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hello, I want to sharpen this carving knife:
https://www.dictum.com/en/marking-knife-kogatana-standard-double-bevel-blade-width-18-mm/710201
I read the instructions if I am not wrong the recommend using the SVD.186 R and MB-100 with one diamond stone. To me this is impossible to do. Too expensive. Isn't there another cheaper way to do it? I tried to do one free hand. I am not crazy about it, although there was an improvement compared to my previous method with waterstones.
Thanks Enrico

I believe I have dealt with a similar challenge recently, with sharpening very small, thin blades for woodworking marking knives. My blades are about 1mm (0.029") thick, 10mm wide (0.375") and 50mm (2") long.  Bevels are straight, primary at 10º and secondary 20-25º.  The secondary bevel is quite narrow. 
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I used the standard Tormek knife sharpening jigs, both SVM and KJ, but because the blades are so thin, narrow and short, had to hold them off to the side of the jig in order to get them in close enough to the grinding wheels, particularly to get the 10º primary bevel.  Keeping them level and square was also a challenge.  I had to be careful about getting the blade aligned square in the jig and the jig collar snug against the USB, all while carefully and slowly bringing the blade up to the grinding wheel. 
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It took some practice to get right and I'm not showing what some looked like, just those after I got it figured out better (except on of the six blades shown does show a bit of non-uniformity in the primary bevel).  I comment on this partly because it is just what had to be done to get the bevels right, but also because the secondary bevel on the OP's example Kogatana knife is not particularly even. 
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In both the SVM and KJ jigs, I had to use shims under the blades to be able to clamp them, because they are so thin.

The primary difficulty with this setup was keeping the blade/jig from rotating, both radially and axially.  This is what took practice and it ultimately came down to very controlled movements.  Also, I found it worked best when I used magnification (OptiVisor @ 5X) to get in close to view the placement while grinding. 

[GOOD QUALITY]

For general drilling of wood, regular steel and aluminum what type of drill bit would be best for sharpening with the DBS-22?  I am assuming that with any of the cobalt and titanium coated bits the coating would be removed on the initial shaping of the four facets?  I don't really want to spend $1000+ for a set of solid carbide bits and I fear they would be very difficult to sharpen. So is a set of plain HSS twist bits my best option?  Also can you buy bits off the shelf that are already four faceted?

Yes, I think a set of GOOD QUALITY HSS twist drill would be your best path. My main hobby is metal machining, but I do a lot of woodworking as well, along with all variety of household repairs, helping friends, etc. and I really only have GOOD QUALITY HSS twist drill sets as well as a lot of individual, loose drill bits.  For all but the hardest steels, that is all I use.  I have all kinds of carbide end mills that sometimes get used for drilling, but I would never consider getting a set of carbide drills.  I've had a few carbide centerdrills, but found they break more easily than HSS and cannot be sharpened. 

I've never bought a four-facted drill bit.  The only way I have them is having sharpened them on my T8 using the DBS-22 drill bit jig.  Their number is growing.

Assuming you have the new jig, SE-77 (please confirm) with the two little adjusting knobs (above the red ellipse in the image below), have you read and understood the manual where describes how to adjust the jig for squareness.  This has been discussed and what I and some others have posted is included in this thread, at least. 

Looks good!

I always suggest providing/including the "USB to Wheel" result, as an alternative to setting the height. Some users prefer this method of setting the USB height.
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Like me.  I won't even look at it if it doesn't include USB to wheel.  That is the only measurement I use. Period. 

 

I wanted a second SVD-186R and remembered that there had been a discussion of this when the R was released with its locking knob. I had a 186 on hand so for the conversion to a 186R I implemented Rick's idea of a collar around the jig to reinforce the tapped hole.

As can be seen in the pictures, the body of the 186 is about 2.5mm thick and the collar doubled that. There is now plenty of thread to hold the knob. (If I were Rick I would have machined a steel collar, but the 20mm ID brass bushing was so cheap ($6) and easy that I couldn't resist; I am confident that it will do the job.)

The brass bushing was a decent interference fit over the jig: I warmed the bushing, froze the jig, slid on the bushing and it tightened up nicely. If the fit hadn't been so nice, I would have put a dab of JB Weld in to keep things orderly.

Though it looks a bit bulkier in the middle, I am finding the homemade 186R to be functionally the same as my "real" 186R, so this was a successful modification for me.

Gord

Nicely done.  I think brass is a good choice here.  If I were doing it, rather than ordinary, rustable steel, I would use stainless, but I love working in brass as well and it will serve quite well and I would be happy with it this way. 

Rick

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I would suggest to start by lining up the drill to start with based on how much damage there is, broken vs severe chipping, then re-adjust as you get close to done with the primary bevel.

Yes, this what I was trying to get at, although the latter part of John's point is a good one, you don't need to just keep grinding until the flutes line up, okay/good to re-adjust them when the flutes are cleaned up so the final grinding is at the angle provided when lined up. 

Thanks Ken,  I'll have another session with that video, it appears that the cutting edge MUST be lined up, parallel to the horizontal line .... can you tell me what the other line is there for ?

I was about to describe how I rotate the drills counterclockwise when they need a lot of grinding, so that the flutes "end up" lined up with the parallel lines.  But before doing so, I thought to check the DBS-22 manual.  Lo and behold...  That is exactly what the slanted lines are for.  First mentioned on page 7 where it talks about lining the flutes up with the parallel lines, but refers readers to page 13 where it talks about the slanted lines for grinding "broken drill".  I would say one does not need to rotate all the way to the slanted lines, depending on just how much more grinding is needed to eliminate chips in the flutes, things that are less than "broken" drills?

This makes me wonder about the wisdom of starting out lining up facets of just dull drills with the parallel lines.  Why are we not rotating all drills just a little CCW from parallel so that when done, they are lines up with the parallel lines, as it says in the figure on page 13. 

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Quick question : Aren't your concerned with the plastic washer wearing down with time ?

When I looked at the stainless steel washer on the machine, it did not show significant wear.  So that is good.
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Of course, you could take your current one to a machinist friend and get it modified.

Stainless is a lot tougher than plastic.  I see "wear" indicated by the shiny ring that abuts the rubber bushing in the case. It isn't wearing down the stainless, just polishing it, but that could change for plastic, especially if not kept greased. But as Rich says, easy to print another. 

Taking a washer to a machine shop sounds nice, but it would be costly enough I think one should re-evaluate the whole situation.  Cutting a shallow concavity in that washer is not as easy as it is to say.  Easy if CNC is an option, but the time to set it up could be prohibitive for a one-off.

This seems like a solution looking for a problem.  Just put your finger on the washer as you slide the wheels off. 

Member cbwx34 here keeps links to some options in his signature line.

Member JVH here has developed a highly sophisticated and featured spreadsheet app. 

Yeah, annoying. When I remember to, which is often not, I move the wheel out enough to reach in and touch the spacer to separate it from the wheel and then finish removing the wheel.

Where does the procedure/process of deburring by "opening" the blades against each other - after having held them apart so they do not touch when closing them - fit in the scheme of scissors deburring.  I'm not sure where else I heard/saw this professed, other than Steve Bottorff, Sharpening Made Easy, but I'm pretty sure I have.

Also, I have heard/read/seen that dragging scissors through wood end grain does not adequately deburr them, meaning I believe there is some disagreement about this method. It really is only able to remove small burrs and can leave ragged tags of burrs.

What about using the MB-102 Multi-Base with the KJ-45?  Then, as noted by Rick, the side of the grinding wheel can be used.

We may not have enough information to properly troubleshoot this.  My sense of the situation is that the handles interfere with using any jigs, in particular the KJ jig; that the longer shafted SVM type jig might not have (or and extension added to the SVM shaft)  It also seems the handles and/or the handle mounts interfere with using available tool rests (because they are too wide, front to back.  That is why I suggested just using the USB as close to the wheel as possible.  I do not see how using the MB-102 provides the clearance needed, since a USB is still used in the MB-102 to get the USB over to the side of the wheel. 

I think some photos by the OP of what he has tried, showing why he is having difficulties are neede. 

Can you do it using just the USB, right up close to the wheel?  Would provide vertical support.  You'd have to regulate the angle "freehand" but the handles should give you a good "handle" on that. 

Here is an interesting video on the family of inexpensive Chinese microscopes. I think he unfairly compares them to a digital camera system and lens that costs several thousand dollars. I own a DSLR with Macro lens and  lighting that I can tether to my computer using Adobe software. It works great but it is not practical for a person sharpening multiple knives or trying to run a small business. If you make your money as a content creator it may be a different story.

I like to use a Bausch & Lomb loupe for edge inspection. Cutting a thermal receipt and feeling for resistance changes gives me a pretty good indication if I got the burr removed.

https://www.youtube.com/watch?v=_K8CtSgXREk

That is an interesting video.  I'd be interested in hearing why you think it was an unfair comparison.  I also own and use a DSLR/macro lens/lighting/tethering/focus stacking in post-processing tools. I agree it is not practical for someone doing "production" sharpening in real time, however, it could be quite useful for that same person examining edges/burrs during a process of figuring out effective deburring methods that would then get up into practice for the production sharpening process.  Even, so, I do not anticipate doing this, mainly because I have an adequate alternative, the Kingmas 60X hand microsope.  I also think the video reasonably and accurate demonstrates that the cheap USB cameras really do not deliver on their magnification claims. 

As mentioned in a prior post (above), way back, I explored high-end ($1000+) USB cameras that would do in-camera focus stacking, but still found them too fiddly and not worth it compared to the 60x hand microscope.  I also think the video acknowledges that the cheap USB cameras can be used, up to a point, to examine edges, but the much cheaper hand loupes are a more reasonable method. 

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Ideally, if you could get slightly longer diamond plates (maybe 5cm longer) that could stretch over one vertical and one horizontal USB, they can then be used for truing the wheel extremely accurately.
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I'd be concerned about concentrating the "wear" of the plate on the little bit of it that would be the only part in contact with the grinding wheel.  I think relying on the truing tool for keeping it is square and the diamond plate (used over a large range of its area) would be quite effective.  But...  I use my diamond plate "freehand", not clamped in any jig.