DMT Aligner Help

Joined
May 19, 2006
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Hi,
At the suggestion of several folks on here, I bought a DMT aligner set to use for sharpening, in addition to my sharpmaker.

Unfortunately, I seem to make sharp knives dull on this thing! I am starting with the coarsest and go to the finest and still can't seem to get it right.

Is there an instructional video somewhere or does anyone have any sage advice. I would like to use it for those knives I want to reprofile or for harder steels. My sharpmaker fits most of my everday needs, but I have some Queen D2 steels that don't quite take to the SM.

Thank you,
Brett
 
Don't switch to the finer hones until you get the knife sharp with the coarse hone. Queens can take a long time to grind that thicker D2 edge down to the angle your useing.
:)
Heck we could even say that some Queen knives have an obtuse edge. :)
 
What angle do you think I should sharpen at?

I have been doing 15 I think.

Thanks,
Brett
 
15 per side sounds like a good angle to me. What is the knife and what is the useage?
 
That sounds like a good angle to me. What is the knife and what is the useage?

It's the dogleg jack and is used for office tasks like cutting tape, etc.

The 15 I have been doing is each side, not inclusive.

THANKS!

Brett
 
That will likely take forever and a day- Queen edges are pretty thick. However, once it gets there, you're going to be impressed with its performance.
 
How sharp is the knife after the most coarse stone? Forget about the angle for now, that does not matter in regards to sharpness anyway.

-Cliff
 
How sharp is the knife after the most coarse stone? Forget about the angle for now, that does not matter in regards to sharpness anyway.

-Cliff

Hi Cliff,
Not very sharp after the first stone. I am thinking maybe my technique isn't correct.

thanks for your help,
Brett
 
Take the knife and grind it lightly right into the fine stone, just 1-2 passes very light so the edge is now flat and reflects light fully along its length. Now go back to the coarse stone and do just 3-4 passes per side. What does the edge look like?

-Cliff
 
Take the knife and grind it lightly right into the fine stone, just 1-2 passes very light so the edge is now flat and reflects light fully along its length. Now go back to the coarse stone and do just 3-4 passes per side. What does the edge look like?

-Cliff

Hi Cliff,
Do you mean to grind the cutting edge to dull it? Then do regular passes of the stones?

Thanks,
Brett
 
Brett,

Yeah - he means to purposely dull the knife by cutting it across the fine stone a few times to essentially flatten the edge. The knife is a bit easier to sharpen when it is uniformly dull. Then proceed to the course stone. I'm not sure if Cliff was aware that you are using an angle guided system though - and I think that is where he is comeing from in terms of the angle doesn't matter yet (hand sharpening?)

As the others are eluding to, it sounds like you are sharpening your knife at a much steeper angle than the factory edge. This causes the stone to start removing metal off the back of the edge as it sets a new primary bevel. It can take a lot of time to get that shoulder metal off and begin hitting the edge.

One trick that many people use is to use a sharpie to color along the entire edge about 1/4" up the blade. Now run your course stone at the preset angle for a couple of strokes. This will show you where the stone is contacting the blade. If the stone is at the edge than things will proceed quickly.

If it is taking metal off higher at the shoulder you have two choices: 1) use a higher angle e.g. 20, or 25o and see if that results in removing metal at the edge. This will sharpen your knife at the factory set angle. 2) keep going at it at your preset angle of 15o. It will take you a while (maybe one or two hours) but eventually you will get there. After about 20 minutes, re-try the sharpie thing.

Finally, when you are sharpening - do only one side at a time and proceed on that side until you produce a course burr. Then switch to the other side of the knife and again keep at it until the burr flips to the other side. You always make your decision to switch sides when the burr has been passed over to the other side. If you don't do this, you won't get your knife sharp even if it is at the right angle.

Good luck!
 
Yes, the reason you dull it uniformly is that this will allow you to judge exactly the effect of the stone. If it removes the flat edge quickly then you are honing at the angle necessary to sharpen the edge. If it is not then you need to either increase the angle or grind until the edge is hit, that can take up to an hour or so, depending on the steel and coarseness of the stone.

When I said that the angle does not matter, it was simply that even very obtuse angles like 25 degrees per side can push cut paper and shave very smoothly. So if they are not getting sharp then making the angle more acute is not the best solution. Of course if the knife does not cut well in general then the angle most likely needs to be changed.

-Cliff
 
D2 is curious stuff. It takes significantly longer to achieve that hair popping edge, I find, so you just have to be patient. My new Dozier K1 General Purpose came with a hair shaving edge, which I've been able to improve to hair popping with some time and patience on a DMT ultra-fine hone. It just takes longer than with most steels.
 
Ed definately has a point there, the grindability of D2 is very low, for such steels I would really suggest microbeveling.

-Cliff
 
If you are having to remove a fair amount of steel to get the 15 degree angle, then be careful about going for a burr too early. I have had knives where this resulted in very different bevels on the two sides of the blade.
My suggestion would be to grind for a while on each side, evening up the size of the bevel until you get close. Then use the sharpie (black marker) trick and begin feeling for a burr.
Re-beveling a very thick edge, with a high angle bevel, and on wear-resistant steel, can indeed take up to a couple of hours. Once you have achieved the edge you want, however, re-sharpening is easy and fairly quick.
I see re-beveling as a "custom" modification and that helps increase the enjoyment I get from the end product. I've done several knives that way with a DMT Aligner.
Greg
 
If you are having to remove a fair amount of steel to get the 15 degree angle, then be careful about going for a burr too early. I have had knives where this resulted in very different bevels on the two sides of the blade.

Changing the angle, even dramatically, can not force the bevel to go uneven if you just grind to a burr on one side. The bevels can only go uneven if you grind more on one side after the burr has formed, keep grinding it pushing the bevel off center.

However often the origional production primary grinds are off on a lot of knives and to compensate for this the edges are hand sharpened at different angles so they will be the same width. When you have one bevel at 25 and the other at 20 and you reduce them both to 15, one is way wider than the other.

-Cliff
 
Changing the angle, even dramatically, can not force the bevel to go uneven
Correct it isn't from changeing the angle it is grinding on one side too much that moves the edge off center and produces the uneven bevels.
The bevels can only go uneven if you grind more on one side after the burr has formed, keep grinding it pushing the bevel off center.
Correct, and on very dull knives the burr will not form until you have ground well past center. That is why it is a good idea to do as Greg suggests.
However often the origional production primary grinds are off on a lot of knives and to compensate for this the edges are hand sharpened at different angles so they will be the same width
Yes this can also be the reason for uneven bevels but it is more likely you've sharpened on one side more than the other. A degree or to on the factory main grind isn't really going to show its self that often on your edge bevels.
 
Forgive me for jumping into this so late. You probably have moved on, however I wanted to add a few things to this discussion.

You may or may not already know that the aligner produces an edge that varies a degree or two along the length of the edge. This variance is different depending on the shape and length of your blade. I found out that if I clamp my Endura all the way at the base of the blade, then my angle is nearly the same, while if I clamped right at the center, then my angle changed by nearly two degrees from heel to tip. This effect would be much different on a knife whose blade width doesnt change along its length(and I would recommend clamping in the center in this case.)

With that said, you need to pay careful attention where you clamp your knife each sharpening session. I use a stone to scratch hash marks on either side of the clamp on the spine of the knife. Also, I'm not entirely convinced that the clamp matches angles on each side, so I would try to clamp with the thumb screw on the same side, say on the logo side. The thumbscrew also changes the angle, and I would tighten it down till it stops flush to ensure that you maintain the same angle from session to session. These steps will go far to reduce the amount of work you have to do each time you sharpen.

I have a ZDP and an S30v spyderco that I can get shaving sharp with the ex coarse stone. It's a gritty edge that scrapes the skin and kinda pulls the hair, but it will remove hair. I have been using my kit for about four years, and I still use a black marker two or three times each session. Mark the edge and work on it till there isn't any inkling of black left at the edge. Mark it again, and the black should disappear with just a few swipes. At this point, there should also be a burr along the entire length of the other side. Repeat on the other side, and there shoud be a burr on the first side.

Now you want to delicately remove the burr(with the same stone). Do this by alternately working each side with anywhere from five to twenty swipes per side(depending on the width of your bevel), and progressively get lighter each time you change sides. Be careful to maintain constant pressure each set of swipes, and be careful to get lighter each time you change sides. Do this about four or five sets of swipes, until you are just barely applying pressure(the lighter the better). It should also be noted that on this step, you should try swiping the entire length of your blade with one swipe. When you get to the lightest pressure possible, progressively lower the number of swipes per side(say 10,5,3,2,1). As an added measure, repeat the 2 swipes and the 1 swipe a few times to minimize any burr that may be there.

This step done properly should produce a nominally shaving sharp edge with the ex coarse stone. This will also be a mean slicing edge. After you get this result, you can move on to the next stone.

A quicker method of doing this is to produce the burr on the ex coarse and then move on to the next stone and produce a burr, but I prefer to get a premium edge with each stone before I move on to the next.

If you need to remove a lot of steel, there is an xx coarse stone available that fits the aligner. It is in the ski section on the DMT sight. It works beautifully.

One last note, I wouln't recomment using the aligner and the sharpmaker in conjunction with each other. You could use the aligner to rebevel, and then the sharpmaker to apply a higher microbevel, but you will have difficulty getting the angles to match from the aligner to the sharpmaker.
 
Nosetail,
Thanks for your great advice. I kind of left it alone but plan on tinkering on an old knife with the aligner tonight.

I will keep you posted.

Take care,
Brett
 
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