Thread: Rough lap

I'm new at this, of course, and I lapped a new 4/8 Norton and Chinese 12 with the Norton lapping stone until the pencil grid was erased. The 4 and 8 seem to be rougher and the 12 is deciidedly rougher than the unlapped side. Is this what I shoould expect?

that doesn't happen to me. maybe you lapped with something too course, or maybe you are just feeling the slurry? after i lap and rinse, the surface is smooth, on my 1k and 8k norton. i've never lapped a 12k chinese

Regarding slurry, did you lap under running water? That is a must.

Yes, i did it continously under running water.

So that should remove any slurry...

Perhaps the stones were clogged when you first got them; my understanding is that lapping will unclog stones in addition to flattening them.

I guess I should clarify a little more. The 12k is definetly flat and it is not rough like sandpaper, but the unlapped side feels much slicker. I guess my question is should the lapped side feel the same as the unlapped?

I think it is normal for the slickness to go away. That has happened with the various barber hones I have lapped. I believe it is ofter referred to as "opening the stone up," and is what I was referring to above.

Opening the stone up sounds like a good discription to me.

Thanks

The Norton lapping stone is a coarse grit. That will leave a coarse texture on the 4/8 and 12K. To smooth out the texture on the hones you need to lap them again with a finer grit such as sandpaper under running water and rinse the stone when done. You could also lap the Norton with the 12K but I prefer to use 1000 grit wet/dry sandpaper. Whichever you decide to use be sure to rinse and scrub the stone with a nylon type pad when finished. That will remove any embedded grit.


Hope this helps,

I've never lapped a waterstone but I've lapped several NOS barber hones. When new, they have a slick, glazed surface that doesn't really remove any steel. After lapping, there's much more frictional drag when I draw the blade across. This has happened with every hone I've ever lapped. So I'm pretty sure this is normal, & furthermore you HAVE to remove the glaze for the hone to be effective.