Ionut's Small Knife Jig

[grepper]

  Herman, and Ionut.  Very cool.

[Herman Trivilino]

I discovered another feature of this homemade jig that's important.  You want the metal platform no wider than the width of the grindstone.  I had to trim a bit off the edge today because I was sharpening a knife with no bolster (is that the right way to say it) and I couldn't get the handle close enough to the grindstone to sharpen that end of the blade.

Here's the latest version of the jig:

[Herman Trivilino]

Here's a picture showing how I was now able to get the grindstone all the way up to the end of the blade closest to the handle.

(The little magnet is there holding the knife in place for the photographer's benefit.)

[Herman Trivilino]

And here's a photo showing how nicely this jig allows the curved knife tip to approach the grindstone.

[Herman Trivilino]

Does that knife look familiar to anyone?  I picked it up in my travels many years ago while visiting the Warther Museum in Dover, Ohio.  David Warther was a very famous wood carver.  The knife is stamped

WARTHER & SON
DOVER, OHIO

He made his own carving tools with the handles custom made to the shape of his own hand!

I've sharpened this knife freehand many times over the years so I have no idea what the original edge angle was.  It sharpened nicely to 30^o, and the steel is so hard I had to set the grindstone coarse to get the bevel shaped.  It passes every one of the sharpness tests!

[Ken S]

Herman,

All you would have had to do was drive back to Dover, ohio and the people at Warther would have sharpened you knife for free for you.

Ken

ps I think that's a great marketing strategy.  A good value for the customer and also another buying opportunity.

[Herman Trivilino]

I do remember the lifetime free sharpening service that comes with their knives.  I was thinking about that today when I was deciding on the edge angle.  If I took it back and had them sharpen it, I could then measure the angle!

This gets me thinking about the steel and the edge angle.  This steel is very hard, and it's also tarnish free.  So, if I remember Ron Hock's comments correctly, this means that this type of steel will not be so good at holding up to abuse.  Therefore, it would be wise to choose the edge angle correctly as a compromise between sharpness and durability.

[Herman Trivilino]

The next step in development of this jig would be to experiment with different platform lengths. Mine is 4.25 inches and seems to work just fine over the range of edge angles needed for knife sharpening.  At first I thought it would be necessary to have a set up where the platform length would be variable, as it is in Ionut's original prototype, but of course I soon found out otherwise.

Another improvement would be to make the jig out of a piece of angle aluminum.



It would have a width of 2", a length of about 4", and the lip along the long edge would only need to be about 0.25" wider than the the thickness of the platform.  This lip would rest against the edge of the scissor jig base and then the platform could be attached to the scissor jig base with only one screw!

[Ken S]

Good thought, Herman.  I would suggest making a very simple jig (block of wood with a hole in it).  That would make it easy to drill matching holes in any subsequent platforms which would be interchangeable.

I find this process of adapting and modifying the Tormek fascinating.  Not every path will be successful, but the end results should push back our knowledge frontier.

Ken

[Herman Trivilino]

Good idea about the wooden prototypes.  Wood is easier to work with for woodworkers!

I have lots of pieces of scrap wood lying about.  Can't say the same for scrap metal.

[Herman Trivilino]

I uploaded a video demonstration of this jig.  Tried Photobucket but it wouldn't take, so I used YouTube.

Here's the link: http://youtu.be/AcWAkQmoU8c

If the link doesn't work try a Google search for "Tormek Knife Jig" by yours truly.

[grepper]

That's beautiful Herman!  Congrats.  I love the way it can sharpen a machete or a pen knife.  And you know what's really cool?  Simply beautiful and beautifully simple.  Really fine job there Herman.  Way to go!  Isn't modding fun!

What if your video goes viral, and drives a million visitors to the forum?

You mentioned long video uploads and how Photobucket choked on it.  I don't know how much of an issue this is for you, but I imagine if you are using your digital camera to make the video, the video is either a .MOV or a .MP4 format and the file size is probably quite large.

You can probably reduce the file size through your camera settings by selecting the dimensions to a smaller size, like 320x200 or 640x480 etc, and/or lowering the frame rate.

Once recorded and saved on your computer, another thing that you can do to reduce file size is to convert the video to a different file format, possibly WMV, and/or reduce the dimensions of the video. 

You can do that with this great free program Format Factory.  It can convert just about any video format to any other, change the dimensions of the video, and also let's you select the audio quality.  Audio is a huge portion of the file size, and stereo audio doubles the size of the audio portion.  There is no reason why demo videos need to be in stereo. (Mono may be an option in your camera too).  It also has a bunch of preset sizes that makes it very easy.  With a little experimentation you should be able to reduce the file size of your videos by up to 75%

Format Factory:
http://www.pcfreetime.com/

[grepper]

I am going to make something similar to the Ionut-Herman, or IoHerm, or iHerm or IH jig, as I can see it is most useful!  If you have ever tried to sharpen a machete, or pocket knives, or very thin bladed knives without it, you quickly understand it's indespensible.

But it caused me to wonder.... 

Q:  It's so simple and obvious, why didn't the Tromek engineers make one in the first place?

Could it be:

1. They are a bunch of engineering types and the simplicity eluded them?
2  The didn't think anyone would want to sharpen small or thin knives?

Q: Can the standard tool rest be used to sharpen a machete?

Q: Is there any advantage to the small knife jig (skj) over the IH jig for sharpening knives large enough to use the skj?

1. Is it that the skj allows rolling the knife perpendicularly away from the wheel as you sharpen the curve towards the tip so as to keep an even bevel?
2. Is it because you can micro-adjust using the handle of the skj?

[Herman Trivilino]

That's beautiful Herman!

Thanks, Mark.  And thanks for the tips on the video editing.  I managed to get a smaller (lower quality) version uploaded to photobucket. And here it is ...

[ionut]

Hi Herman,

That really looks great, and you did a really great job documenting it. I bet not long after this we will see a small/huge knife jig in the Tormek accessories lineup.
Wood is good for prototyping, but not long lasting if you want to have a definitive solution. Aluminum is the best as you say it in the video, you can also rout it, and a short routed socket in the center along the length of the platform, where there would be a knob to tighten it would allow you to move the platform closer/further to/from the stone without having to disturb the universal support adjustment. But I don't really believe that would be needed, you have all the adjustment required.
Also if the jig would be 1/4" or a bit more thick you would have enough clearance from the scissors platform in case of knife wooden handles.

All the best,
Ionut