, valleys, gouges, and canyons left in the stone, but to a knife blade, it's just fine.

When you sharpen a curved blade, the edge is only contacting a small part of the stone at one time. When a stone is rougher than its grit (as almost ALL stones are after flattening, even on a 220 grit flattener) the blade only contacts the stone in small parts too. Quite bumpy compared to the grit size. But the only thing that results is that it might take one more stroke to achieve the final results. Perhaps two strokes.

Stitchawl

I don't know, it seems that my 1K Norton seems to leave a much more polished finish if I smooth it out on 320 after flattening on 220 or 180.

 

[stitchawl]

I don't know, it seems that my 1K Norton seems to leave a much more polished finish if I smooth it out on 320 after flattening on 220 or 180.

Regardless of the surface condition, a 1K stone will cut at 1K unless you add some different grit to it. Changing the texture of the surface won't change the grit.

If you flatten it with an 80 grit, there will be many scratched depressions below the surface, but still, you only sharpen on the surface. That still remains 1K. But... because of the depressions, you might need to take more strokes to even up the edge to 1K all along the bevel without any missing spots. If you smooth out the stone with a 320 after the 80 you'll have fewer depressions so it will take fewer strokes to even out the edge. The difference might be 20 extra strokes. You can take them on the flattening stone by using a finer grit to smooth the stone after using a courser grit, or you can take them on the sharpening stone evening out the edge. Your choice.

Stitchawl

 

[pwet]

yep

but some stones need a finer lapping to work at their best. shapton pro 5k 8k and above works like crap if flattened by a XXC plate, i used to surface these with a small slotted EF. don't ask me why but i couldn't stand the feel of a coarse lapped shapton polishing stone. finely surfaced was better. still funky feeling but better.

but still produced the same scratch pattern at almost the same rate.

 

[stitchawl]

[SNIP]
but still produced the same scratch pattern at almost the same rate.

Sure. Why would the scratch pattern change? That's a result of the grit size.

I wonder if your dislike of the felt results were more a cause of the rougher sensation while sharpening? Especially as you say the scratch pattern shape and time was the same. Any thoughts on that?

Stitchawl