Did I break my DMT 1200 while trying to break it in?

[FaPat5]

I've got a DMT D8E 1.2k which I wanted to use for bevel setting (copied from seraphim's synthetic progression).

I tried breaking it in by running the back of some scissors, a barber hone (just for a brief while) and some crappy razors across it. It seemed to work because I managed to get one of my razors done quite well on it.

Anyways, after I did some honing, I thought maybe I should run a chisel across it for good measure? Bad idea - now my dmt is full of scratches :-(

Have I screwed it up or is this normal? I can't see how a stone like this which is used for chisels and knives and stuff could be damaged by a crappy old chisel? Do they get scratched like that often?

 

[Mike H]

Pics would help. Did the corners of the chisel dig into the plate?

 

[Doc226]

Pics would help. Did the corners of the chisel dig into the plate?

That was my thought as well, there should not be any gouges on the surface

 

[FaPat5]

Yes sorry I can't do a picture at moment because its a bit late but ill make one. It's just scratching everywhere. I mean there were scratches on it even from the razors - tiny ones, so that's why I'm not sure.

I'll try to get some pictures.

As for the corners, I don't think so, I kept it flat.

 

[Gamma]

It may be fine - my DMTS are full of marks.

 

[professorchaos]

As long as you didn't dislodge any diamonds - ie it isn't cutting anymore - you should be fine.

 

[SliceOfLife]

I've got a DMT D8E 1.2k which I wanted to use for bevel setting (copied from seraphim's synthetic progression).

I tried breaking it in by running the back of some scissors, a barber hone (just for a brief while) and some crappy razors across it. It seemed to work because I managed to get one of my razors done quite well on it.

Anyways, after I did some honing, I thought maybe I should run a chisel across it for good measure? Bad idea - now my dmt is full of scratches :-(

Have I screwed it up or is this normal? I can't see how a stone like this which is used for chisels and knives and stuff could be damaged by a crappy old chisel? Do they get scratched like that often?

Full of scratches?

Did you wash it? Could just be trails of metal filings in the diamonds if you were running the edge/corner of the chisel on it (would leave a trail that looks kinda like a scratch). Or you could be honing on the back side of it (no diamonds, just steel). I don't have a continuous E (just EE) and I know myself and a LOT of others had trouble telling which way was up on their EE's on arrival (basically had to use it and see if I got swarf to figure out which way was up).

I've been using my EE for years and there are some VERY light scratches (diamond came loose and cut a path between other diamonds) on the top side, but they are few, far between and barely noticeable unless you really look close. The bottom however is heavily scratched up.


But yeah, pictures would help.

 

[FaPat5]

Don't worry, I'm definitely using the right side (there's an arrow on the side and I can pretty much guarantee I'm using the right side). I'll get pictures up for it after work today. I might try cleaning it with a scouring pad or something, but I'm just scared in case its damaged, because they're obviously not cheap. Thanks for all the help so far guys!

 

[FaPat5]

Pictures as promised. I hasten to add that the grey crap in the middle is from my barber hone (I didn't lap it completely because I got too nervous about damaging the diamonds). I'm sure that'll clean off. The scratches are fairly clear but good news is that they are not really deep and you can't feel them if rubbing your hand over the hone.

 

[FaPat5]

Damn, sorry some of them are the wrong way round. Phone uploaded them funny.

 

[SliceOfLife]

Hmm, again I can only compare to my EE, those do appear to be scratches from diamonds freeing and cutting paths, but that's a LOT of them in my opinion.

Maybe someone with a continuous E can weigh in. But my EE has by my count a total of SIX scratches that would compare to the ones covering your plate. If it still cuts fine, I'd use it a few more times and keep an eye out for any new scratches. If it continues to get more scratches, I'd consider returning it, since it could be an issue with the diamonds not being adhered sufficiently well. But as long as the scratches stop appearing (IE it stops shedding diamonds), it should be fine.

edit upon reading that you're lapping on this plate:
But also, you shouldn't lap on an E. Some people swear it's fine, others have had theirs destroyed by doing it. The manufacturer says don't lap hones with anything above a C, and I believe they'd know best there. It's entirely possible that the hone lapping is what freed all those diamonds, assuming the chronology checks out there. And you wont damage the diamonds... they are as hard as diamonds. What happens is you create so much surface friction (since the hone seals against the plate so closely) that the diamonds are ripped right out of the substrate (nickel I think they're set in?)), which is exactly what appears to be happening to your plate.

 

[FaPat5]

Yeah, that's why I stopped the lapping after just a little (just rubbed across a few times under water) because I was scared of damaging it. I'm not aiming to use it for lapping again, just thought initially it could help to break it in, but like I say I didn't go all the way through with it.

Based on how the surface looks up close, I think the patch should clean off and that patch does still cut fine so I'm hopeful I haven't screwed it up. I will say that the scratching didn't follow the lapping, only much later use of the chisel.

I hasten to add, there were always loads and loads of tiny scratches on it right from first use (I always used water and soap/dishwash) but these after the chisel are bigger than the rest.

I did see a comment somewhere that people do get tiny scratching, but I've never used on, so that's why I'm not sure.

 

[SliceOfLife]

Here's my EE. You can make out a couple of the scratches, but as you can see, nothing like yours. I'd definitely not lap with it again if I were you, but as long as it stops shedding diamonds and it still cuts fine, then it should be ok.

 

[rajagra]

A lot of 'scratches' will disappear if you clean the plate with a nail brush.

You can ruin these by lapping hones. If a slurry builds up you can remove the diamonds from the nickel layer that holds them.
I did some harm to my DMT1200 by lapping a Norton 4/8K. It still works (according to the glass test) but it is smooth in use.
Large pic if you want to compare:

Spoiler

 

[Gamma]

I wouldn't sweat the marks. Mine are all marked up and they work fine.
I would not use the 1.2k for lapping anything though - I've done it, but the plate suffered.
Mine is so old/worn that I really don't care anymore but there's no reason to intentionally kill one.