Thanks to Ionut for his advice on how to make a jig for sharpening small knives.
You can see his original here:
http://forum.tormek.com/index.php?topic=1191.msg3308#msg3308
With a photograph here:
https://skydrive.live.com/?cid=bc168f3568163031&id=BC168F3568163031%21299&Bsrc=EMSHOO&Bpub=SN.Notifications&sff=1
So yesterday I decided to make my own ...
(http://i1291.photobucket.com/albums/b553/htrivilino/007_zpsbbfa1b5a.jpg)
I made my platform out of an old lawn edger blade, and since I don't have the tool rest I used the base of the scissors jig.
After seeing this Ionut advised me to grind a taper on the end so I could get more of the knife on the platform and to flip the c-clamps over so they'd be out of my way.
I tried that this morning with great success but I was having trouble controlling the knife. With the grindstone turning away from the knife edge it kept wanting to lift off the platform.
So I decided to grind towards the edge ...
(http://i1291.photobucket.com/albums/b553/htrivilino/001_zps185d83d6.jpg)
This worked great. I had perfect control.
(http://i1291.photobucket.com/albums/b553/htrivilino/002_zpsd672a4fb.jpg)
I found an old steak knife with a serrated edge and decided it would be sacrificed for test purposes. It has a length of about 13 cm and a width of about 2 cm. First I ground away the serrations with the grindstone coarse, then finished it with the grindstone fine.
(http://i1291.photobucket.com/albums/b553/htrivilino/003_zps5070d1f9.jpg)
I was able to get the platform so close to the grindstone that the gap was always filled with water.
(http://i1291.photobucket.com/albums/b553/htrivilino/004_zpsa3c70e85.jpg)
Now I just have to get up the nerve to try it out on one of my good pocket knives.
Well done, Herman. You get the Yankee Ingenuity award!
Ken
I particularly like the green improvised adjustment nut in the US. presumably that's the one you were posting about the other day
Quote from: Rob on March 10, 2013, 09:50:15 PM
I particularly like the green improvised adjustment nut in the US. presumably that's the one you were posting about the other day
Yes, and it works nicely with this jig. I can set the angle with the platform resting on the grindstone, then turn the micro adjuster on the universal support to raise the platform just a fuzz above the grindstone.
I sharpened one of my pocket knives using the new jig. You can see that I still need some practice. The bevel width varies. But this has promise as it can sharpen the smallest of blades.
(http://i1291.photobucket.com/albums/b553/htrivilino/006_zpsba93baac.jpg)
Here's another photo of the pocket knife.
(http://i1291.photobucket.com/albums/b553/htrivilino/005_zps6aef1b3d.jpg)
I'm thinking of drilling and tapping two holes in the base of the scissor jig so that the platform can be attached with screws instead of c-clamps. I'm finding that there's no need to adjust the platform position relative to the base of the scissor jig. Adjusting the height of the universal support, and rotating the base of the scissor jig on the universal support, provide enough adjustment.
I can see how this jig may surpass the knife jig for sharpening all knives, not just small ones. One advantage it has is that it keeps the bevel angle constant all the way to the knife tip.
Patent quick!
Made some further modifications. Drilled holes through the scissor jig base and tapped them. Used two phillips head screws to attach platform. I need to countersink those screw heads but I don't have a drill bit that'll do that to that tool steel. Ideally this platform should be made of aluminum.
(http://i1291.photobucket.com/albums/b553/htrivilino/002_zps79a49bf9.jpg)
Looks very nice, Herman. Do a little hillbilly machining on the perimeter and it will be professional! The knob looks great as well.
That looks great Herman, and it is much better using it against the blade, it is much easier to control. I am glad it works well for you.
Ionut
Hey Herman,
I wonder if you could drill just one hole through your metal plate, centered, just behind the trailing edge, (away from the wheel), of the scissors jig tool rest, and then put a single screw down through the top of the plate just like the two screws you have now.
Then make a small metal bar with a hole in it towards one end that would slide up the screw and extend under the scissors jig tool rest on the other end. You could then get a nice knob like you used to make the control bar micro adjuster, which would tighten, going up the screw, pressing the small bar against the bottom of the scissors tool rest, thereby clamping the metal plate to the scissors tool rest.
Then when you wanted to use it, there would be almost no setup time. Just slide it on, clamp it down and Bob's.... (Doh!... Rob!) your uncle. No messing around with screws and nuts, and it would work with no modification to the scissors rest.
Does that description make sense?
Or maybe even, dare I say..., two screws like you have now with a square metal plate with two knobs on the bottom. That would allow you to push the two screws up against the trailing edge of the tool rest to help center it.
I have no idea if that could hold the plate tightly enough against the tool rest, or what other puzzlements might pop up during testing, but it was an idea that came to mind as I was admiring your version if Ionut's jig idea.
Or maybe even copy the fulcrum idea like the clamp on the small knife jig???
Quote from: Herman Trivilino on March 11, 2013, 01:24:18 AM
I can see how this jig may surpass the knife jig for sharpening all knives, not just small ones. One advantage it has is that it keeps the bevel angle constant all the way to the knife tip.
I like this, Herman. It didn't register with the first reading.
This was what I was referring to in a different post in another thread. I personally like the bevel angle to be the same all the way to the point of the tip. Yes, the width of the bevel grind will become greater on the tip, but remember the tip as it goes out to the point, gets thicker. The width of the bevel will have to increase for the bevel angle to remain the same.
See: http://forum.tormek.com/index.php?topic=1191.msg5104#msg5104
That's my preference and I know not everybody agrees. I still like my DMT Aligner for my own personal knives because of that reason. But Herman's statement confirmed what I have wondered ever since reading Ionut's original small knife jig posting several weeks ago.
I wish you guys would have designed this before I sharpened my first machete. It seems like it would have worked nicely for that, and for other very long blades for that matter. Might have to remove the honing wheel.
Good thought, Mark. I had a young fellow at church, yesterday, ask me to sharpen a machete for him. Wasn't looking forward repositioning it in the knife jig. That or the tool rest would be the ticket.
Elden,
Check out my SVD-45 jig described in my recent post. It might be just the ticket for sharpening muchos machetes.
Ken
Ken,
Would you post a link to that, please?
Elden,
I'm not too slick with links. Here's a low tech copy paste:
Ken S
Hero Member
Posts: 559
inspired by Ionut and Herman
« on: Yesterday at 10:15:54 pm »
QuoteModify
Back during the time period when Ionut made his small knife blade jig, I posted a couple ideas. One was for a wooden jig, similar to Ionut's. The other was essentially sawing an SVD-110 in half. That would allow a small blade to be held on either side of the wheel, as the table would be about the same width as the wheel.
I purchased a second SVD-110 at the time, and never got around to finish the jig.
Herman inspired me with his jig.
this afternoon I got out the SVD-110s. one had two holes for holding screws. I measured off a line about 1 7/8" from one side and headed toward the bandsaw. My 1/2" 3 tpi blade made short work of the cut through the extruded aluminum. Surprisingly, the cut was almost as smooth as the factory cut.
I knew I would need to turn the jig around to get close enough to the wheel. I had purchased a regular 6mm short bolt to substitute for the Tormek knob.
Alas, the bolt was still too long. I ground down the bolt on the belt grinder. Still too long. I filed down the threaded surface on the jig. Still too long. At this point I am unable to get close enough for a 20 degree bevel.
I have not given up. I will attach something, either wood or metal on top of the jig. It will work in time. For now, I have an SVD-110, an SVD-70 and an SVD-45. (wow!)
still plugging along.....
Ken
Herman,
Another idea came to mind. I have no clue if it's even needed or a good idea, but it's an idea nonetheless. :)
What if your top metal plate was wider than the wheel, so that, with a cutout in the center of the metal plate, tabs on the plate would extend past both sides of the wheel. Like this, viewed from above:
- = metal plate
x = wheel
-----------
-----------
------ xxxxxxx
------ xxxxxxx
-----------
-----------
Drill holes through the tabs, near the ends, so as to insert a post extending upwardly and perpendicular to the plate. The "posts" could simply be a small bolt. Possibly with a piece of loose aluminum tube over the bolt, so that it would rotate freely around the shaft of the bolt.
Why? This would provide a rest for the edge of a knife as it was pulled across the wheel, providing an absolutely steady, even distance from edge to wheel. You might call it the MSS System (Machete Sharpening System).
Everything nowadays needs to be a "system". Or even better... "Now... with MSS Technology!"
Quote from: grepper on March 11, 2013, 08:54:30 PM
Then when you wanted to use it, there would be almost no setup time. Just slide it on, clamp it down and Bob's.... (Doh!... Rob!) your uncle. No messing around with screws and nuts, and it would work with no modification to the scissors rest.
This might be a good idea for a future prototype. Right now it works ok with just the two screws to install. That's a pretty quick set up.
The biggest problem with this jig is going to be rust. It's going to take due diligence to keep it dried and oiled between uses.
Quote from: kb0rvo on March 11, 2013, 09:40:43 PM
Quote from: Herman Trivilino on March 11, 2013, 01:24:18 AM
I can see how this jig may surpass the knife jig for sharpening all knives, not just small ones. One advantage it has is that it keeps the bevel angle constant all the way to the knife tip.
This was what I was referring to in a different post in another thread. I personally like the bevel angle to be the same all the way to the point of the tip. Yes, the width of the bevel grind will become greater on the tip, but remember the tip as it goes out to the point, gets thicker.
I'm not following you. It seems to me, and practice confirms, that the width of the bevel stays uniform. The grindstone should touch the blade in such a way that it's tangent to the blade's curve. If the bevel gets wider the edge angle gets smaller, and my point was that we can avoid that effect with this jig.
Quote from: grepper on March 12, 2013, 01:16:36 AM
Drill holes through the tabs, near the ends, so as to insert a post extending upwardly and perpendicular to the plate. The "posts" could simply be a small bolt. Possibly with a piece of loose aluminum tube over the bolt, so that it would rotate freely around the shaft of the bolt.
Ok, I follow you so far.
QuoteThis would provide a rest for the edge of a knife as it was pulled across the wheel, providing an absolutely steady, even distance from edge to wheel. You might call it the MSS System (Machete Sharpening System).
Would this be the cutting edge of the knife that runs along the wheel? It seems it would have to be positioned just so, and if you changed to a different grinding angle you'd need it in a different position. Maybe I'm not understanding you.
After a trip to the hardware store that bore no fruit for design innovations I came back home and made one more modification to the jig.
(http://i1291.photobucket.com/albums/b553/htrivilino/003_zpsad4a9e81.jpg)
As you can see I trimmed off the excess metal and gave up on countersinking the attachment screws. That tool steel is just too hard and I don't have a drill press. Plus, there's really no need as the screw heads are not in the way.
I sharpened my machete with this jig today and it did a wonderful job!
I also sharpened my precious Buck pocket knife removing almost no steel from the edge. When I look at the bevel with a magnifier I can see that only the slightest amount of steel has been removed.
This jig is a dream to adjust. With the set screw on the scissors jig loose the platform is balanced as it rotates. If I set it on the grindstone it stays there. I can set the angle master on it and rotate the micro adjuster on the universal support until I get the grinding angle just right. Then tighten the set screw on the scissor jig, raise the platform off the grindstone by turning the micro adjus ter just a few degrees, and tighten down the set screws on the universal support.
I will be on the lookout for a scrap piece of flat aluminum in the shape of a rectangle, maybe 3/16" thick and measuring 3" by 5". This would be ideal as it wouldn't rust.
Yes, Herman that would be the idea.
Is that now how the jig works? You set it for a particular angle, and then, with the knife flat against the jig, pass the knife over the wheel?
The "posts" would simply keep an even distance from wheel to the edge of the knife.
Am I misunderstanding how the jig works?
Please forgive me, and keep in mind that not all of my ideas are fully baked.:) Some may not be baked at all! I'm intrigued by the jig, and and am just running ideas by you as I'm interested in your perspective.
Ok. I just saw your latest post. Maybe posts are completely not needed with just a little skill from the operator.
So, it worked great for a machete! How cool is that Herman! Nice job job on chopping it off to match the width of the tool rest.
I take it that when sharpening the machete, you kept it pressed against the tool rest and got a consistent bevel angle?
Quote from: grepper on March 12, 2013, 02:13:45 AM
I take it that when sharpening the machete, you kept it pressed against the tool rest and got a consistent bevel angle?
Yes, same with a pen knife blade, or anything in between. You hold the blade firmly on the top of the platform and slide it down until it touches the grindstone, then you just move it from side to side. You have to try it to believe how well it works.
I can see this replacing the knife jig. It's awesome!
I put a 30
o edge angle on a paring knife, a 40
o edge angle on my Buck pocket knife, and a 50
o edge angle on my machete.
8) Herman, and Ionut. Very cool.
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:
(http://i1291.photobucket.com/albums/b553/htrivilino/003_zpsd487e0a1.jpg)
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.)
(http://i1291.photobucket.com/albums/b553/htrivilino/001_zps6e59c08b.jpg)
And here's a photo showing how nicely this jig allows the curved knife tip to approach the grindstone.
(http://i1291.photobucket.com/albums/b553/htrivilino/002_zps59c6144f.jpg)
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 30o, 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!
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.
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.
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.
(http://i1291.photobucket.com/albums/b553/htrivilino/KnifeJig_zps18d54464.png)
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!
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
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.
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.
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/
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?
Quote from: grepper on March 13, 2013, 11:46:56 PM
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 ...
(http://i1291.photobucket.com/albums/b553/htrivilino/th_TormekKnifeJig_zps9a634f0e.jpg) (http://i1291.photobucket.com/albums/b553/htrivilino/TormekKnifeJig_zps9a634f0e.mp4)
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
Regarding my earlier post as to the advantage of the small knife jig (skj) over the IH jig. I think I've answered my own question. The answer is edge depth control.
Watching Herman's video, you can see the tendency of the blade to slide up/down on the jig. One thing that the skj does well is it mechanically controls the vertical movement of the knife against the wheel, as the skj handle rests against the control bar.
Using the IH jig, vertical control over the movement of the blade is a matter of operator skill. That's how Bob Kramer does it, and of course, if he can do it, it should be a no-brainer for the skilled artisans that frequent this forum.
Outstanding, Herman! Good technical video quality and informative. Your video has all the characteristics of excellent instructional material.
Keep up the good work.
Ken
Quote from: grepper on March 14, 2013, 02:22:31 AM
Q: It's so simple and obvious, why didn't the Tormek engineers make one in the first place?
I think I might know the answer. If customers pay for this jig, they will be disappointed to see it get damaged. And it will get damaged. The metal is so close to the grindstone that it's inevitable that it will make contact. Of course, the damage is inconsequential, it won't hurt the jig. If you make it yourself you recognize it as a sacrificial piece of scrap metal and you have a totally different set of expectations.
I suppose you could fashion a wheel on it that rides on the grindstone, but I don't see how you could make something like that adjustable for different grinding angles.
Thank you, Ionut.
Quote from: ionut on March 14, 2013, 05:55:31 AM
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.
That's an excellent point. I've noticed that with thicker knife blades that are less flexible the handle does make contact with the scissors platform when I'm sharpening the tip. I can get around that by moving the knife to the side, but it's definitely an issue.
This is another reason why the jig should be longer, rather than shorter.
"I think I might know the answer. If customers pay for this jig, they will be disappointed to see it get damaged. And it will get damaged. The metal is so close to the grindstone that it's inevitable that it will make contact. Of course, the damage is inconsequential, it won't hurt the jig."
Herman, one thing I learned while experimenting with the SVD-110 is how easily the extruded aluminum can be filed with a hand file or worked with a belt grinder. I see your point with many users, however, we need to drop the reverent attitude toward the Tormek and look at it as a very useful tool.
Ken
My small knife jig is all worn away trying to sharpen small blades!
Quote from: grepper on March 14, 2013, 02:20:59 PM
Watching Herman's video, you can see the tendency of the blade to slide up/down on the jig.
There is a tendency for the knife to move
down on the jig. That particular knife that I used in the video has rather narrow face on it, especially near the tip. Here's a drawing of the cross section.
(http://i1291.photobucket.com/albums/b553/htrivilino/KnifeCrossSection_zps0f69adf1.png)
The knife therefore has a tendency to rock, especially when I get closer to the tip.
When the knife does move down all that's going to happen is you'll round off the side of the bevel furthest from the edge, so it won't affect the edge.
Quote from: Ken S on March 14, 2013, 02:52:36 PM
Outstanding, Herman! Good technical video quality and informative. Your video has all the characteristics of excellent instructional material.
Thanks, Ken. I did make a few mistakes, but perhaps I'll redo it when I make a better jig. I'm having a trailer hitch installed on my car today. When I go to pick it up and pay for it, I'll ask if I can rummage through their shop's scraps. Maybe I can find a piece of aluminum, or stainless steel.
Quote from: Ken S on March 14, 2013, 05:05:14 PM
Herman, one thing I learned while experimenting with the SVD-110 is how easily the extruded aluminum can be filed with a hand file or worked with a belt grinder. I see your point with many users, however, we need to drop the reverent attitude toward the Tormek and look at it as a very useful tool.
I agree, Ken. I was looking at it from the point of view of Tormek. It may be a marketing issue for them. In their opinion, of course.
Quote from: grepper on March 14, 2013, 05:08:13 PM
My small knife jig is all worn away trying to sharpen small blades!
Your small knife jig consists of a strip of metal that wraps around the part of the knife called the ricasso (yes, I had to Google it).
Did you not encounter any knives with a narrow or missing ricasso? And how did you sharpen those?
Oh No! I've screwed up my termology.
By small knife jig I ment the svm-45 as opposed to the svm-140 long knife jig.
With my mini tin can jig, if the blade did not a ricasso, then it would develop one after several sharpenings!
Quote from: grepper on March 14, 2013, 06:05:39 PM
With my mini tin can jig, if the blade did not a ricasso, then it would develop one after several sharpenings!
There you go, we'll call it the MTC small knife jig. ???
Or, should be called the Ricasso-Maker? 8)
Quote from: Herman Trivilino on March 13, 2013, 01:50:40 AM
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.
It would have a width of 2", a length of about 4",
Herman,
I am working on mine. How long is your metal plate measuring fro the middle of the USB forward?
I am making mine to be its own jig. A piece of 3/8" pipe is just right to slip onto the USB. That will be welded to a piece of 1/8" thick by 2" wide strap. A hole will be drilled and tapped for a locking bolt with a knob in the 3/8" pipe to lock it to the USB. It won't utilize a Torloc type fit. A hillbilly rigging to simulate that may come later. ;)
Quote from: kb0rvo on March 14, 2013, 10:27:58 PM
How long is your metal plate measuring fro the middle of the USB forward?
2-3/8". It's not a critical dimension, anything close to that will work.
QuoteIt won't utilize a Torloc type fit. A hillbilly rigging to simulate that may come later. ;)
You could just flatten out the pipe a bit with your hammer. ;D
Be careful about where you drill the hole in the pipe for the set screw. It needs to be off-center enough to miss the grindstone.
Alternatively you could use a piece of pipe that's only 2" long, drill the hole in the center, and then make the plate long enough that the USB will always be well above the grindstone. With this arrangement you won't have to worry about a knife handle hitting the jig when you're sharpening the knife tip.
Thanks Herman. I am leaving the pipe longer than the strap so it will extend beyond the wheel 1-2". That will be where the set screw is. The pipe is tight enough that it would just barely have space to be flattened. That torlock kind of forms vee.
I got your phone message, Elden. Do you want me to call you back?
Elden, what kind of pipe are you using? I'm guessing black steel.
Herman, your comment about the jig wearing down reminded me of a conversation I had with David Keller, inventor and seller of the excellent Keller jigs. David knew his jigs occasionally ended up on the wrong side of a meeting with a router bit, and suggested a liquid welding type product for field repair. I did that and it works fine. (Your bondo experience, I suspect, is quite similar.)
Ken
Bondo has many applications, Ken. It can fix just about any screw up where appearance doesn't matter or paint will be applied.
Herman, no your post answered my question.
Yes, it is an old piece of black pipe.
My son went to plug the welder in for me and pulled the plug off the electric cord of the welder. I had had him put a new one on it recently. He obviously hadn't tightened the lugs down well enough. So I'm stalled out for the moment as he left for his senior trip. :(
Just as well, Elden. I thought of a modification. In between the pipe and the plate you could weld a scrap piece of metal so there'd be a larger distance between the US and the plate. That way knife handles won't hit the US.
(http://i1291.photobucket.com/albums/b553/htrivilino/EldenJig_zpsbc6c10ce.png)
Last night I was sharpening one of those "Swiss Army Knives", you know, the type with a corkscrew, scissors, frying pan, and just about anything else you can think of all folded into the handle. The handle is so wide it hit the US when I was sharpening the blade tip.
I have to say, though, that this jig is marvelous. The blade on this knife had obviously never been sharpened. With a magnifier I could see the machining marks from the factory still on the surface of the bevel. Also, the blade hadn't suffered any damage, no nicks at all. It was just dull from regular use, plus there was no way it could have been razor sharp from the factory with those machining marks on there.
I used the angle master to measure the angle. It was 35o so I set the jig at 17.5o. Then I put the blade on the jig and measured the angle to the top surface of the blade, it was 22.5o so that means the blade is wedge-shaped with an edge angle of 5o. I readjusted the jig to an angle that was smaller by half that much, or 15o.
If you're having trouble following the math, that's 17.5o - 2.5o.
With the grindstone prepared fine I ground the edge. It took only a couple of passes because I had reproduced the original edge angle so precisely. I removed very little steel from the knife blade and restored it to a keen edge.
The precision of the Tormek is astounding!
Thanks Herman. I hadn't thought of getting into the USB as I thought the handle would be in front of it. I'll plan on a spacer.
I made a wooden version of the small knife jig today.
(http://i1291.photobucket.com/albums/b553/htrivilino/KnifeJigWood1_zps602383c8.jpg)
This is the same as the previous version, and attaches to the base of the scissors jig using the same two screw holes. It has the advantage of being thicker so that the knife handles won't hit the universal tool support.
I've added another feature, which you can see in this view. It's a small brass strip that can by used to index the position of the jig on the scissors base. The intention is that in future versions it might be possible to use only one screw to attach the platform to the scissors jig.
(http://i1291.photobucket.com/albums/b553/htrivilino/KnifeJigWood2_zpsf0e74d76.jpg)
In this photo you get a better view of how the brass plate functions. It hangs below the wooden platform so that it can placed up against the side of the scissors jig base.
(http://i1291.photobucket.com/albums/b553/htrivilino/KnifeJigWood3_zpse2f95320.jpg)
Quote from: kb0rvo on March 15, 2013, 08:26:48 PM
Thanks Herman. I hadn't thought of getting into the USB as I thought the handle would be in front of it. I'll plan on a spacer.
Elden, the handle hits the universal support when sharpening the knife tip, but only if the tip is curved too much, the knife handle is too wide, and the blade is just the right length.
Makes sense. Thanks for the suggestion of the spacer!
You're welcome, Elden. I'd like to see how it turns out. I hope you can show us pictures.
And I'll be particularly interested in hearing about your sharpening experiences with it.
I've run out of dull knives to use on mine! I've sharpened every paring knife and every pocket knife I can find. Plus the only machete I own. Next I plan to try it on a kitchen knife, a knife that you'd normally sharpen using the SVM-45. You know, that "other" knife jig. ;)
Herman, I am curious to know your results sharpening regular kitchen knives with your new jig. Do keep us posted.
Ken
I sharpened a six inch kitchen knife yesterday. It's large enough for the Tormek knife jig, but I used mine anyway.
It had been sharpened to 40o but I wanted to change it to 30o because I'd read somewhere that that was a better angle for kitchen knives, plus I wanted to see if I could get it as sharp as that Victorinox knife I bought a few weeks ago.
I started with the grindstone rough then finished it fine. Polished the bevel on the leather wheel. Success! It cuts through paper as smoothly as the Victorinox. :)
Now, if that Victorinox ever gets dull I'll have a chance to do a real comparison.
Good job, Herman. One knife doesn't tell the whole story, but it certainly raises some questions about interesting possibilities. I can see how your jig might be faster for someone sharpening lot of knives, no resetting for each knife.
Thanks for the post.
Ken
That is one benefit. The other I did the same thing with a pair of pairing knives. I first ground them both with the grindstone coarse because I was changing the bevel angle, then prepared the grindstone fine and finished both. No need to remount them in jigs!
From another thread ...
Quote from: ionut on March 21, 2013, 05:48:14 PM
Herman, I understand you are aluminumizing your small knife jig. I know is too late but another option maybe better one would be to use UHMW polyethylene to build the platform. It is easily workable, does not clog grind stones if you plan use grind it, it is impervious to water and the best part as I see it is the fact that is very low friction, the blades would slide very easily on it. I believe a 3/8" thickness would provide enough rigidity but it can be even thicker.
It's never too late to try a good idea for a prototype. The aluminum I have is not thick enough and is therefore not rigid enough. I was thinking of laminating it to the wooden base, but I like your idea better.
Where could I get the very small quantity I need? I take it this is something not readily available in hardware stores or home centers.
The issue is raising the platform high enough above the base of the scissors jig so that the knife handles don't hit it or the US.
Another issue is, as you mentioned, friction. I found that the wooden surface was just not slippery enough even after waxing and oiling it. I didn't try grease. ;)
Don't forget that in inventing the electric light bulb, he failed with the first over 1000 prototypes. He was known to have said "all I've done is find another way it doesn't work" which means I'm closer to my goal.
What a fabulous attitude to never giving up....I've always really liked that epithet.
Hi Herman,
I know Lee Valley has a pack of small pieces different sizes and thicknesses, you will have to check to see if any of them would fit. Last time I got a bunch of 1/4 " and a much thicker than needed one. If I remember correctly they have bigger pieces sold individually, check their site. There is another company that caries large sheets and different thicknesses of it you can really find it there, It is called Industrial Plastics but I am not sure if you have one close to your place. Unfortunately the hardware stores not only don't carry something like this but if you ask them about it they have no clue what are you talking about, at least that was my experience. Let me know if you can find it close to you anywhere, if not I will stop one day at the store close by and will get a piece for you and send it by mail.
I think a 3/8 thickness would be enough to clear most of the handles but you can always go thicker.
All the best,
Ionut
Could you not switch to tin instead? You could cut up a thin shim of beer can or similar and laminate wood with it. To fix it, superglue would work as long as its the industrial stuff.
Ionut's recommendation of Lee Valley is a very good one. Lee Valley is a very reputable place and has some interesting and unusual things as well as the standard fare. (They often offer special closeouts at very nice prices.) I have been a very satisfied customer for many years. About once a quarter, they advertise free shipping for orders over forty dollars US.
Ken
A note on the length of the jig's platform. As I've stated before, one of the variables involved in the design of this jig is the platform length. If the platform is too short you won't be able to grind at the smaller edge angles desired for some knives or tools. On the other hand, if the platform is too long you'll have the grinding edge too far away from the operator for comfort. So, we want to keep the jig as short as we can and still be able to grind at edge angles as small as, say 10o.
Thickness of the platform is therefore a factor because the thicker the platform, the longer the jig needs to be. And for a jig designed to grind down to angles as small as 10o, every time you add a millimeter of thickness to the platform you have to add nearly 6 mm to it's length.
So we want the platform as thin as we can get it, but not so thin that knife handles hit the US or the scissors jig base. And, as Rob noted, of a sufficiently rigid material so that it doesn't flex.
Is that why aluminium then....rigidity for a thinner substrate than wood?
Quote from: ionut on March 21, 2013, 07:50:43 PM
I think a 3/8 thickness would be enough to clear most of the handles but you can always go thicker.
I think that would be about right, Ionut. Thanks for your offer. I'll ask around and see where I can go to buy some. I live and work in the greater Houston area, which is a major industrial area. The stuff's got to be around here somewhere.
Quote from: Rob on March 21, 2013, 08:38:27 PM
Could you not switch to tin instead? You could cut up a thin shim of beer can or similar and laminate wood with it. To fix it, superglue would work as long as its the industrial stuff.
Uhhh ... Rob, I believe that even on your side of the pond they make beer cans out of aluminum! The aluminum I have is about 1/8" thick. But if you could find a way to successfully laminate a thinner piece to the wood you wouldn't have to worry about grinding the bevel on the aluminum.
Quote from: Rob on March 21, 2013, 09:17:20 PM
Is that why aluminium then....rigidity for a thinner substrate than wood?
Well, that would be a factor, but I hadn't considered it. The problem with wood is it's not very slippery and it's not water proof. If I could get a slab of aluminum about 3/8" or 1/2" I'd be very happy. So, availability of materials is another factor.
Ionut's idea for the material is a good one.
Ah got it....metal because of water resistance and slippery
Congrats Hero Herman :-)
You and Ken will be giving Jeff a run on the post count soon.
What's after hero......galaxy class?
Hi Herman,
The length and thickness become an issue in relation to the allowed angles and clearances, when the small platform is being fixed on the Tormek jig.
If clamping it doesn't give you the clearance or you want a more definitive solution that would allow you more flexibility I would suggest routing at the place where your bolts are , two lengthwise slots right through the platform, one with a ½ " bit and one with ¼ bit. The ½ one would be probably only 1/8 deep but the ¼ one would go all through the platform in the center of the first one. That would allow you to use T-slot screws that would be flush with the upper surface of the platform, and you could have underneath some wing nuts or anything similar and you will be able to move the platform closer or further away from the stone depending on what you want to achieve. I believe 2" long slots would give you enough adjustment for almost anything you want. Before getting the UMHW you could try to experiment with the wooden version, before you commit for a definitive solution and se what is fitting your needs better.
Ionut
I have my rough version mostly done . Welded the spacer block to the 3/8" pipe, bolted the plate to the spacer block with countersunk screws. Drilled and countersunk 2 extra sets of holes so that the plate extension length can be changed.
Congratulations Herman!
Sometimes a person can get thick scrap plexiglass at places that handle glass. I got a piece of 1/4" free from a lumber/farm supply store.
Can you post pictures Elden?
Not yet, but am working on it.
What's the problem?
Quote from: Rob on March 21, 2013, 09:30:20 PM
What's after hero......galaxy class?
Why, super hero, of course.
Thanks everyone!
Quote from: ionut on March 21, 2013, 10:02:14 PM
If clamping it doesn't give you the clearance or you want a more definitive solution that would allow you more flexibility I would suggest routing at the place where your bolts are , two lengthwise slots right through the platform, one with a ½ " bit and one with ¼ bit.
Good ideas, Ionut. I think clamping gives me all the flexibility I'll need.
I did some whittling on the wooden platform tonight in preparation for the next prototype. I plan to make a more refined version tomorrow and will post pictures. This wooden version could then be used as a model for the plastic version.
Does anyone see a need for grinding bevel angles smaller than 10
o? On a typical knife this would give an edge angle of 20
o.
In Ron Hock's book he says "For tough chopping [...] an included edge angle as large as 50
o or 60
o may be needed, while the slicing of fish or vegetables may call for an edge angle as small as 10
o."
This would be a bevel angle of 5
o unless that's expressed poorly and he's referring to a bevel angle of 10
o.
Especially confusing because he goes on to say that a good kitchen will have a variety of knives ground at different angles for different purposes, but then on the next page he states that the angle for a kitchen knife is "rarely critical".
A good illustration of the need for different blade angles in a kitchen is the recent post about the knife missing a large hunk of the blade due to using it to cut a lobster. (The choice of knife might have been done more carefully as well.)
A Sawzall blade which routinely had to cut through nails as well as wood would be a poor choice for cutting dovetails. Likewise a dovetail saw would be easily destroyed by a nail infested 2x4.
My Chinese cleaver used for slicing vegetables can and should be sharpened to a different angle than the heavier chopping cleaver of a more carnivorous person. Vegetables are boneless.
A paring chisel should be ground to a finer bevel than a dovetail or mortising chisel which is hit with a mallet.
Is the exact angle critical? I think we live in a world of tolerance ranges. If I needed a chisel for paring in a size that I only had one sharpened for dovetail chopping, I would use it. Being very sharp covers a multitude of sins. It might not be the ideal tool, but it would work.
One of the joys of skillful sharpening is the ability to adapt edges to specific uses. We can grind a knife or chisel specifically for very light, intricate paring. We can grind the same tool for more utilitarian use. A good chef or woodworker would want that flexibility.
I believe a "compleat" sharpener also uses the edges he creates and maintains. Whether the blade is a chef's knife, chisel or for a lawn mower, the person who sharpens that blade should have a working knowledge of how the tool behaves under different degrees of sharpness. The true test of a sharp kitchen knife is on the cutting board, cutting whatever the intended use is.
I am one of the forum who regularly proclaims the value of being able to sharpen a simple chisel edge. That is an important foundation block in sharpening. I would not minimize it. However, once the basics become solid, there is a whole range of options to adapt the tool to the job and the individual worker. I believe both the satisfaction of doing basic work well and the creativity of choices add to the satisfaction of the sharpener.
Ken
Gentlemen
I've just this morning posted a new topic which addresses some of the ambiguity and confusion in this area.
It finishes with a table which we could all evolve until we have a definitive list of bevel/included angles for blades aimed at a specific job. A quick reference if you like to save us having to wade back through all the knowledge references. I plan to keep mine taped to the Tormek when complete
Herman I would like to know the physical dimensions of the plate.
My current sharpening project is my Japanese Kitchen Knives which use an angle of 10-15 degrees depending on the knife and the cutting application.
I followed your post and also watched your video as well.
I have the three current grinding wheels.
The jig you have devised seems to meet my requirements however it would be better if I had physical dimensions and a simple procedure to set the correct grinding angle.
Thanks for your effort and posting to encourage people like myself.
Quote from: Herman Trivilino on March 10, 2013, 09:28:19 PM
This worked great. I had perfect control.
(http://i1291.photobucket.com/albums/b553/htrivilino/002_zpsd672a4fb.jpg)
Herman While I agree with you on the lifting of the blade, I do not like working over the rotating wheel.
To many mistakes can be made when any part of the body is over the top of any rotating device no matter how slowly it is turning.
I am currently working on a Reverse Jig Plate which will allow the Universal Support to be held on the back side of the machine.
This is necessitated for the use in sharpening my Metal Lathe Tool Bits.
Once I learn how to post pictures it will be much easier to explain, I am sure
I am quite late commenting on this thread but:
There are two key features to a jig of this type:
1. It is only as wide as the wheel so you can grind up to the bolster on either side.
2. You grind into the edge so your pressure opposes the grinder pressure.
Almost all tool rests including Tormek's are too wide for rule 1. If you cut them to the proper width you discover A: the tongue is too short, or if you turn it around, B: the Knob is in the wrong position. I suggested the correct design to Torgny years ago but it never made it off his desk.
If you ignore rule 2. the wheel will lift the blade off the guide and pull it away from you.
Quote from: stevebot on June 09, 2015, 02:59:43 PM
I am quite late commenting on this thread but:
There are two key features to a jig of this type:
1. It is only as wide as the wheel so you can grind up to the bolster on either side.
I discovered that myself. It also helps if the jig is thick enough so that the bolster doesn't hit the universal support rod when sharpening curved tips of shorter knives. About 12 mm seems to do the trick.
Quote2. You grind into the edge so your pressure opposes the grinder pressure.
Almost all tool rests including Tormek's are too wide for rule 1. If you cut them to the proper width you discover A: the tongue is too short, or if you turn it around, B: the Knob is in the wrong position. I suggested the correct design to Torgny years ago but it never made it off his desk.
Page 18 of the Tormek Handbook (which can be downloaded for free once you register at http://tormek.com/international/en/account/register/) explains perhaps why Tormek hasn't developed a tool rest like our homemade version.
QuoteTool Rests and Grinding Jigs
To achieve an even and sharp edge, the tool must be held steadily and with a consistent
grinding angle to the wheel. This is obtained by resting the tool on a tool rest or clamping
it in a grinding jig.
A common tool rest on fast running bench grinders is a bent plate which is usually too short
to support the tool properly. This simple tool rest can be replaced by a larger and more sturdy
support to enable you to hold the tool steadily towards the grinding wheel. The tool rest can
also have a fence which is guided in a slot, so you can keep the tool at 90° or at a specific
skew angle to the grinding wheel.
These type of tool rests have been developed for high speed grinders, where you work with a
low grinding pressure due to the high rpm. However when mounted on a water-cooled grinder
which requires a higher grinding pressure, they do not work satisfactorily. This is because
the pressure which you apply to the tool does not reach the grinding spot but instead goes
to the tool rest. (Picture no 1).
To obtain the required grinding pressure, you also need to push the tool from the handle direction
towards the wheel. Then the tool tends to climb up on the grindstone and the precision
is lost. (Picture no 2). You need to push the tool both towards the wheel and downwards so
that it does not lose its contact with the tool rest. In practice this is not possible.
This effect appears when grinding narrow edge angles and when grinding both towards and
away from the edge. The disadvantage is more severe when grinding turning tools, as they
are often made of HSS-steel which is hard and requires a high grinding pressure.
For turning scrapers which are ground at larger edge angles, this type of tool rest works
satisfactorily on dry or water-cooled grinders. The reason that these types of tool rest work
fairly well on high speed dry-grinders, is that they require a lower grinding pressure and
therefore the disadvantages can be overcome.
I have discovered, though, that lots of pressure (actually force is the more correct term here) is not needed when sharpening knives. Unlike an axe or perhaps a chisel or other tool, when sharpening a knife it's not necessary to remove lots of steel. Perhaps Torgny won't budge from what he considers a basic design principle of his Tormek.
Regardless of all that verbiage and complication, Herman's simple tool rest is quick and easy to use tool to have in the arsenal that extends the usefulness of the machine to a wider array of sharpening applications. A machete is a good example.
Mark, verbiage and complication make the world go round. ;D
On a more useful note, I think someone making one of Herman's HK-50s (or HK-40s) would be wise to make a jig for drilling the holes accurately into the platform. I believe Herman's jig has many uses beyond small knives (and machetes). By using a hole jig, future platforms could easily be interchanged with the original, the raised secondary platform for short chisels being an example. I can envision someone having half a dozen interchangeable platforms for the scissors jig platform.
Ken
Two other things that are somewhat obvious:
3: the tongue must be long enough to permit low angles, preferably 10 or 12 degrees
4: the knob must be on the right side to be accessibility.
Home improvement stores carry 2" x 1/4" Al stock that makes a nice tongue.
Quote from: Ken S on June 09, 2015, 05:23:27 PM
By using a hole jig, future platforms could easily be interchanged with the original, the raised secondary platform for short chisels being an example.
The scissors jig base makes a perfectly good jig for drilling holes in newly made platforms. Just use the threaded holes in the scissors base to guide a much smaller drill bit into the new platform, making pilot holes. Then you can widen the pilot holes to the desired diameter.
Quote from: grepper on June 09, 2015, 04:48:30 PM
Regardless of all that verbiage and complication, Herman's simple tool rest is quick and easy to use tool to have in the arsenal that extends the usefulness of the machine to a wider array of sharpening applications. A machete is a good example.
I agree, Mark. I use mine to sharpen a variety of items, but my favorite is still the knives I use every day. Pocket knives and kitchen knives. It's just so much easier to set the edge angle and go. If I have several knives to sharpen, all at the same edge angle, I don't have to adjust the jig in between knives.
This is a topic which needs to be kept readily available. The small platform is a very useful, versatile tool. I think every serious Tormek sharpener, especially knife sharpeners, should make one. I have never understood why Tormek does not make one.
Ken
Quote from: Ken S on September 04, 2020, 05:32:32 PM
This is a topic which needs to be kept readily available. The small platform is a very useful, versatile tool. I think every serious Tormek sharpener, especially knife sharpeners, should make one. I have never understood why Tormek does not make one.
Ken
Pin it to the top! ;)
Great idea, CB.
Done!
Ken
If anyone is looking for reasonably priced Aluminium flat bar I have just purchased 2" wide by 1" thick and 200mm long from ebay for £13.40 with free delivery, they dont seem to do free for everywhere and the auction suggests they only deliver to local addresses but I just messaged them, (its 23.40) and they got back to me straight away saying my postcode is free delivery and Im in Reading. Ok this is one for UK members only. https://www.ebay.co.uk/itm/201367237820
Alan,
For the "diving board" part of the small platform, 1/8" is plenty thick. I suggest mounting the diving board on the scissors jig platform. As shown in this video, the scissors jig platform has Tormek's patented Torlock, which holds the platform much more securely.
https://advanced-machinery.myshopify.com/products/svx-150-scissors-jig
Ken
topic pinned in error
Ken
Quote from: Ken S on September 16, 2020, 02:33:25 AM
Alan,
For the "diving board" part of the small platform, 1/8" is plenty thick. I suggest mounting the diving board on the scissors jig platform. As shown in this video, the scissors jig platform has Tormek's patented Torlock, which holds the platform much more securely.
https://advanced-machinery.myshopify.com/products/svx-150-scissors-jig
Ken
Thanks Ken, I have the scissor Jig, I went for 1" because of my Leathermans, they have a 3/4" step which I thought would hit jig. I took the blade out of the last one I did against there recommendation and it was a bloody PITA to get it all back together, it was worth it but i blunted it the next day cutting wire wool so im looking for a faster option....