Thread: Lapping. Any reason I shouldn't do the following?

Hey guys,

I normally lap my stones before and after a hone session.

Normally, I lap with 400 or 600 wet/dry on a marble in a sink or tub or whatever. I never apply a heavy amount of force while lapping.

I've been thinking, is there any reason why I shouldn't be lapping with a high grit, something like 1500, 2000, or 2500 that I have on hand?

Or, lap the 12K with the 8K or 3K??

I'm thinking for the following stones Naniwa 3K/8K/12K.

Any thoughts on the matter?

Will I be reducing the cutting power on the 3K/8K by doing this(by more finely polishing), thus, taking longer to hone at these respective levels?

Should the above approach maybe done for a finishing stone only??

If your stones are lapped properly after a honing session, there is no reason to lap them prior to the next one.

Personally I believe smooth is way more important than dead flat.

Once lapped flat, a quick lap with a Diamond plate, 320 or 600 mostly to remove any swarf is all you need. Heck a scotch brite will work almost as well.

With synthetic stones the lapping grit really does not matter, as the stones are friable. A diamond plate is just easier and quicker than wet and dry and they are not that expensive and will almost last a lifetime.

Originally Posted by Euclid440

With synthetic stones the lapping grit really does not matter, as the stones are friable.

If this is the case, then why is it recommended to lap my synthetic barber hone with a particular method here: How to lap a Barber hone.

I'm not trying to be difficult or argumentative, just interested in getting the best performance out of my stones possible. I admit I know so little, so I lean on the heavy lifting of other.

With that being said, I'm half contemplating lapping my Apart barber hone with the Nani 3K, then 8K, then 12K. Heck, I already took it from 180-220-400-600-1000-2000-2500 grit. I'm sticking to only lapping one side so I can compare it against the other side.

I'll probably do the same with the 2 Line swaty once the vasoline finishes sinking in.

kind regards,

Simon

I have a 3-line Swaty, still in the box with the instructions, and it just says lay the razor flat and do 10-12 laps, nothing about Vaseline or lapping it...supposed to be a dry hone I believe...just what the instructions say on mine and it works.....

edit: just checked, say's it can be used dry, with lather or oil. It say's after long usage, it can be washed with soap or sanded with a fine grit sandpaper to ensure a clean surface.

I only lap after honing maybe three or four razors depending on need. When swarf buildup is quite obvious or when I notice cutting speed has been slowed considerably it is time to do something. Many times I will rub together similar grits. say a 1 and 4, 4 and a 5, or 5 and 8, 8 and 12 thousand grits.
With waterstones, a thourough wash with wet fingers and a good rinse completes the task
This works well enough and restores the efficiency of cut.
Sometimes I break out the 325 diamond when there is a hump in the middle of a hone. Every once and awhile I break out the granite slab and use it with a320 or 400 grit wet paper just to restore a very flat surface, but only when needed.
I really can't think of any reason to resurface/lap any hone both prior to use and after use.
I would think higher grit wet paper would only slow down the process.
You have a nice set of Naniwa hones and I hope they are serving you well.

Concerning the barber hone I would only lap it if it needs it,
Is it glazed over or does it have other surface problems?
Many times barber hones were abused by someone with a knife. Being used to a much coeaser hone, when the barber hone would not cut as fast as normal, many times they put a lot of pressure on it and forced bits of steel to lodge between grains in the hone which is what I call a glazed over hone.
The barber hones are much, much harder than waterstones (possibly ceramic) and if you use waterstones to lap the barber hone you will likely cause damage to, or at least cause a lot of wear and tear to some pretty expensive hones.
If the barber hone really needs lapping I would give it a try with some 220 grit wet paper and a flat surface of some kind.
Expect to wear the entire sheet into pieces and have the barber hone escape barely changed at all.

Once you lap it flat the first time, honing a razor or two is not going to dish the hone out.

The barber hone probably suffered more from improper storage (drying and warping) that over use. There is no way someone could have worn out the middle of the barber hone, finish honing a razor.

A barber hone is completely different from a synthetic friable hone like a Norton or Naniwa. If it’s not perfectly flat the razor will ride over the low spots, but that would take a lot of razors or abuse.

Mostly what you are doing by re-lapping is removing any glaze or swarf. Finer grits will not make a difference on a friable stone.

As Modine said in that thread “Once the hone is flat you can proceed to polish the surface with finer and finer grits. However the surface texture will not improve the performance of the hone much past the DMT Extra coarse plate.”

Originally Posted by Euclid440

Personally I believe smooth is way more important than dead flat.

Once lapped flat, a quick lap with a Diamond plate, 320 or 600 mostly to remove any swarf is all you need. Heck a scotch brite will work almost as well.

With synthetic stones the lapping grit really does not matter, as the stones are friable. A diamond plate is just easier and quicker than wet and dry and they are not that expensive and will almost last a lifetime.

I would caution using Scotch Brite on synthetic stones. You replace the swarf with particles from the Scotch Brite pad. I know because I tried this and it does. Naniwas for example are just too "soft" for such a cleaning method.

Frank