DMT Aligner mod?

[cm_bushman]

Hey guys,I'm thinking of buying a DMT aligner and I notice that the lowest angle for the 1" blade width (which pretty much all of my knives fall around) comes out to 32 degrees inclusive. This is fine in my books for many knives, but I'm a fan of higher Rc steels, and would prefer edges al lower angles down to 20 degrees inclusive or close to it.

So, I notice that the lowest angle for the 4" blade width is 12 degrees per side, which is much more suitable for the higher hardness steels I have like M4. So my question is: What do you guys recommend to make a sort of extension for the DMT clamp or to affix to my knives that would hold them securely 3 inches or so away from the clamp, thus making use of the lower angles that come with it? I thought very thin pieces of plastic or metal (the maximum blade thickness for the clamp is .25"), but I worry that the materials at the appropriate thickness wouldn't be stiff enough. Or, if you guys don't think it's worth it to try, can you guys recommend a system that could reprofile and sharpen as well or better than the DMT with the ability to take edges down to around 10dps? I've looked at the Lansky, but it seems to have similar settings. I'm open to all suggestions, but I'm on a budget right now and would like to keep costs down.

P.S.) I've been trying to freehand for months, and I'm really looking for a system that's reliable and easy to use. It just hasn't taken.

 

[RevDevil]

FYI: Sharpening topics and discussions go here:
http://www.bladeforums.com/forums/forumdisplay.php/794-Maintenance-Tinkering-amp-Embellishment

 

[cm_bushman]

Sorry, I realized I should have put it in here, but only after the fact. Thank you for moving it.

 

[Jason B.]

Unless you have custom knives with individual heat treatment that angle will be fine. VERY FEW factory/production knives will handle angles below that.

That said, if you use it with benchstones you have greater control of the angle because you have more adjustment. Can't really mod it much, go too low any you start hitting the clamp.

 

[stitchawl]

That said, if you use it with benchstones you have greater control of the angle because you have more adjustment. Can't really mod it much, go too low any you start hitting the clamp.

What he said...
I often use the DMT clamp with either benchstones of wet/dry sandpaper rather than the dedicated clamp stones. Works very well. But if you are using it with sandpaper, be sure to remember to keep the guide bar OFF the paper so you don't wear it down!.


Stitchawl

 

[cm_bushman]

Unless you have custom knives with individual heat treatment that angle will be fine. VERY FEW factory/production knives will handle angles below that.

That said, if you use it with benchstones you have greater control of the angle because you have more adjustment. Can't really mod it much, go too low any you start hitting the clamp.

Thanks for the info, I' read a bit about the problems when some people tried to go lower with the Aligner. I'll have to look into other systems I suppose, though I don't see anything in my price range right now, aside from the DMT and Lansky, the only other contender for my needs seems to be the Edge Pro, and that's a bit of cash.

As I said, I've tried stones for months with rough results. I only have two pocket stones (an old EZE-Lap Diamond and a "Cutter's Edge" Soft Arkansas) and a grey stone that I have no idea about (water stone, oil, india, SiC?), aside from it's being what I'd equate to a medium grit (between a coarse and fine DMT) so it may be my materials, though I like to think it's my lack of skill. I may go for a cheap Norton combo stone or a coarse/fine Duosharp and see if I get better results if that's all I can expect out of systems below $100.

What he said...
I often use the DMT clamp with either benchstones of wet/dry sandpaper rather than the dedicated clamp stones. Works very well. But if you are using it with sandpaper, be sure to remember to keep the guide bar OFF the paper so you don't wear it down!.


Stitchawl

Thanks for the tip, I'm a big proponent of stropping, and I had planned to make a wood and leather "stone" if and when I got my Aligner. I always wondered about sandpaper, and why people don't use it more often. If would appear to be a cheap and common sharpening solution when paired with a piece of hardwood and some glue. Of course, I don't know if there are other factors involved, such as the sandpaper wearing out quickly or being inferior to stones in some way.

What's your experience?

 

[Jason B.]

I would say lack of proper sharpening equipment is a issue.

 

[bdmicarta]

I think you can mod the Aligner clamp to get your angles a bit lower, but I don't know what the lower limit is for your size blade. As you lower the angles you will hit the end of the clamp, I think I hit it at the point where the brass screw and bushing are. You could file down these areas a bit with a standard file to give more relief without changing the function of the device.

I have also considered removing the standard plastic pegs and replacing them with small eye-bolts with long shanks and 2 nuts. This would allow a wider range of adjustments than the plastic pegs, and you could set them to any angle you want instead of just preset angles.

Thinking about it a little bit more- if you are handy with tools you could make your own clamp from a couple of pieces of sheet metal. Basically the clamp needs a bolt through it near the spine of the blade to hold the 2 pieces together, and it needs to hold the plastic pegs. If you replaced the pegs with threaded eye-bolts then all you would need is a couple of holes drilled through the pieces of sheet metal. Cut 2 rectangular pieces of sheet metal, drill some holes, and you are done.

 

[Obsessed with Edges]

One way to extend the blade edge further beyond the clamp's front edge, and therefore lower the effective sharpening angle, is to 'shim' the clamp with a suitable piece of any material that closely replicates the thickness of the blade, such as seen below. I used a piece of zip-tie as the shim behind the blade's spine, which worked well with the main spear blade of a Victorinox SAK:

As others have said, using the Aligner clamp with bench stones gives some wider leeway with sharpening angles. Works quite well, and that is my preferred method for using the Aligner clamp. Sometimes can work to one's detriment however, if the angle gets too low. I used my Aligner clamp to re-bevel a ZDP-189 Leek recently (without the shim), on a DMT Duo-Sharp C/F bench hone. Not sure what the actual finished angle was, but it was well inside 30° inclusive (bevel width about ~1/8" on that thin blade). Went like gang-busters, but I found out the hard way that I went too thin with it, when the tip of my newly-sharpened blade broke.


David

 

[stitchawl]

Quote Originally Posted by stitchawl View Post
What he said...
I often use the DMT clamp with either benchstones of wet/dry sandpaper rather than the dedicated clamp stones. Works very well. But if you are using it with sandpaper, be sure to remember to keep the guide bar OFF the paper so you don't wear it down!.
Stitchawl

Thanks for the tip, I'm a big proponent of stropping, and I had planned to make a wood and leather "stone" if and when I got my Aligner. I always wondered about sandpaper, and why people don't use it more often. If would appear to be a cheap and common sharpening solution when paired with a piece of hardwood and some glue. Of course, I don't know if there are other factors involved, such as the sandpaper wearing out quickly or being inferior to stones in some way.

What's your experience?

There are two main disadvantages.
The two negatives are that the sandpaper wears out faster than stone, and you usually can't find grit sizes smaller than 2,000. That's it. If you don't mind spending 75 cent's to sharpen your knife, the first really isn't a problem. And if you don't need to sharpen finer than 2,000, neither is the second. I'm able to find sheets down to 10,000 should I feel the need, and one can always use the same methods using sheets of polishing film too.

The advantages are, to me, portability, speed, convenience, and angle control.
Portability in that the plastic clamp weighs next to nothing and takes up almost no space in a backpack along with a couple of sheets of sandpaper for in-the-woods sharpening. Speed... a sheet of 120 grit wet/dry sandpaper removes a lot of metal quickly, and progressing through the grits, when using full sized sheets of paper goes fast. Convenience? Clean to use, easy to store. And angle control to virtually ANY angle you want simply by raising up the level of the abrasive, be it stone or paper, while keeping the guide rod down on the table. Want a 4 degree edge? No problem... until you try to cut something, that is...

Stitchawl

 

[cm_bushman]

Wow, a lot to think about now...

I would say lack of proper sharpening equipment is a issue.

I've thought so for a while now. I don't see how my hodge-podge assortment of stones could get more out of sync. When I see other sharpening threads, however, you always see the advice to avoid buying good stones and work with what you have. What I have is pitiful, in my view, and since it's not working for me, I'm going to move in a different direction.

Thinking about it a little bit more- if you are handy with tools you could make your own clamp from a couple of pieces of sheet metal. Basically the clamp needs a bolt through it near the spine of the blade to hold the 2 pieces together, and it needs to hold the plastic pegs. If you replaced the pegs with threaded eye-bolts then all you would need is a couple of holes drilled through the pieces of sheet metal. Cut 2 rectangular pieces of sheet metal, drill some holes, and you are done.

I've thought of home-brewing a clamp, though I would base it more around the Lansky. Basically, I would bend two ~8" pieces of thin (1/8"), flat (1" wide) angle iron or aluminum into an "L" and placing a bolt through one leg and drilling holes in the other. It seems simple, even with hand tools, but I can't say for sure until it's together and working! Then, if I bought the Aligner, I'd have great stones and holders at my disposal as well. Does anyone know if you can buy the DMT stone holders a la carte?

One way to extend the blade edge further beyond the clamp's front edge, and therefore lower the effective sharpening angle, is to 'shim' the clamp with a suitable piece of any material that closely replicates the thickness of the blade, such as seen below. I used a piece of zip-tie as the shim behind the blade's spine, which worked well with the main spear blade of a Victorinox SAK:

As others have said, using the Aligner clamp with bench stones gives some wider leeway with sharpening angles.

David

That's almost exactly what I meant in the OP, thanks! I've given up on the 3" blade extender, but it was nice to see someone at least had the same idea, and actually put it to use!

If I ever do invest in a full range of benchstones, I'll likely use the Aligner clamp like you say as a transition to frehand sharpening (If I can ever kick the training wheels!) I don't like the idea of being tied to a system with multiple components if anything ever happened and I needed to do a full resharpening while out in the woods.

There are two main disadvantages.
The two negatives are that the sandpaper wears out faster than stone, and you usually can't find grit sizes smaller than 2,000. That's it. If you don't mind spending 75 cent's to sharpen your knife, the first really isn't a problem. And if you don't need to sharpen finer than 2,000, neither is the second. I'm able to find sheets down to 10,000 should I feel the need, and one can always use the same methods using sheets of polishing film too.

The advantages are, to me, portability, speed, convenience, and angle control.
Portability in that the plastic clamp weighs next to nothing and takes up almost no space in a backpack along with a couple of sheets of sandpaper for in-the-woods sharpening. Speed... a sheet of 120 grit wet/dry sandpaper removes a lot of metal quickly, and progressing through the grits, when using full sized sheets of paper goes fast. Convenience? Clean to use, easy to store. And angle control to virtually ANY angle you want simply by raising up the level of the abrasive, be it stone or paper, while keeping the guide rod down on the table. Want a 4 degree edge? No problem... until you try to cut something, that is...

Stitchawl

Thanks Stitch, I've always wondered if there was a reason that made Sandpaper unsuitable. Searching the forum turns up mostly Convex/Mousepad sandpaper sharpening advice than more conventional grind techniques.

I may try sandpaper before I go for the aligner, as a surrogate set of Bench-stones at a far lower cost. I've heard the AlOx automotive paper is best for the higher grits and in general, is this your experience or do you have a favorite type/brand? Using the "Grand Unified Grit Chart", I got 220, 400, 800, 1500, and maybe 2000 for approximating the DMT hierarchy from Extra Coarse to Extra Fine. Do you think this is a good set to start with?

 

[stitchawl]

Thanks Stitch, I've always wondered if there was a reason that made Sandpaper unsuitable. Searching the forum turns up mostly Convex/Mousepad sandpaper sharpening advice than more conventional grind techniques.

That was the commonly used method for convexing edges. I prefer bevels for most of my knives, so always use the sandpaper on a flat, hard surface.

I've heard the AlOx automotive paper is best for the higher grits and in general, is this your experience or do you have a favorite type/brand?

I live in Asia. I can't even read the brands on half the products I buy. But I DO insist on good quality wet/dry automotive sandpaper, rather than stuff sold in the discount stores in mixed bundles.

Using the "Grand Unified Grit Chart", I got 220, 400, 800, 1500, and maybe 2000 for approximating the DMT hierarchy from Extra Coarse to Extra Fine. Do you think this is a good set to start with?

A very good start. I'd probably only use the 220 if I needed to reprofile an edge, but the 400, 800, (I'd add 1,000 rather the 1,500) and 2,000 should see you through some damn fine edges. Finish up on a hard strop loaded with Chromium Oxide, and you can't hardly beat it.

Stitchawl

 

[EdgePal]

Sharpening tools made in US are constructed for US sharpening angles who are very high - compare to the rest of the world, often around 40 degrees total edge angle. US sharpening tools are made for the US market.

In for example Scandinavia and the rest of Europe, the normal edge angle is around 20 degrees total edge = 10 degree per side. Our sharpening tools are constructed to be able to sharpen edges in that angles.

Thomas

 

[Jason B.]

^^^ yeah, like stones. Lol!

 

[cm_bushman]

Thanks again, Stitch. I think I'll go with your recommendation on sandpaper and try to put my own clamp together. I have an idea that would allow for very low angles using magnets and some flat Al. bars or angle iron. My only concern is versatility and the strength of the magnets. I also need a way to make nice square bends on the metal and a holder for the paper or stones. I'll have to check up and see if I can get those DMT stone holders without the rest of the system. They seem to work well enough.

This whole setup should end up costing less than a full range (XC-XXF) of benchstones too, which is music to my ears!

 

[stitchawl]

Thanks again, Stitch. I think I'll go with your recommendation on sandpaper and try to put my own clamp together. I have an idea that would allow for very low angles using magnets and some flat Al. bars or angle iron. My only concern is versatility and the strength of the magnets.

Don't let magnets be your concern. If you have any old broken hard disk drives around, or a repair shop that will give you a couple of broken one, you can find the "Magnets from Hell" inside them! Actually so powerful that if you accidentally let two of them snap together on the edge of your finger, they will raise a blood blister!! All you need is a Torx driver to open the case (be aware that there usually are one or two screws UNDER the paper label...) then either a vise and a pair of vice-grips or two large pliers to bend the magnet mounts away from the magnets themselves. (The arrow is pointing at the curved mounts. The magnets are on the inside.) At the base of the 'read/write' arm inside the drive, there is a thin, flat, very powerful magnet on either side. Remove the arm base and you'll see them inside. Just bend the base so you can work a flat-blade screwdriver under the magnet, and pry it off. I make inverted sheaths using two of these magnets to retain the knives. NO STRAPS. Only two-three magnets, and it will retain a K-bar, even jumping up and down!

There are two magnets inside each hard drive. These are very brittle and will break easily, but then you just have smaller really powerful magnets!


Stitchawl

 

[cm_bushman]

Thanks again Stitch, I'll likely just order some small disk magnets from the net, along with the Aluminum angle I'll need. They're dirt cheap for 10, 30, or 100 N50 grades in a wide range of diameters and thicknesses. I'll be putting this together with a drill press and hand tools, so I'm going for as simple and standardized as possible. It really does seem simple to set up a sharpening jig like the Aligner or Lansky, though the form factor does have limitations that I'm trying to minimize.

Thin mild steel rod, hard rubber sanding blocks, glue, and sandpaper make for great "stone holders" for the system too, or at least I figure it's a good, cheap idea.