Thread: Suehiro Gokomyu 20K Waterstone

Originally Posted by UKRob

I'd appreciate some advice - I've been using the Suehiro Gokumyu 20k stone for a few months now after a progression (where require) of 1k, 3k, 5k and 10k Naniwa stones. I get a mirror polish from the 10k which then goes a little backwards i.e. slightly more noticeable scratches after the Gokumyu. I use a slurry on all stones in the progression except the Gokumyu and I keep it clean with the double sided stone provided.

Has anyone else come across this before?

I have not lapped the stone as I read on the forum that it wasn't needed - but I'm now wondering whether I should try this anyway. Thoughts appreciated.

I think you will find that you DO need to lap it. I know I lapped mine. Greater scratch patterns and going backward is definitely NOT something I've experienced with the G20. Quite the opposite. The only thing I can think of is that its not flat. Flattening it is a job but it needs to be done. Also, the "slurry stone" that it came with is great to use after lapping to finish the surface off. You should not be moving backward with this stone.

Hi Rob
I use the same progression as you. With every new razor I shave off the 10k and if alls good I do 20 strokes on the gokumyo and I know I can get an outstanding shave. I had a 10k shave with a new heli which was very good with a mirror polish. I've just finished my 20 laps and looked again with a 40k loupe. It was noticeably better but not by a huge amount. I can only suggest that your gokumyo needs lapping. Its a very hard stone and takes a while but I'd say the results would be worth it.

I just got a Gokumyo 20k for Christmas. It was pretty flat, I gridded and lapped it with a new, I Wood 300 diamond plate. Nice plate by the way with cut diagonal grid on the plate, no stickion…

It lapped quickly twice and did a quick lapping with a worn 600 DMT. It was pretty flat and very hard.
I have finished 5 razors on it, after a 12k Super Stone with Glenn’s 3-2-1 method. 3 edge forward, 2 spine forward, 1 edge forward, weight of blade.

Shaved off the stone nice and 20 laps on .125 CBN both smooth shaves.

It is very similar to a .3 lapping film with paper edge, post a 12k Super Stone. I do 5-6 laps on .3 just to finish the edge, very similar edge without the hassle of the film.

Worth it? Yea I think so, especially if you hone a lot, if not then .3 film will get you close to this edge for a lot less cash.

Bob you do not need anything between the 10 and 20k. I fininshed on a 10K Ice bear, for many years until I bought 12 K Super Stone years ago. The finish is very similar between the two, the super stone is a bit harder.

You can go from the 10 or 12k to the 20 easily. Try stropping lightly on Chrome Ox, then the 20k finishing laps for a nice edge.

Originally Posted by mainaman

How is the shave between 10k and 20k? If there is improvement in the edge quality then may be the scratches from lower grits were not completely removed.
I personally lap my 20k from time to time, I just make sure the surface is smoothed further than the lapping stone (well used DMT 320). I use coticule slurry stone for that last step.

Well, I have not tried the shave after 10k - just after the 20k and it's good. I just did not understand why the scratch pattern gets marginally worse.

Originally Posted by OCDshaver

I think you will find that you DO need to lap it. I know I lapped mine. Greater scratch patterns and going backward is definitely NOT something I've experienced with the G20. Quite the opposite. The only thing I can think of is that its not flat. Flattening it is a job but it needs to be done. Also, the "slurry stone" that it came with is great to use after lapping to finish the surface off. You should not be moving backward with this stone.

I will lap it and then finish with the stone that comes with it as suggested. The other thing I forgot to mention is that I've been using the bottom of the stone - I don't suppose that makes any difference but you never know.

Thanks for the responses anyway.

I've read on other posts that some are not getting the same results using the bottom side.

Originally Posted by markbignosekelly

I've read on other posts that some are not getting the same results using the bottom side.

I do not see how a stone made in batches will have two different in properties sides. I lapped both sides on mine and got the same results.

Originally Posted by UKRob

Well, I have not tried the shave after 10k - just after the 20k and it's good. I just did not understand why the scratch pattern gets marginally worse.



I will lap it and then finish with the stone that comes with it as suggested. The other thing I forgot to mention is that I've been using the bottom of the stone - I don't suppose that makes any difference but you never know.

Thanks for the responses anyway.

Keep in mind that little "slurry stone" (not really a slurry stone at all) that comes with it is for cleaning the surface between uses. Once lapped, you can continue to use that little stone to ensure the surface is prepped and ready for the next use.

Why are you using the bottom, (the side with the printing)?

How many laps and are you using weight of the blade pressure?

Same complaints with .3 film when too many laps or too much pressure is used.

Originally Posted by Euclid440

Why are you using the bottom, (the side with the printing)?

How many laps and are you using weight of the blade pressure?

Same complaints with .3 film when too many laps or too much pressure is used.

I use the bottom side because the top side was way convexed & too difficult to lap flat. It works just fine.

For the op. Scratches are obvious in high polished bevels. Even the strop can mark such bevels. If they are deep & end in a glint at the edge if held at the right angle in the right light they are from a coarser stone. You may need a loupe to see this.

I was honing a custom razor and my two SRP razors (Robert Williams) and while honing on 1 & 2K I like to do a few laps on a high grit stone before looking at a bevel during bevel set. I am truly AMAZED at how much material can be removed with 10 x strokes. There were very little 1K scratch marks left when using the 20K (my normal routine is Chosera 1K, SHapton 2,4,8,16K, & Escher, but my 16K was in the bathroom for barber hone detail so I used the G20). I haven't heard of many over-honing issues with the G20 & I am surprised after that result. You guys should try looking at your scratch marks after each stone & then take the razor to the 20K for a few passes. You can easily go from 8K to 20K no problem at all! I still finished with Escher, but that's my preference.

Scorpius: Choosing the G20 was a wise choice over the Shapton 30K IME, I personally don't see much use for the 30K with razors & sold mine quite a while ago.