Progression of grits for diamond wheels

[ells@uwaterloo.ca]

I have just purchased the T-8 and fine diamond wheel plus composite honing wheel for wood working tools such and plane blades and chisels.  After reading and viewing the excellent YouTube learning videos, I started with this with plans to build as I learn.  I was hoping that the fine diamond wheel marks might be buffed out.  I do realize that the finish will not be that of a 8000 or 16000 stone.  However upon my early starts (with light pressure on the diamond wheel) I am not getting the fine result that I hoped for. (see photo)  Before I commit to the next level of wheel I am wondering whether there is a photo of the results of a fine to very fine wheel or fine to japanese, (which I suspect is too big a jump).  Will the very fine give me the results I am looking for?   I have reviewed the very useful photos of grind marks in the Youtube video number 14 and the one that is not there is the very fine diamond stone.  Any advise appreciated!
Ells

[tgbto]

In case you are not aware of this : the diamond wheels do need a break-in period during which some diamonds will protude and leave scratch marks, including on fine stones. In my experience, the scratch marks are even more visible with the DE stone compared to the DF stone.

How long (in sharpening hours) this period lasts depends mostly on the hardness of the steels used. Pressure must be kept light at all times with diamond wheels, so that's not a way to shorten the break-in period.

I don't see a way to get rid of these scratch marks, aside from using the SG/SJ stone, which clearly negates the interest of the DF stone. Honing (or using the SJ stone) will make these marks even more clearly visible as it will smooth the small ridges but not the big ones.

Sorry I cannot be of more help!

[Ken S]

Welcome to the forum, Ells.

I agree with Tgb about the diamond wheels being coarser during a short break in period. I suggest you use your new diamond wheel for initial sharpening of about a dozen tools. Compare the scratch patterns of the first and last tools.

Keep us posted.

Ken

[RickKrung]

My view is that it is irrelevant that the diamond wheels are coarser during breakin.  That will be gone very quickly, but a DF wheel will still leave scratch marks after nominal honing.  Maybe they can be removed by aggressive buffing, but that risks destroying the newly sharpened apex, depending on how it is done. But given the OP's apparent simple approach, it probably does not include such buffing.   

I think progressively finer grits, such as the DE, SJ and then finer diamond grits (sprays/pastes) will be necessary to get good polishes without ruining the apexes.  For nearly all my work, I go through the whole routine, CBN 180, DC, DF, DE, SJ,  1µ diamond paste on a rock hard felt wheel and hanging leather strop.  I'm not trying to achieve a high polish, though, just a decent deburring.

Rick

[WimSpi]

I myself also sharpen my chisels on the Tormek T8. Started 52 years ago (at school) sharpening chisels on a rotary sandstone and then honing on a Belgian sharpening stone. But now I sharpen, to my complete satisfaction, on the T8.

Personally, I use the following stones:

- DC-250 (coarse). Sometimes chisels are so damaged that a whole new bevel has to be sharpened. But actually I always use these as the first stone, even if it's only a few strokes. It's a good start.

- DF-250 (medium). I use this one as a transition to the DE-250 (extra fine). A few strokes are sufficient.

- DE-250 (fine). This makes the grinding surface finer again. I found that to be necessary.

Because the fold is slightly concave because of the round stone, I hone the stone with a fine honingstone (the Belgian sharpening stone). Only at the edge then a very sharp and reflective surface of a few millimeters is created, and thus not on the entire surface. That is also not necessary.

The reason that I have not yet used the SJ-250 for this has to do with the fact that a chisel often needs to be wet again after some use.
But I will try it again with the SJ-250.

In the Netherlands and Belgium, all carpenters used to use the Belgian sharpeningstone. But you can also replace that with any quality honing stone, somewhere between 4000 and 8000 grid.

[I hope my explanation from Dutch to English has become understandable]

[ells@uwaterloo.ca]

Thankyou all for the helpful suggestions.  After some more sharpening experience and another review of the Tormek videos, I have purchased the very fine diamond stone.  After I break it in I hope to send you a photo of the finish with both fine and very fine sharpening.  My biggest fear is that I will really get into this and then lust over the results of the Japanese stone (it is embarrassing that a grown man can lust over a stone!)
Help has been appreciated.
Ells