Thread: Norton's shredding my edge...

Well, I broke down and got a three-inch Norton 4/8k, which is a beast compared with the Japanese waterstones I'd been trying to learn with.

It seems like my technique on the 4k side is OK. I'm using X-strokes with light pressure, and when I look at the edge under 60x magnification, it's straight and the scratch pattern look uniform.

Then I go to the 8k side. When I start the X-patterns I can feel the edge catch on little pieces of grit or something. After about 20 laps like this, the edge looks a lot worse, with many, many little micro chips. (I'm not doing pyramids at this point because I have to use a lot of laps on the 4k side to fix the chips the 8k side is creating.)

I've lapped the stone on 400 and 2000 grit sandpaper. I also made sure I'm using it on a lint-free surface, after theorizing that the stone was picking up dirt from the terrycloth towel I was putting it on.

What's going on here? I feel like I'm making progress, except for this problem.

Thanks for any help you can offer.

Josh

Have you made sure that you're not carrying grit from the 4k side to the 8k side?

I'm not sure, but it sounds as if you have picked up grit from your lapping sandpaper. A glass plate with lapping grit, or a Shapton, is preferred, but not required. Try using a scotchbrite pad under running water to clean (not lap) the stone. Then use your palm under running water to sweep it a few more times. That might take care of the problem.

Do you see any little black spots on the 8k side?

Did you use ordinary dry sandpaper and not the required wet/dry sandpaper?

I did use wet-dry sandpaper to do the lapping.

Randy, there are some irregularities--they look like they might be tiny pinholes--in the 8000 grit surface. But when I run my hand over the surface when it's wet, I don't feel anything. And the gritty-ness doesn't happen every time in the same spot.

I tried re-lapping the stone, on 800 grit paper this time. Then I let it dry, and when it was dry I did a few laps with the blade. The gritty feeling was still there, although I noticed the blade had a few tiny yellow shavings on it. After a couple of dozen dry laps, the gritty feeling wasn't as pronounced. Maybe there's something there that the lapping isn't getting rid of.

After that, it seemed a little better. It's still not silky smooth, though. Maybe I'm just breaking it in.

Thanks for your help,
Josh

One thing: don't use your Norton dry...ever. Always have water on it. You don't have to soak the 8k, but use a splash of water on the honing surface.

i had the same problem and after reading a thread here about how the stone picks up grit from the sandpaper i realized that's what had happened. i'd been using the norton without lapping it and the stone was sharpening nicely, but then i used the stone to sharpen a kitchen knife and created irregularities on the surface. after i lapped it i noticed exactly what you are talking about. you just have to get the grit out. keep running it under water and rubbing it with your hand using a lot of pressure until you can no longer feel those little particles with your hand. be patient; it took me hours. the scotch brite pad sounds like it would work, too.

Under running water, using the nylon scotchbrite pad, rub that hone until the particles are gone. Then let us know how it is.
That hone has to have a uniform surface texture to use it for Str8's.

I think I've fixed the problem. I ended up just getting more sandpaper and lapping the heck out of the stone for a while. It seemed like there were little tiny pockets, almost like what an air bubble would leave, on the surface.

Also, some of the gritty feeling was coming from the edge of the stone, which seems a bit uneven. If the edge of the stone comes into contact with the shoulder of the blade, near the shank, it feels rough.

But now the flat working surface is smooth. I'm not quite passing the hanging hair test yet, but most parts of the blade will snap a hair dragged across it.

Thanks for all the help.