Thread: To Lap a New Hone...

Does everyone know that you need to lap/flatten a new hone right out of the box before use?

I've read a lot on razor forums where people use stones right out of the box without lapping them first. I've seen it in pictures and noted many making comments about this. I also know from talking to my customers and knife sharpeners that they too do this as well. It seems like this bit of information has been lost or never known, I can't say which but that doesn't matter.

The fact is that a Japanese synthetic waterstone comes with a sort of surface crust that needs to be broken through and lapped away. Not to mention that many aren't flat and lots have ink and even stickers on the surface that need to be dealt with. If you don't break through the surface of some stones they actually won't work almost at all. I've seen it countless times where a sharpener buys a new set of pricey stones just to be left scratching his head after the first use pondering how these things could be so highly regarded when he can't get them to do anything decent for him. He then thinks that either the stones suck, the people who gave the advice on the stones are idiots, or he doesn't know what he's doing -all very frustrating things to deal with.

I have found that there are some exceptions to this rule but they're few and far between so when you get a hone lap it and all will be good.

Remember, I'm talking about Japanese synthetics, not naturals or any other nation's sharpening stones, they may well all be different in this sense.

Dave

I respectfully disagree. I recently bought Naniwa 5 and 8k hones. I used both right out of the box, without lapping, and honed up a batch of 16 razors. They all came out great. Lapping out of the box, though probably a good idea, is not necessarily necessary. As with all things, there must be a percentage of hones that are flat or close enough to flat to use straight away, and others that are not.

I always lap a new hone regardless of origin. I feel better doing that and in the scheme of things it is doing no harm and maybe a lot of good.

I lapped my Shaptons right out of the box using the grid pattern. I had read it was a good idea to do so, so thats what I did...!

Now I only lap them to clean off the swarf, or if I have done a lot of honing and I want to ensure that the stone is flat.

Place a ruler on the 2 diagonals of the hone and use some light, if the light passes to the other side it needs to be lapped. (make sure the ruler is straight, I know for experience not all are )

I used my naniwa 8k out of the box with no problem, the 5k needed lapping

Originally Posted by DaveMartell

Does everyone know that you need to lap/flatten a new hone right out of the box before use?

I've read a lot on razor forums where people use stones right out of the box without lapping them first. I've seen it in pictures and noted many making comments about this.

really? this is all news to me. can you point out the pictures which show unlapped hones? for as far as i remember lapping the hones has been considered standard and necessary practice on this forum. as a matter of fact josh earl made a photo tutorial a year or two back of lapping with sandpaper (the cheap version) and it's been part of the wiki for a long time now.

for example lynn has repeatedly posted that the current production nortons require some good lapping to go past the more grainy top surface.
when i just bought my naniwas last year glen told me to give the 1000 good lapping several times leaving it to dry in between, it certainly started working properly after that.

My Naniwas SS are combination stones, they came without any sticker on them and without any residual glue. They were bought as new and looked like it, they weren't lapped when I got them.

Originally Posted by gugi

really? this is all news to me. can you point out the pictures which show unlapped hones? for as far as i remember lapping the hones has been considered standard and necessary practice on this forum. as a matter of fact josh earl made a photo tutorial a year or two back of lapping with sandpaper (the cheap version) and it's been part of the wiki for a long time now.

for example lynn has repeatedly posted that the current production nortons require some good lapping to go past the more grainy top surface.
when i just bought my naniwas last year glen told me to give the 1000 good lapping several times leaving it to dry in between, it certainly started working properly after that.

I don't have to search far for this, there's guys right in this very thread who have admitted to it - the OTB Naniwa guys. Just because people have delivered the message over and over doesn't mean the point has been made. I myself talk about this on Knifeforums util I'm blue in the face yet upon posting this very same topic over there we have a bunch of people admitting that they never heard it before.