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After flattening a stone with a DMT Course or sandpaper, What is the highest grit you have gone up to after that?
The reason I am asking this question is my cousin was looking at my new coticule and said they have a lapper at work that would lap it and he stated it was 16,000 grit.
I am thinking about taking him up on his offer. Do you think a stone would benefit from this?
I have already used the DMT 325, DMT 1200, and then rubbed it well with slurry stone.
I now use the DMT 325 exclusively, with nothing after that. It doesn't seem problematic.
Lapping a coticule past something in the area of 600 grit is really pointless. The coticule's surface is constantly releasing particles into the slurry, essentially refreshing the surface constantly thus smoothing it. In other words, a coticule lapped with 600 grit will feel just as smooth as another comparable coticule lapped to something over 1200 grit.
As a note, you really shouldn't use the DMT 1200 to lap, it can be damaging to the higher grit diamond hones if I recall correctly.
Using a 1200 DMT may ruin the DMT, so I've heard.
1K sandpaper is my standard on manmade stones. On naturals, I typically will use a J-nat on a J-nat, a Thuri on a Thuri, coti on a coti, etc. No science behind this -- it's just what I do.
I also stick with the 325 but I do know some guys who go up to 1k grit sandpaper. Be careful using a DMT 1200 for lapping waterstones. The company says no diamond plate above 325 should be used as a lapping plate and I know of guys who wore the nickel binder off the 1200 plate using it on waterstones.
I watched Sham run his diamonds down the drain while lapping a Charnley.
Alright, I will leave it where it is. It sure is a nice stone and I most likely will not use the 1200 on another stone.
Thank you!
I lap naturals with other naturals. I use a worn off DMT 325 first.
I will most likely proceed in this manner for a while now. Rereading my post, I had to laugh, when I said slurry stone it was actually my 6 inch coti that I used on the 10 inch.Quote:
Originally Posted by mainaman
If I have scratches left over after my DMT325, I use a barber hone to get those out.
Leaving the grit concept aside. A commercial 16 k lapper might get your stone flatter than any other method we use.
Maybe a benefit , maybe not.
Realistically, it really doesn't matter. A 1000 grit lapped stone is not going to behave differently to a 325 grit lapped stone.
The scratches in the bonding agent don't abrade. Only the grit particles / garnets /... do. And they are fixed.
Lapping only influences the surface flatness to make sure the blade is flat on the hone. At the dimensions of a razor blade, scratch lines in the hone surface don't matter anything.
Lapping my CF was what turned my DMT from an aggressive cutter to a well worn in stone! :D It went from 325 grit to about 600 in that one session.Quote:
Originally Posted by nun2sharp
But yes, I use a 325 DMT for all my lapping and it works great. No need to go any higher than that IMHO.
Since acquiring a Chosera 1k and using it as a bevel setter, I have relegated my Norton 1k to being a lapping stone.
Jerry
____
I used to go to 1k, but when I bought the Shapton DGLP (325 Grit) and a Shapton 30k, I said "Huh 325 is recommended for a 30k stone" and that was it from then on... Now I use a DMT 525, that would also be known as a well worn DMT 325 :roflmao or the Shapton DGLP that's it....
325. Like Glen, I have a DGLP and a DMT 325. I have used both on stones up to Shapton 30K with no ill effects.
+1Quote:
Originally Posted by StraightRazorDave
I might note/ add that the initial slurry will finish the
process as the early hone strokes with a razor
worry the slurry and the hone surface to finer bits.
After this the dilution process will further remove the
aggressive slurry and leave the hone "just right".
Folk that tape might also consider that the
steel of the spine is part of this process. The
a'retentative folk might use that old razor with
a lot of hone wear for a half dozen strokes to
condition the hone surface. The old razor may become
your fav' shaver in the process. To one degree
or another this initial slurry interaction takes
place on any hone and with many a nagura/ rubbing
stone.
In my opinion, circles and Japanese strokes that
we see in video by the better hone masters when a razor
first touches the next hone optimize this process
Over time a DMT will calm down and this is less
an issue. You want a DMT that is coarse enough
to be durable and aggressive enough to remove
that half a sheet of paper bit of hone that is
needed to keep the hone flat enough over time.
The slurry is a key byproduct...
When I get my Shoubudani, I'd definitely going to use another natural (probably a coticule) followed by a tomonagura to get it as smooth as possible, but for synthetics or even coticules, I've found no benefit to going beyond my well worn DMT 325. :) The real Jnat experts on here have explained why you want smoother on level 5 stones, but yeah, for most other stones, probably more would be overkill.
:roflmao I think I am around DMT 425Quote:
Originally Posted by gssixgun
I just finished this as seen in this thread( Chinese 12k dressing stone) and it works quit well. I believe it just may take away that first razor smoothing effect or take the place of. It definitely smooths out the roughness left from the DMT.Quote:
Originally Posted by niftyshaving
A new 10" Coticule? Nice. I don't see no reason to not try out the 16k lapper once :D I would bring a very dished Hard Arkansas along though.Quote:
Originally Posted by Grump
As others have said if you're going to make slurry on the stone you don't need much of a finish, just make sure it's flat. Making slurry will smooth the surface.
The more I think about this opportunity to lap the stones on the commercial 16k lapper, the more I am thinking about just trying it out for experimentation sake.
I also realize that each hone has its own qualities and is going to react in a such a fashion. I can see that being true with lower grits especially but when you get into higher grits and naturals, how much does lapping and polishing of the stone play into its qualities?
Give it a try and let us know how it works.....not that I'm going to go out and get a commercial lapping machine, but it would still be interesting.Quote:
Originally Posted by Grump
Quote:
Originally Posted by Grump
I would too :) Any chance to expand knowledge to our hobby should be tried if we get an opportunity....
I would love to try it on My Arkansas and my Charnley Forest
I would agree except for with arkansas stones, where the "binder" is also the abrasive.Quote:
Originally Posted by Bruno
I lap all my stones with a 220 dmt lapping plate (not the sharpening plate).
For my higher grit stones i then use sandpaper to remove the scratches left from the DMT. Depending on the stone depends on how high i go. On my Chinese 12k i got to a 400 then to an 800 to give it a glass like feel and i have even tried a 1k (i was told by a few members to get the C12k as polished as much as i can for the best results)
I have both sides of my C12k lapped and the second side i leave with the 220, Both sides feel quite different to sharpen with. The 220 side has a 'zing' sound when using it (if that makes sence) and the polished side has next to no sound when using it. I find the marks in my C12k from my 220 don't disappear but it hold a slurry well and creats a slurry a lot faster then the polished side, i can then transfer some of that slurry across when i flip it. :D
My shapton 8k and 16k i finish at 600
and most my other stone i finish with a 400 or the 220dmt
I will occasional finish my other 12k stones with a 600 but, at the same time, sometimes the 220 gives it a nice feel different to what the 600 gives.
I have been playing with some new jnats and i have been finishing them with a 1k and even tried 1.5k - i 'think' the 1.5k made a slight difference but not enough to make it worth while. I really should ask one of the pros whats best for lapping the jnats lol but they are supper hard and any marks or scratching takes a long time to disappear!
Still playing and still learning with all my stones. Maybe i will learn something from this thread :D
Edit: This jnat stone i lapped from a 40 grit lol but it was in really bad condition. I first started with the 220 DMT and when i realised that wasn't working i put in on my belt sander. That didn't do anything so i purchased some 40, 80, 160 grit and so on - Took me 6 hours to get it flat (minus a break here and there and a drive to burnings for some more sandpaper).
But if i had have started with a 40 grit in the first place i think it would have been a 2 hr lap and not a 6 hr lap lol
I find SiC powders on float glass considerably faster. It may be there is no cushioning from the sandpaper but I can't imagine spending 6 hours, even on a hard stone.Quote:
Originally Posted by Brighty83
+1Quote:
Originally Posted by TheZ
One trick with Arkies is something like fine (8K) loose grit
or even a light spritz of 2micron diamond. Because an
Arkie is so hard it need not be lapped often... but it holds
the feel of the lap for a while without finishing. Same
is true of the Spiderco ceramic hones.
Its sorta relaxing, once i started to see results. lol. Its not something i would want to do too often.Quote:
Originally Posted by onimaru55
I have done a google for SiC (silicon carbide powder) powders on float glass but i cant find much. The lowest grit i could find was 120. Do you have a site you recommend of the powders and the glass?
Glass -- a local glass shop.Quote:
Originally Posted by Brighty83
My grit -- hunt a local astronomy club.
Gem polishing sites are what you wantQuote:
Originally Posted by Brighty83
Tumbling Grit and Abrasives
Gemcuts Lapidary Supplies - Lapidary & Jewellery Equipment for the Professional or Hobbyist
Shapton sells abrasive powders for use with their cast iron lapping plate. I don't know what the material is and, frankly, I'm too lazy to look it up :-). Check their site, I would assume that Shapton has given some thought to what would work well as a lapping compound.Quote:
Originally Posted by Brighty83