Round knife sharpening jig version 3

3

The version 2 sharpening jig was okay but it was flawed in several ways. Some of the issues were due to lack of proper material/tools. The angle brackets were simply not ridgid enough to eliminate all unwanted movement. This could be fixed if I had access to welding equipment (and knew how to operate it) The size of the round knife blade itself also causes problems as it flexes if you press too hard while sharpening.

The universal joints are also a bit loose and the current 3d printed parts are also not without play.

All of these issues could be fixed but one thing that would be hard to change is the fact that the pivot point is not in the center of the blade. This causes the bevel angle to change from the points to the top of the knife. With the current design we a looking at something like 5 degrees which is quite a lot.

The need for a new jig came as I purchased a new round knife. The version 2 is not very suitable for different sizes of knifes and the new one simply did not fit.

Therefore I came up with a new idea which incorporates the best of the two previews versions.

Pros

• Knife blade securely held in place without the possibility for any unwanted movement
• Pivot point in center of blade
• small overall size

Cons:

• A bit cumbersome to shift grinding/honing from one side to another.
• only short strokes with the sandpaper is possible. 
• Each knife needs its own platform.

I was playing around with the dimensions while I was building it so everything is cut very rough. Also I have no propper workbench for woodworking and only very limited tools.

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Round knife sharpening jig version 2

5

I have made a sharpening jig for a round knife before as you can see here. The design was inspired by the apex edge pro. This time around I will base the sharpening jig around the wicked edge. Even though the first jig is able to put a decent edge on the round knife there are still too many "unknowns" The biggest problem as I see it is that you need to move the stone and the round knife at the same time. This will result in some unevenness in on the edge if you do not do it exactly the same each stroke.

With this new design you take out the movement of the round knife completely. The design is based on the wicked edge after seeing this video where Clay Allison sharpens a round knife. The wicked edge is not designed to deal with a knife like the round knife so he has to sharpen it in two sessions as he needs to reposition the knife. Being able to have the base of the swivel rod in the center line of the round knife will solve this problem. The repositioning of the knife is not that big of a deal and I could live with that.. The price on the wicked edge is however insane. As I have not been able to find a European deal I would have to buy it from he USA. The standard package is 299$ but that only goes to 600 grit. You would at a minimum need the pro pack I costing 425$. Adding to this is shipping, 25% in VAT + 12% customs + 23$ in customs fee. I dont know what the shipping is but the total without shipping comes in at a whopping 605,25$. I am not willing to spend that much on a sharpening system at this point.

For further inspiration as how to make the jig I watched these two videos Wicked Lansky and Lansky sharpening system modified...

They both use the lansky sharpening system as a base but uses universal joints and socket extensions bars to guide the sharpening stones. I almost bought the lansky system but came to the conclusion that the clamp would not hold the round knife very well. Also with the wicked edge system you really need two stones of each grit. Instead of the stones I will be using 3m micro finishing film and 3m lapping film using the "scary sharp" principle. The most informative site regarding sharpening that I have ever seen is this one:
http://www3.telus.net/BrentBeach/Sharpen/sitemap.html
Brent Beach really likes to sharpen plane irons using 3m paper with a simple but effective jig. Everything he says is well documented and often very controversial. The best quote from the site is this:

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