Brand new DMT 325 vs Brand New Naniwa 12k. Not a good combination?

Ok, so i just bought a brand new DMT 325 plate, and lapped up my 1k, 4k, and 8k norton stones, and they feel perfectly flat, definitely the smoothest Ive felt them (disclaimer, my honing ability is still pretty negligible, I've 'honed' about 4 razors, so the experience i have with these stones is still pretty small :P). So Ive read a few threads about a DMT 325 against a Naniwa 12k, some people said they had issues, some people said they had no issues. but I definitely had an issue. my DMT scratched the crap out of one corner, but worked well on the rest of the stone. Heres a picture.
Attachment 159619
So my questions is if i should try again, or try something else.
Just as a side note, I would just like to say that my previous lapping method was a granite stone, and a 600 grit sandpaper. On the 1k, 4k, and 8k, the DMT feels vastly superior!

Thanks!

UPDATE: I have discovered that this has been done this to all my stones in the exact same place, i just didnt notice at first, because the gouges weren't nearly as big the 1,4,8k nortons. So I'm pretty sure its the DMT?

Did you remember to "break-in" the DMT-325?

Quote:

---

Originally Posted by JBHoren

Did you remember to "break-in" the DMT-325?

---

I have read the 'users' manual and it says it might feels rough at first, and will 'soften' after use. I am not aware that there is an actual method to do this? Any help would be appreciated.

I took a steel bar and rubbed the heck out of my 325 DMT and you will feel a big difference. What it does is knock all the high diamonds off. You are not going to hurt the DMT trying it believe me :<0) All that said 325 may be a little ruff on your Nani . Go back to your old way on that stone.

When my 325 was new I used an edge (not the point but the shank I guess) of an older phillips screwdrive to 'burnish' it a bit. Not too heavy of pressure, and it worked pretty good.

Had to give my DMT 325 a couple of the razor shank treatments and now she is fine even for the 12K Naniwa.

Bob

The instructions are for using it as a knife sharpening hone.
I ran mine over the metal edge on the bed frame several times. Worked well.

That damage isn't about breaking in your DMT. It has a high spot. Judging by where the stone is scratched it could even be a high edge on the DMT. You might need to give the offending area a light tap.

Quote:

---

Originally Posted by onimaru55

That damage isn't about breaking in your DMT. It has a high spot. Judging by where the stone is scratched it could even be a high edge on the DMT. You might need to give the offending area a light tap.

---

I just updated the original post, but ill put it here to make sure everyone sees it. I just looked closer at all my stones I lapped, and noticed that the DMT gouged them in the exact same place like that, I just didn't notice it first because on the lower grits (1,4,8k) the 'scratches' arent nearly as deep.

Im not sure id be willing to 'tap' my DMT as to make it straighter. Firstly, if it is out, there will be no way to accurately guage if i get it perfectly straight, completely defeating the purpose of having the stone IMO :P, and with the plate being as thick as it is, I know I would need to hit it pretty hard. Should I email DMT about it? (assuming its not a break in issue).

I did use a shank of a screwdriver as everybody suggested, but it made the problem negligibly better. I have a steel bar in the garage I could possibly use...
Thanks for everybodies input!

I simply sharpened a crappy kitchen knife on mine until it lost the 'sparkle' and had an even grey tone to it.

For my 12k, i just flip the dmt over and wet-stick my 600 grit sand paper to it. Works great for me. Or you can do the same with the norton lapping stone.

USUALLY the plate itself is fairly flat. Onimaru is suggesting that it is not. Use a straight edge by holding it against the plate and looking for a gap when looking toward a light. If it is not flat, I'd send it back.

IF the plate is flat, then the breaking in is the issue. The diamonds are coated onto the flat surface but the highest point for some of them can be higher than the majority of them. These cause the apparent scratching until they are worn down to the level of most of the other diamonds. Rubbing steel on the plate speeds this up.

Given that no harm was done to your Nortons, I have no clue but here is a speculation:

When you lap, it is a good idea to occasionally rotate the stone or the hone (not both!) 180 degrees during the lapping. I'm assuming that you did not do this. If you repeat the lapping and rotate the hone, then if the other end of the hone is scratched, then I would assume the plate is at fault. If the other end is not scratched, then the hone may have a high end that looks worse because the plate was not broken in.

Quote:

---

Originally Posted by Xyphota

Im not sure id be willing to 'tap' my DMT as to make it straighter. Firstly, if it is out, there will be no way to accurately guage if i get it perfectly straight, completely defeating the purpose of having the stone IMO :P, and with the plate being as thick as it is, I know I would need to hit it pretty hard. Should I email DMT about it? (assuming its not a break in issue).

---

Sorry , did not make it clear. You possibly have a small high spot of diamonds near the end of the plate. If you can locate it & give it a tap you will break the dianmonds off as they will fracture. I use the corner of a spyderco ceramic hone to rub uspecific areas. Makes short work of it & can be used to break in the whole plate but in small doses only. The diamonds are quickly levelled.
If the plate itself has a high edge it needs to be returned for replacement.

If one of the corners is raised a few taps will do it,
they do however have solid customer service, if you call they will direct you.
that does look like more than a few high stones unless they all were bunched up in one spot?
which I guess could happen.....

Quote:

---

Originally Posted by pfries

If one of the corners is raised a few taps will do it,
they do however have solid customer service, if you call they will direct you.
that does look like more than a few high stones unless they all were bunched up in one spot?
which I guess could happen.....

---

Yes that can happen. A 2mm high spot will create such damage.

Quote:

---

Originally Posted by onimaru55

Yes that can happen. A 2mm high spot will create such damage.

---

I have not seen that personally yet, but it is great to know. Sometimes we approach thins like a rocket surgeon and miss the obvious.
Thanks OZ

Happened to me with a 400 grit Atoma.
Take a pencil & try to draw small figure 8's on paper & also rub it back & forward the same distance as when you lap. See the size of the pattern ? :)

Quote:

---

Originally Posted by pfries

If one of the corners is raised a few taps will do it,
they do however have solid customer service, if you call they will direct you.
that does look like more than a few high stones unless they all were bunched up in one spot?
which I guess could happen.....

---

+1 on this...
A clump of diamonds or a list of other problems could be the root cause.

I would note that if you are lapping a hone and you only see the problem
in one corner you are not lapping with figure 8s and not rotating the
lap over the hone.

Also note that you want to lap a minimum amount of water stone
away. Think one or two sheets of paper.

The occasional trenches you see do have value. I use them to keep
track of when I have used enough hone to need to lap it again. When
they are gone it is time to lap the hone again.

Also use a lot of running water as water stones are soft enough
that you can collect a layer that keeps the lap from giving the
entire water stone surface attention. One of the things I have seen
is scratches on corners with a smooth central region. i.e. I have
seen what you see and it was thick slurry mud getting in the way.

Always contact customer service ... your picture is all the evidence most
folk will need to understand.

What a dissapointment. Its things like this that drive me nuts. Your feeling good about your new gear and then this happens. Sorry man. I'd try to steel scrub the offending corner once more and see what happens. Then tap the high diamond area as onimaru55 recommends. If it failed, I'd call and ask for a replacement TODAY or I wouldn't be able to sleep. This makes me feel lucky my plate was in good order when I got it. Things like this happen to me when theres a 7 day weekend and the vendor is closed for a month.

Lapping is done faster, cheaper and better using wet/dry. I have the atomas and dmts also. The finished product is better as you have lots of choices for grits. I know you can get grit on your stones, but you can get diamonds on them from the diamond plates as well.

I would contact DMT or the vendor. I've had two DMT stones that weren't remotely flat and caused me endless frustration. Luckily one of them was so absurdly flat that I noticed pretty quick (I could put it upside down on a granite slab and slide a sheet of paper under the concave side, yikes!).