Thread: it's time to get serious about learning honing. One last question for the pros:

Lapping theory could be complicated if you made it, but the basics are not. You can easily lap a coticle and both sides of the norton with sandpaper and a glass table (or other surface that is perfectly flat). There are plenty of videos out there to watch to get the basic ideas down. Watch the videos and just take your time.

The one key thing to note, IMHO, would be a crucial step that I missed for awhile. Round the edges of the hone down as, or after, you lap the face of the stone. I found that not rounding the edges and corners off left a sharp edge on the hone and this equaled micro nicks in my razors.

If you are practicing technique you can get away with not lapping but if you want to take any serious crack at making a razor "shave ready", it is best practice to lap your hones.

Also, I never really researched what grit sandpaper people recommend but i typically go with 220-600 grit depending on the grit of the hone. maybe someone with more exp. can chime in about that.

Comparing grits of sandpaper with lapping plates, the Shapton GDLP is rated at 325 IIRC and the DMTC is also 325. Many guys, including me, use those with good results. The DMT X and XX are also recomended by DMT for lapping water stones and are coarser. I don't remeber exactly what the grit ratings are. The thing about a plate versus paper is that the plate will last many moons and the paper can add up over time. Also it is nice to lap right in the sink with a plate letting the water trickle down and wash away the swarf as you lap.

I usually use my DMT 325, but have used 225 wet/dry quite a few times and still use it sometimes on stubborn barber hones.

Originally Posted by JimmyHAD

Comparing grits of sandpaper with lapping plates, the Shapton GDLP is rated at 325 IIRC and the DMTC is also 325. Many guys, including me, use those with good results. The DMT X and XX are also recomended by DMT for lapping water stones and are coarser. I don't remeber exactly what the grit ratings are. The thing about a plate versus paper is that the plate will last many moons and the paper can add up over time. Also it is nice to lap right in the sink with a plate letting the water trickle down and wash away the swarf as you lap.

Lapping is much easier than honing. Go to Lowe's or Home Depot and go back to the tile/flooring section. Tell the guy you want the cheapest 1'x1' marble tile they have. All you need is 1. Should be like $3.

Then follow the directions here: Hone Lapping 101 - Straight Razor Place Wiki

All you're doing is "sanding" the stone down flat, aka lapping.

The grid you draw doesn't have to be precise. It's just there to make sure you get all the areas and don't have highs/lows.

With the Norton Stones, you wanna let them soak before you do the lapping. Coticule, you don't have to.

You can use sandpaper, but if you plan on honing any amount, get a DMT D8C hone. Will save you money on sandpaper. Also, as mentioned above, make sure you round the edges. They WILL mess up your edge.

Originally Posted by Lynn

Actually the 4K side of the newer Nortons are pretty granular and should be lapped down about 1/8 inch until the grainey feeling is gone. They perform a ton better that way. I would say no problem on using the 8K or the Coticule as they are.

I got my Norton yesterday & the 8k still had a grainy factory finish, but it lapped off to nice & smooth in under 5 min on a DMT 8C. Maybe they vary a bit? Not sure as it's my 1st one, not my 50th. I'll let the Norton expert answer that one. The 4k side did take close to an hour on the DMT. (Obviously I did it in stages so my arm didn't fall off!)

If your coticule feels smooth to the touch when you get it, you should be good to go. Some of the stones the old barbers used were noticeably dished & worked fine. Mine felt a bit "ribbed", presumably from grinding @ the quarry. Not even sure it was necessary, but 2 min on the DMT had it perfect.

I don't know if lapping is strictly necessary, but I do know that after you get used to lapped stones, it's difficult to tolerate one even a tiny bit dished. The standard changes.

I've got cheap synthetic aluminum oxide stones that I use on my coarser waterstones when cleaning up, scrubbing them off and lapping all at once, and a steel plate DMT8000 that I use on coticules and japanese stones.

I just use a little water/detergent mix on the DMT (in a heavy stone holder), and use the polishing stone in the same way you'ld use a nagura, stopping when there's a good slurry accumulated. It actually removes very little, and done regularly is sufficient. There are no deeper scratches abraded as would be so with coarse diamond hones, and the slurry left behind gets treated like it belongs there.