DMT coarse or extra coarse?

[Johnnie1801]

I need a new diamond sharpener for some re-profiling work and was wondering if the DMT coarse is enough or to go for the extra coarse? I'll be sharpening steels like M4, Maxamet, K390, S110V etc.

[The Deacon]

I have all 4 grits and, for serious re-profiling, I'd go with the extra coarse. OTOH, that's really about all it's good for. The coarse is more versatile, but it would take longer to re-profile with it.

[The Mastiff]

Agree with Paul. Always remember with DMT don't press too hard. Go up to the lower grit instead. Also, wetting with water or windex works better. Don't use oils.

Joe

[Johnnie1801]

Thanks guys, I went ahead and ordered a DMT extra coarse. I'm planning to set my bevels with the DMT and then moving to the Sharpmaker brown rods. Will that be ok or should I get something else between the DMT and brown SM rods?

[vivi]

Thanks guys, I went ahead and ordered a DMT extra coarse. I'm planning to set my bevels with the DMT and then moving to the Sharpmaker brown rods. Will that be ok or should I get something else between the DMT and brown SM rods?

That will work fine. Polishing up the entire bevel from the DMT to the Sharpmaker browns will take a minute, but there's no need for any steps between. If you're using microbevels it will take no time at all.

[kiwisailor]

Also, wetting with water or windex works better. Don't use oils.

Joe

Hi, why use windex? is it to reduce surface tension of fluid, to keep the surface cooler or grit cleaner?
Thanks (in anticipation)

[JD Spydo]

I do own and use some DMT diamond sharpening tools but I don't currently own any of their benchstones. The diamond benchstones that I currently own and use are a Norton "coarse" and a 3M extra-coarse and they both do an excellent job. I know that DMT does make decent sharpening tools but overall I've had excellent results with the Norton and 3M stones that I own and use at this time.

I really do like DMT's conical rods that I use for really beat up serrated blades and for sharpening certain woodworking tools as well. I've yet to find a diamond benchstone that I like better than the two 3M stones that I have.

[me2]

Why no oils?

[anagarika]

I use mineral oil (actually baby oil) on my DMT and it helps wiping off the swarf. I saw some other post saying oil weakened the bonding or similar effects, but I cannot observe that.

[vivi]

Why no oils?

Because there's no need.

Periodically wipe the stone with a wet rag when steel particles build up. That's all DMT's will ever need for a decade of use.

[Brock O Lee]

I use both. A DMT extra coarse is good for bulk metal removal, but it is too coarse to apex with IMO.

A good progression I find is DMT extra coarse -> DMT coarse -> SM diamond or DMT fine or SM med -> SM fine.

[Donut]

Or you can just do DMT coarse and (after thorough burr minimization) jump straight to a firm leather strop and ~0.25 micron diamond compound or diamond powder. Toothy yet refined. It'll cut rope well, shave hair, slice a free hanging paper towel (if sharpened correctly), etc... Not a polished edge but an effective one.

I'm not saying this is the best edge or anything, I'm just constantly experimenting and found that jumping from coarse to unbelievably fine has some benefits.

I've done that before, DMT coarse with a few swipes on a strop with green compound. That feels like a pretty nice edge.

[Donut]

Thanks guys, I went ahead and ordered a DMT extra coarse. I'm planning to set my bevels with the DMT and then moving to the Sharpmaker brown rods. Will that be ok or should I get something else between the DMT and brown SM rods?

That will work fine. Polishing up the entire bevel from the DMT to the Sharpmaker browns will take a minute, but there's no need for any steps between. If you're using microbevels it will take no time at all.

If you plan on getting all of the XC scratches out with the Brown Sharpmaker rods, that could take you a while, that's a pretty big jump.

If you don't care about the scratches, it's not a big jump at all. :p

[Johnnie1801]

If you plan on getting all of the XC scratches out with the Brown Sharpmaker rods, that could take you a while, that's a pretty big jump.

If you don't care about the scratches, it's not a big jump at all. :p

I tried the xc dmt yesterday on my vg-10 delica, did it nice and slow as mentioned above. It removed the steel very fast but left the scratches, not a huge deal on a work knife. After the xc I went to the brown rods (corners then flat) and then fine rods, minus the scratches it worked pretty well but I think for my nicer knives I'll have to find something between the dmt and brown rods

[VashHash]

I use the extra coarse for reprofiling and fixing damaged knives. I carry a coarse in my pocket daily. Some knives I'll actually sharpen with the extra coarse and leave it like that. Makes for a very aggressive edge. If you're using the extra coarse on a nice knife I recommend going slow and taping the blade with masking tape to avoid scratches.