Flattening Waterstones... I think I like this Norton Thingie

[Erich Weidner]

All the articles I recall reading and the guides from Veritas and Lie-Neilson suggest using a diamond grit plate (or glass plate and sandpaper, or granite block and sandpaper). Can't say I recall reading anywhere about this, but I bought one when I was out of town visiting family and needed to flatten a combo waterstone I had left with my folks years before. (The state of the kitchen knives' cutting edges was not pretty).

I ordered this thing (from a popular 2 day shipping online merchant)... https://www.nortonabrasives.com/en-u...attening-stone

It worked so fast, I ordered one for myself back home and have not touched my DMT diamond lapping/flattening plate since.

Anyone else use this? What do you prefer?

[Mike Henderson]

That Norton flattening stone has some serious problems. Your working stones tend to dish in the center so when you "flatten" them on the Norton stone the Norton stone tends to become convex. To make the Norton stone work you have to keep flattening it. And to do that you need something like a diamond plate (I use the DMT diamond plates). If you don't flatten your Norton stone, you'll eventually be putting a concave surface on your working stones.

But if you have the diamond plate, you had just as well flatten your working stones on it.

Yes, I bought one of those Norton "flattening" stones a while back so I'm relating my actual experiences with it.

I did keep it and use it as a very coarse stone for tools that are badly damaged. But for flattening working stones? No.

Mike

[Andrew Hughes]

Here’s the hot ticket.
A Shapton lapping disk. Then use the diamond plate to keep the flatness.
This is what it looks like.
Same principle as the Norton and one has to be careful not to dish out the softer stones. Like Mike mentions.

[Mike Henderson]

At the very least, Norton should tell people that the "flattening" stone has to be flattened occasionally in order to work properly. Too many people purchase it and then, after using it for a while, wonder why their working stones are not getting flat.

Mike

[Erich Weidner]

That Norton flattening stone has some serious problems. Your working stones tend to dish in the center so when you "flatten" them

Hmmm... well, that is disappointing. I do have the DMT plate, and used to use it, but after a few times where the higher grit stones became suction stuck to it I became a bit disenchanted. I love how quick the Norton thingie works, and never any sticky stones.

Now, I do tend to use a circular motion when I flatten with it, so maybe that is why I'm not seeing the convex edge you mentioned. (That or I've just not used it enough).

I guess I'll just have to remember to true it up every now and again on the DMT plate.

[Mike Henderson]

I do have the DMT plate, and used to use it, but after a few times where the higher grit stones became suction stuck to it I became a bit disenchanted. I love how quick the Norton thingie works, and never any sticky stones.

Try adding a small amount of dishwashing soap (such as Dawn) to your water when you flatten higher grit stones on the diamond plate. The soap won't hurt the stone and some people report that it eliminates or greatly reduces the sticking. Some people call it stiction.

Mike

[When you rub two surfaces together with a grit between them, the two surfaces conform. That does not mean they conform to two flat surfaces - it's much more likely that they conform to one convex and one concave. There's a process where you can use three surfaces in a certain order and get a flat surface. They teach machinist how to do it but I don't know the sequence. But if you're using only two surfaces, you'll most likely wind up with one convex and one concave.
For hand grinding small telescope mirrors (up to about 8 inches), the process is to use two pieces of glass with a grit between them. The top glass becomes concave and the bottom convex. The top glass is used for a mirror in a reflector telescope. Edmund Scientific used to sell kits to grind your own mirror for a telescope. Today, mirrors of that size are cheap so no one grinds their own any more.]

[Update: Well, it looks like they still sell those mirror making kits. See here for one example. I made a 6 inch mirror back in the 70's.]

[Vincent Tai]

That Norton stone flattener does the opposite of its job description. It cuts fast, and will take off your pencil grid and any marks on your water stones every time leaving the illusion that your stones are flat. Like Mike says, two surfaces conform, but not necessarily to two flat surfaces. I still kept mine for gross stone repairs for random very dished stones I find or shaping stones for other stuff. That lapping stone is what I would consider a diamond stone killer. Also a waste of time to try and flatten it with sandpaper; not to mention it's a waste of sandpaper. It also deposits it's own grit every time you use it, so you might as well be lapping your stones with coarse cheap sandpaper in the first place. I don't normally hate on products but I've detested this thing since I bought one 8 years ago.

[Jim Matthews]

So the DMT becomes the reference to keep the faster Norton flat? Straightedge to verify results?

This is how I use my coarse ATOMA, too.

[J. Greg Jones]

I too had one of those Norton flattening stones, and I was so disappointed in it for the reasons already mentioned that I threw it away. I would have been ashamed to have even given it away to someone.

[Robert Engel]

Even tho its a bit flawed, the Norton stone is a useful tool.

I use 80 grit on a flat surface a few strokes and your done.

I don't like using a diamond plate to flatten water stones for the reasons you mentioned.

[Doug Dawson]

That Norton flattening stone has some serious problems. Your working stones tend to dish in the center so when you "flatten" them on the Norton stone the Norton stone tends to become convex. To make the Norton stone work you have to keep flattening it. And to do that you need something like a diamond plate (I use the DMT diamond plates). If you don't flatten your Norton stone, you'll eventually be putting a concave surface on your working stones.

But if you have the diamond plate, you had just as well flatten your working stones on it.

Yes, I bought one of those Norton "flattening" stones a while back so I'm relating my actual experiences with it.

I did keep it and use it as a very coarse stone for tools that are badly damaged. But for flattening working stones? No.

I used to use diamond plates for flattening stones. Now I use one of these:

https://www.amazon.com/gp/product/B0...?ie=UTF8&psc=1

It's easier to clean, and it's cheaper to replace (the diamonds wear out.) I flatten in a circular motion under running water, until the pencil marks are removed. It helps to do it often. I check for flatness pretty regularly. If I ever noticed it going out of spec, I'd replace it, it's only twenty bucks or so. I haven't needed any more precision than that.

It's too hard to manhandle a surface plate into the sink to wash off the swarf thoroughly, I'm getting old.

[Tom M King]

I use Atoma 140, and 400 diamond grit replacement sheets stuck to a granite surface plate, but the dedicated sharpening sink has a plenty large enough drainboard, and a double swivel spout on one of the faucets so it can be used under running water (no such thing as water shortage here). I got tired of using things that weren't really flat.

[Eric Danstrom]

I bought one from Woodcraft, it went on sale 2 days later. I haven't used it yet but I threw away the box...now that I'm in it for $35 I could try keeping it flat with sandpaper on my granite surface plate. Except I could just use sandpaper/surface plate on my waterstones and skip the Norton brick...maybe I'll stash in the back of a drawer and forget about it.

[Mike Henderson]

I bought one from Woodcraft, it went on sale 2 days later. I haven't used it yet but I threw away the box...now that I'm in it for $35 I could try keeping it flat with sandpaper on my granite surface plate. Except I could just use sandpaper/surface plate on my waterstones and skip the Norton brick...maybe I'll stash in the back of a drawer and forget about it.

It works well as a very coarse stone when you want to take a lot off but don't want to go to your powered grinder because you might overheat the metal.

Mike

[Richard Jones]

sticky stones + diamond plate = mo' H2O. I'm fortunate that I have mine where the water can run continuously on the stones.