Thread: norton 4000 resistance

Originally Posted by JoshEarl

In addition to the usual advice to draw a pencil grid and lap until it's gone, I think we should also advise newbies to lap until the factory surface is gone. I'd say give the hone five to 10 minutes on a 220-grit paper, then finish for a minute or two on 600-grit paper.

Josh

I never knew that there was a "Factory surface" that needs to be removed. I will need to give this info a try. I notice on my 4k side that there are spots that seem different... more course than the rest of the surface. Perhaps this is the problem. Seems to make sense.

How thick is this factory surface anyway?

I have flattened my hone on 400 and 800 grit wet/dry but only enough to get it flat.

Just when you think you know what there is to know...

How can you tell if the surface is removed or not? Will using the flattening stone in the future provide decent lapping?

I must thank Josh for all of his helping hands lately.
Thanks!

Good call Josh! and very nice of you to make the effort.

When the man made stones are made at the factory they are placed in a high pressure mold and then fired at high temps for a long time. This does result in a slight surface "glazing" hat can impede the performance of the hone. Josh has it right, lap with coarse grit first but finish with a finer grit like 600-1000.

Matt,

The factory surface isn't very deep. I think most guys are worried about ruining their expensive hone and so they lap really gingerly at first. Short of dropping and shattering your Norton, or gouging it deeply, it's hard to really ruin these hones. You might have to do some extra lapping to fix it, but since the hones will last for thousands of razors, wasting a little bit of it really isn't going to kill you.

The Norton flattening stone will do a great job of maintaining the surface now. Actually, it would have been fine to take off the factory finish, too. But we didn't know that was the problem.

It's hard for a new honer to tell if the factory finish has been removed, since you wouldn't have any baseline to know how the hone should feel. Spending a little extra time on the initial lapping is good, and feel how the stone's surface changes as you progress.

Josh