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In the Shop => General Tormek Questions => Topic started by: Herman Trivilino on March 23, 2013, 05:21:35 am

Title: Homemade Knife Rest (HK-50)
Post by: Herman Trivilino on March 23, 2013, 05:21:35 am
I've been working on this jig for a couple of weeks now.  The original thread is here:
http://www.tormek.com/forum/index.php?topic=1560.0

I'm starting a new thread in honor of the new name I've come up with for this jig.

I'm calling it the Homemade Knife Rest (HK-50).

This is a platform for supporting knife blades.  It sits atop, and is attached to, the base of the Tormek Scissors Jig (SVX-150).  The end of the platform nearly touches the grindstone so that the edges of knife blades of all sizes, from small pen knives to large machetes, can be ground.


Title: Re: Homemade Knife Rest (HK-50)
Post by: Herman Trivilino on March 23, 2013, 05:36:59 am
To make the platform I started with a piece of hardwood about 13 mm (0.5") thick and a bit wider than the finished width of 50 mm (2"), which is equal to the width of the Tormek grindstone.  I cut off a length of about 250 mm (10") which is a piece long enough for two of these platforms.  (If it were only long enough for one platform it'd be too short to hold onto while working it into its final shape.) 

The first step is to cut that curved bevel that sits just a millimeter or two off the surface of the grindstone.  I cut one on each end of the piece by nibbling away on my 10-inch table saw blade.


Title: Re: Homemade Knife Rest (HK-50)
Post by: Herman Trivilino on March 23, 2013, 05:38:51 am
Here I'm using a chisel to clean up between the nibbles on the curved bevel.


Title: Re: Homemade Knife Rest (HK-50)
Post by: Herman Trivilino on March 23, 2013, 05:40:33 am
Sanding after chiseling.
Title: Re: Homemade Knife Rest (HK-50)
Post by: Herman Trivilino on March 23, 2013, 05:42:45 am
Ready to be cut in half to make two platforms.
Title: Re: Homemade Knife Rest (HK-50)
Post by: Herman Trivilino on March 23, 2013, 05:43:05 am
delete
Title: Re: Homemade Knife Rest (HK-50)
Post by: Herman Trivilino on March 23, 2013, 05:46:24 am
Here the final fitting of the curved bevel is done.  The grindstone itself is used to grind the wood.  The high spots where the wood touches the grindstone are easy to see because the residual moisture in the stone is wicked up into the wood.  These high spots can then be sanded down with sandpaper.


Title: Re: Homemade Knife Rest (HK-50)
Post by: Herman Trivilino on March 23, 2013, 05:52:03 am
Here you can see that the bevel angle is about 10o.  You can also see how close a knife blade will be able to get to the grindstone.  The wood is still perhaps a bit too thick at the very end of the bevel.  It's actually a bit thinner on the other one.  The thinner you get it the closer you can get to the grindstone.  However, make it too thin and it won't be rigid enough to stand up to the pressure applied by the operator when sharpening a knife.

Title: Re: Homemade Knife Rest (HK-50)
Post by: Herman Trivilino on March 23, 2013, 05:55:51 am
Here it's been lifted to a 15o bevel angle.  For angles this large and larger, when you go to sharpen a knife you'll be able rest a larger portion of the blade on the platform and the thickness at the end of the bevel is no longer a critical issue.


Title: Re: Homemade Knife Rest (HK-50)
Post by: Herman Trivilino on March 23, 2013, 05:58:55 am
Here are the two finished platforms.
Title: Re: Homemade Knife Rest (HK-50)
Post by: Herman Trivilino on March 23, 2013, 06:10:42 am
Perhaps tomorrow I'll make a couple more!

I recommend starting with a piece of wood that's a good bit wider than the finished width of 50 mm (1-31/32").  When nibbling away to make the curved bevel you're likely to get some tear-out at the sides.  Also, don't try to make the narrow end of the bevel too narrow by raising the table saw blade too high.  It gets quite flimsy and the table saw blade will knock out chunks of it.  If this happens just trim a bit off the end, that's why it's best to also start with a piece of wood that's a good bit longer than needed.
Title: Re: Homemade Knife Rest (HK-50)
Post by: Ken S on March 23, 2013, 10:20:51 am
Well done, Herman.

Ken
Title: Re: Homemade Knife Rest (HK-50)
Post by: Rob on March 23, 2013, 12:30:10 pm
Excellent Herman

And thanks for all the pics, they really make a difference.
Title: Re: Homemade Knife Rest (HK-50)
Post by: jeffs55 on March 23, 2013, 03:35:32 pm
First off, good job. Now, I see you are using the scissors jig with the tool bar in the vertical position. Is this because of an inability to get the proper angle in the horizontal plane? It looks like you could just cut the jig in half across the plane of the jig to include the mounting hole of course and reduce its width to allow control on a small blade such as you picture. I mean to mount the jig horizontally and adjust the angle to the desired bevel and go to it. All this assumes that you can get the jig close enough which I am sure you could. The angle you would need is the question here as I cannot test this theory. I have not tried this and do not have a scissors jig. It looks like the tool rest SVD 110 would work and is cheaper than buying the scissors jig. Also, as an aside; I see a possible use of the square edge jig with a piece of stiff metal mounted in it to replace the wooden guide you have made. Imagine a chisel or go and get one. Mount it in the square edge tool and see if you can place your pen knife in it in such a way to allow you to sharpen it. They don't lock on the tool rod but does it need to lock?  I think UKR is a better name or UKR-13. In my naming protocol the "13" is for the year 2013 and UKR is for "universal knife rest" as you suggest it can be used on anything from pen knives to machetes. What does the "50" represent? Finally, your presentation is so well illustrated that even I could make one, good job!
Title: Re: Homemade Knife Rest (HK-50)
Post by: Rob on March 23, 2013, 04:40:22 pm
50 I think refers to 50mm wide ie 2inch ie just a hair wider than the grindstone.

I think that idea of using wide chisel in the square edge jig as a makeshift base is another good idea. Just thinking out loud though....the torlok rest can get right up close to the grindstone...why couldn't you just use that directly instead of any additional piece?
Title: Re: Homemade Knife Rest (HK-50)
Post by: Rob on March 23, 2013, 04:40:58 pm
The angle would be too steep right?
Title: Re: Homemade Knife Rest (HK-50)
Post by: Herman Trivilino on March 23, 2013, 05:11:01 pm
First off, good job.

Thanks Jeff, and everyone else, for the compliments.

Quote
Now, I see you are using the scissors jig with the tool bar in the vertical position. Is this because of an inability to get the proper angle in the horizontal plane?

With earlier prototypes I did experiment with the US in the horizontal position.  With the grindstone turning away from the grinding edge it kept lifting the knife blade off the platform.  It's much easier to control the operation with the US in the vertical position so that the grindstone turns toward the edge, pinning the knife blade to the platform.

Quote
It looks like you could just cut the jig in half across the plane of the jig to include the mounting hole of course and reduce its width to allow control on a small blade such as you picture.

The locking screw hits the US when you do that.

Quote
It looks like the tool rest SVD 110 would work and is cheaper than buying the scissors jig.

You can purchase the scissors jig base separately at a lower cost than the tool rest.  I'm not sure if the SVD-110 would work better, I don't own one.   :(

Quote
Also, as an aside; I see a possible use of the square edge jig with a piece of stiff metal mounted in it to replace the wooden guide you have made. Imagine a chisel or go and get one. Mount it in the square edge tool and see if you can place your pen knife in it in such a way to allow you to sharpen it. They don't lock on the tool rod but does it need to lock? 


Yes, it very much does need to lock, but you have a good idea.  I don't own the square edge jig.  I have its predecessor, the straight edge jig SVM-60, but I think it might work.  I mounted one up.  You could drill and tap a hole for a locking screw, but you'd lack the Torlock feature.  Plus, when sharpening knife tips with large curvatures the knife blade or handle might hit the jig, which might be a bother.

(http://i1291.photobucket.com/albums/b553/htrivilino/001_zps9c4cd532.jpg)

Quote
I think UKR is a better name or UKR-13. In my naming protocol the "13" is for the year 013 and UKR is for "universal knife rest" as you suggest it can be used on anything from pen knives to machetes. What does the "50" represent?

As Ken told me yesterday, the numbers are the jig width in millimeters.  I chose HK-50 to be consistent with the other jig names.  Also, if you look at the tool rest jig they gave it a model number of SVD-110, not TRJ-110.

Quote
Finally, your presentation is so well illustrated that even I could make one, good job!

Thanks. It was probably just as much work to document the process as it was to make the jig.  But it's a necessary part of the process as without meaningful communication we'd not make progress with improvements and modifications
Title: Re: Homemade Knife Rest (HK-50)
Post by: Herman Trivilino on March 23, 2013, 05:19:23 pm
50 I think refers to 50mm wide ie 2inch ie just a hair wider than the grindstone.

The grindstone has a width of precisely 50 mm (1-31/32").  That's the jig width, just a fuzz under 2"  Well, for a first-fix carpenter that's a fuzz!   ;)

Quote
Just thinking out loud though....the torlok rest can get right up close to the grindstone...why couldn't you just use that directly instead of any additional piece?

I don't have the Tool Rest (SVD-110) but I don't believe it gets close enough to the grindstone.  Ken S was working on this issue.
Title: Re: Homemade Knife Rest (HK-50)
Post by: Elden on March 23, 2013, 05:28:55 pm
Very well done Herman! Interesting that your angle master will pivot that far. Mine stops at 16 degrees, it won't quite make it to 15 degrees.
My son was took some pictures yesterday and will be e-mailing them to me. So hopefully will get them posted soon.
Now off to try to dig out the pixel quality that was advised for posting pictures. :)
Title: Re: Homemade Knife Rest (HK-50)
Post by: Elden on March 23, 2013, 08:52:48 pm
Off the top of my head ( ;)), it sounds like the square edge jig with a chisel in it, would work up to a point. It would restrict how far the handle could be swung towards the operator to get the tip sharpened. The top portion of the jig would be above the level of the chisel (effectively your table). This would come into play on larger knives (machetes) for sure.
Title: Re: Homemade Knife Rest (HK-50)
Post by: Herman Trivilino on March 23, 2013, 09:06:24 pm
Very well done Herman! Interesting that your angle master will pivot that far. Mine stops at 16 degrees, it won't quite make it to 15 degrees.

Thanks, Elden.  My angle master is from 2002.  I wore the end that touches the grindstone to the point that it was no longer useful (most of this wear came during the first few weeks of use as I fumbled about).  So, a few weeks ago I ordered a replacement of just that part.  It has a different shape, and the curved groove extends further.  I suppose if I were to buy a new angle master I'd see more differences.  It's awesome that the Sharp Tools USA website shows an exploded view of every jig, so you can buy any little part you want.

Quote
My son was took some pictures yesterday and will be e-mailing them to me. So hopefully will get them posted soon.
Now off to try to dig out the pixel quality that was advised for posting pictures. :)

I open up the pictures I take with my cell phone into Microsoft Paint.  I then reduce them to 40% of their original size, save them, and then upload them to Photobucket.  They seem to be about the right size when I visit this site and look at them.  They are not so large that they extend past the edges my computer screen, and they are large enough to show the details.
Title: Re: Homemade Knife Rest (HK-50)
Post by: Herman Trivilino on March 23, 2013, 09:09:02 pm
Off the top of my head ( ;)), it sounds like the square edge jig with a chisel in it, would work up to a point. It would restrict how far the handle could be swung towards the operator to get the tip sharpened. The top portion of the jig would be above the level of the chisel (effectively your table). This would come into play on larger knives (machetes) for sure.

Plus, you can't lock down the square edge jig so that it doesn't rotate about the US, can you?  That would be a deal-breaker.
Title: Re: Homemade Knife Rest (HK-50)
Post by: Elden on March 23, 2013, 09:18:26 pm
True. I hadn't thought that far. Someway, I missed the 2nd page of posts before posting my comments. As you showed, that could be fixed. But to me, not having the swing space would nix it.
Title: Re: Homemade Knife Rest (HK-50)
Post by: Rob on March 23, 2013, 09:33:45 pm
If you plan to upload pics to photobucket as the hosting site prior to linking them here, you may also find it useful to know that pb has an editor that allows the size reduction you might need
Title: Re: Homemade Knife Rest (HK-50)
Post by: Elden on March 23, 2013, 09:48:41 pm
Thanks Rob. I found that out when looking back on your thread on picture posting. My problem has been getting the pictures on the computer due to the lack of proper software on the computer and the lack of hardware in the phone for transferring.
Title: Re: Homemade Knife Rest (HK-50)
Post by: Rob on March 23, 2013, 09:52:44 pm
What pc is it? Ie which version of windows?
Title: Re: Homemade Knife Rest (HK-50)
Post by: Elden on March 23, 2013, 09:56:43 pm
Mac. But they tell me I have to have a memory card for the phone to be able to transfer.
Title: Re: Homemade Knife Rest (HK-50)
Post by: Rob on March 23, 2013, 10:03:33 pm
Right. I've never owned a mac so can't help there...sorry
Title: Re: Homemade Knife Rest (HK-50)
Post by: Herman Trivilino on March 25, 2013, 06:23:55 pm
Here's a drawing of the latest prototype ...

(http://i1291.photobucket.com/albums/b553/htrivilino/HK-50HomemadeKnifeRest_zpsc2af3a39.jpg)

Note: New version uploaded 7 Apr 2013.  The original contained an error.
Title: Re: Homemade Knife Rest (HK-50)
Post by: Ken S on March 25, 2013, 07:27:20 pm
"Yes, it very much does need to lock, but you have a good idea.  I don't own the square edge jig.  I have its predecessor, the straight edge jig SVM-60, but I think it might work.  I mounted one up.  You could drill and tap a hole for a locking screw, but you'd lack the Torlock feature.  Plus, when sharpening knife tips with large curvatures the knife blade or handle might hit the jig, which might be a bother."

Herman, you are onto something.  For those of us who happen to have the older square edge jig, I think your latest idea is definitely the most direct way to go.

For those with the newer SE-76, it can be made to work, also.  The answer is not quite as simple and direct as the threaded hole for the bolt to keep the jig from rotating.  Two ways come to mind:

1) Use the micro adjust nut to hold up the SE-76.  This won't quite work alone, but a larger nut like Herman's home made device will hold the SE-76 from rotating into the wheel.  The same function could also be done with a short piece of plastic pipe inserted between the usb and the micro adjust nut.  The pipe might require some extra thickness to support th SE-76. A plastic pipe fitting or a larger diameter piece of pipe glued onto the original pipe.

2) the locking collar supplied with the SE-76 could be slipped on to the usb before the jig.  When locked in the proper spot, it would support the jig at the correct angle.

Neither of these methods would secure the jig as well as using the older jig. However, the only direction it could rotate would be away from the wheel, so no harm, no foul. neither of these ways would interfere with the normal function of the SE-76.

My compliments on a solid and simple solution, Herman.

Ken

Title: Re: Homemade Knife Rest (HK-50)
Post by: Herman Trivilino on March 25, 2013, 08:11:24 pm
Ken, the bracket for the original truing tool might be able to work to keep the platform from rotating downward, too.
Title: Re: Homemade Knife Rest (HK-50)
Post by: Herman Trivilino on April 01, 2013, 03:16:16 am
I was cleaning out the corner of the garage where all the scraps are piled up, and I found a sheet of plastic I'd forgotten I had.  I found it a few years ago in a pile of discarded building materials.  It has a thickness of 5/16" (8 mm).  The sheet is 48 3/8" (123 mm) wide, and I don't know what the length is because the piece I have is a cut off.  It has a protective sheet of paper glued on one side. 

So, I went out and bought a cheap plywood blade for my table saw (I'm not about to cut plastic with my good carbide tipped blade!).  The stuff cuts okay, and sands and drills well.  It also has very good rigidity and doesn't flex at the thin end like wood and aluminum does.  Anybody have any idea what this stuff is or what it's used for?

I used it to make the latest version of the HK-50.

(http://i1291.photobucket.com/albums/b553/htrivilino/001_zps5f8344d9.jpg)

I added a new feature, which is a small piece glued to the end used to index the platform so it's square to the scissors jig base.

In this photo the platform is set up to grind at a 10o bevel angle, which is about as small as it can go.

 
Title: Re: Homemade Knife Rest (HK-50)
Post by: Mike Fairleigh on April 01, 2013, 03:49:15 am
It's hard to say for sure what it is from the picture, but it could be UHMW plastic (ultra-high molecular weight).  That's what they use in cutting boards, fence faces, and all kinds of things that need to be somewhat slippery and wear resistant.
Title: Re: Homemade Knife Rest (HK-50)
Post by: Herman Trivilino on April 01, 2013, 07:21:17 am
If it is, I've got about $500 worth of the stuff!

On second thought, that protective paper cover on one side may have a different purpose.  When I removed it it left behind a sticky residue on the plastic.  Maybe it's an adhesive.

I just conducted an experiment.  This stuff doesn't float in water!  We have a plastic cutting board and it does float in water. 

This sheet of plastic is about 4 ft by 4 ft and has been sitting in my garage for years.  I could make a lot of HK-50 jigs out of this stuff.

Right now I have no way of using this jig because with all of the jig-building and testing I've done in the last few weeks every knife in the house is sharp.  Maybe I should go calling on the neighbors.

 
Title: Re: Homemade Knife Rest (HK-50)
Post by: Elden on April 01, 2013, 06:43:41 pm
Jeff shows you how to dull an edge on his chisel video!  ;)  I suppose if you want to be a little less violent, try shaving the grit off some sandpaper or emory cloth. Maybe cut that piece of steak while it's in your iron skillet. ;D
Title: Re: Homemade Knife Rest (HK-50)
Post by: Herman Trivilino on April 09, 2013, 01:55:19 pm
One shortcoming of this jig is that the platform scratches the sides of the knives.  I didn't notice this until I started using the plastic platform.  Maybe other materials will not scratch so badly.
Title: Re: Homemade Knife Rest (HK-50)
Post by: jeffs55 on April 09, 2013, 06:12:33 pm
Is there any reason that the Torlok attachment cannot be used or any advantage to the scissors jig especially if you already have the Torlok? thanx
Title: Re: Homemade Knife Rest (HK-50)
Post by: Herman Trivilino on April 10, 2013, 01:56:49 am
I don't own the Torlock jig so I can't say.  It has been tried but as I recall there were issues that weren't resolved.
Title: Re: Homemade Knife Rest (HK-50)
Post by: Ken S on April 10, 2013, 02:41:25 am
The Torlock should work. It is essentially a different shaped platform than the scissors jig.  I found it, like the scissors jig, needs a secondary platform. It never occurred to me to use the scissors jig platform until Herman posted it.  Either should work.

I have an idea which might possibly work to use the Torlock with no secondary platform.  It involves cutting my second Torlock.  (The first project didn't work on its own with no secondary platform.)  At this point I haven't decided whether to cut up the second jig or make a secondary platform.  I may wait until I have a lot of small blades to sharpen.

Ken
Title: Re: Homemade Knife Rest (HK-50)
Post by: Herman Trivilino on April 10, 2013, 02:51:17 am
One shortcoming of this jig is that the platform scratches the sides of the knives.  I didn't notice this until I started using the plastic platform.  Maybe other materials will not scratch so badly.

I tried a wooden version of the HK-50 that I had applied lacquer to about a week or two ago so it's thoroughly hardened.  It left scratches.  I'm thinking maybe some adhesive-backed felt applied to the top of the platform might be worth a try.
Title: Re: Homemade Knife Rest (HK-50)
Post by: Elden on April 12, 2013, 07:43:46 am
Herman, have you tried the felt?
Title: Re: Homemade Knife Rest (HK-50)
Post by: Herman Trivilino on April 12, 2013, 03:40:24 pm
Not yet, Elden.  The felt I found at Lowe's is way too thick.  Got to look elsewhere.
Title: Re: Homemade Knife Rest (HK-50)
Post by: Herman Trivilino on April 13, 2013, 03:40:28 am
Someone saw my YouTube video and wants to know if I sell these jigs!
Title: Re: Homemade Knife Rest (HK-50)
Post by: Rob on April 13, 2013, 11:20:08 am
Someone saw my YouTube video and wants to know if I sell these jigs!

What did I say!!!
Title: Re: Homemade Knife Rest (HK-50)
Post by: Elden on April 14, 2013, 04:34:43 am
Herman,

I did ask Kurt about the HK-50. I told him that I would try to leave him alone for a while after this question. :)

Hello Elden
I have not used any jig like the HK-50, but my opinion is that if the jig works as expected then it is ok and it does not matter what it looks like or who constructed it.
Feel free to construct or invent whatever jigs you think you need, for example I have made an addition to the Tormek for grinding cabinet scrapers. Many years ago I made a jig for holding my chip-carving knifes, it is just a piece of 6mm plywood that at one end can be attached on to the toolrest  and the other end has a small hook to hold the knifeblade.
Kurt Johansson
Title: Re: Homemade Knife Rest (HK-50)
Post by: Herman Trivilino on April 14, 2013, 05:41:22 am
Good to know, Elden.  I would have thought that someone would have thought of this before and he'd have seen it.
Title: Re: Homemade Knife Rest (HK-50)
Post by: Jeff Farris on April 15, 2013, 05:47:17 pm
While Tormek applauds the innovation shown in developing this idea, this forum cannot be used to sell products, and giving the invention a Tormek-like part number is a bit misleading. I've deleted a few posts in some other threads that mentioned sales of this device. At this point, no harm, no foul, but let's keep this thread moving in the direction of a suggestion for a shop project rather than an offer to buy or sell something.

Let's also be careful in comparing what this idea can do versus any old or new Tormek product. There's always more than one way to approach a problem, and generally no one or the other can be declared perfect.
Title: Re: Homemade Knife Rest (HK-50)
Post by: Rob on April 15, 2013, 07:08:44 pm
Hi Jeff, hope you're well.

I understand your point about no commercial messages being permissible, that's normal forum policy and given its your BBQ entirely reasonable.

I'm less sure about the suggestion of censoring discussion about the pros and cons of different jig approaches to sharpening problems.  Isn't that just open dialogue about problem solving?

One of the things I really value about this forum is its open honest culture.  You really don't micro manage the message and I like that.

Title: Re: Homemade Knife Rest (HK-50)
Post by: Herman Trivilino on April 15, 2013, 07:26:29 pm
Note Jeff said to be "careful" about the comparisons, he didn't say to stop them and he didn't delete posts where these comparisons were made.

There are advantages to the homemade knife rest, or perhaps it would be better to refer to it as a zero-clearance jig, or perhaps a mini-clearance jig.  There are also disadvantages.  It's been discussed before and it's not a new idea.

I've described every step in the process of making them so that anyone else can make them, too.

The disadvantages to this jig are several.  It's not stand-alone, but requires another jig such as the SVX-150.  It scratches the sides of knives.  It's easily damaged because the edge is so thin and so close to the grindstone.

The advantages are that it can be used for knives of all sizes, it can account for tapers on the sides of knife blades when setting the edge angle, and the offset of the blade in the knife handle is a non-issue.

I'm not here to sell them, I'm here to let people know that they can be built and used and are just one more way to modify a jig so that the Tormek machine is a more useful tool.
Title: Re: Homemade Knife Rest (HK-50)
Post by: Elden on April 15, 2013, 07:43:08 pm
The disadvantages to this jig are several.  It's not stand-alone, but requires another jig such as the SVX-150.  It scratches the sides of knives.  It's easily damaged because the edge is so thin and so close to the grindstone.
Thanks for pointing these out Herman. I found out about that last one the first time I used it.

For someone who may not have seen it, the jig can be built as a stand alone jig. See:

http://www.tormek.com/forum/index.php?topic=1605.0
Title: Re: Homemade Knife Rest (HK-50)
Post by: Herman Trivilino on April 21, 2013, 02:15:04 am
Used the HK-50 to sharpen some old hatchets today.  I don't own the axe jig so I can't make any comparisons, but the HK-50 did a mighty fine job.
Title: Re: Homemade Knife Rest (HK-50)
Post by: Herman Trivilino on April 21, 2013, 10:46:12 pm
I was expecting to use the HK-50 to sharpen my lawnmower blade today, but its shape won't allow it to rest flat on the platform.  I had to break out the SVM-45.  It'd been so long since I'd used it I had to get used to it again.  :)
Title: Re: Homemade Knife Rest (HK-50)
Post by: courierdog on January 01, 2014, 03:55:19 pm
Herman:
I have now discovered this portion of your thread which has the dimensions for the plate. Many thanks.
Some where I think I read that the platform was deforming at the thin edge.
I will most likely fabricate several plates before settling on one, Aluminum, Mild Steel & Stainless Steel
A very thin layer of Teflon on the plate will minimize any scuffing on a blade.
My immediate project is to sharpen my Japanese Kitchen Knives (Santoku & Usuba) which require a 10-15 degree angle for sharpening.
I have tried the Tormek Knife Jigs both SVM 45 and the SVM 14, 0 and I cannot make them work as intended.
I have jury rigged a version similar to the HK-50 and it seems to work better for me.
I would prefer a solution where the rest is horizontal to the top of the machine as I prefer not to work over a rotating wheel.
I would like to know how to post pictures directly & without using photo bucket.
I have another project on the go to sharpen my Metal Lathe Tool Bits.
Title: Re: Homemade Knife Rest (HK-50)
Post by: Herman Trivilino on January 02, 2014, 04:25:19 am
I will most likely fabricate several plates before settling on one, Aluminum, Mild Steel & Stainless Steel

I've made several out of wood, a couple out of some high density plastic that I found, and one out of aluminum.  They all work equally well, although the aluminum one is the most rigid out there on the thin edge.

Quote
A very thin layer of Teflon on the plate will minimize any scuffing on a blade.

How do you do that?  I'd like to give it a try.  I used some cheap adhesive-backed felt from a craft store and it works well.

Quote
My immediate project is to sharpen my Japanese Kitchen Knives (Santoku & Usuba) which require a 10-15 degree angle for sharpening.

Do you have the Japanese Waterstone (SJ-250)?  If not you'll need to use the fine side of the stone grader on the SG-250 for several minutes to make sure the surface is smooth as glass.

Quote
I would like to know how to post pictures directly & without using photo bucket.

You have to host the pictures somewhere on the web, there's no way to host them here on this site.
Title: Re: Homemade Knife Rest (HK-50)
Post by: courierdog on January 03, 2014, 05:15:21 pm
Herman:
Thanks for the valuable info.
I have the Tormek SJ-250 Waterstone as well as the SB-250 for my Metal Lathe Tool bits plus the original SG-250
I have been trying to think of a way to use a flycutter to match the curvature on a metal plate match the Tormek Wheel.
The large advantage with the Tormek is the knife edge will have a slight hollow grind edge to it as opposed the flat edge of the traditional Japanese waterstone. My normal 400 grit followed by 1000 grit followed by 5000 grit approach can be shortened to just the 4000 grit SJ-250 once the edge has been shaped using this new approach.
The point about the external picture hosting I do not like as many of the picture disappear when the user looses interest in the subject.
Title: Re: Homemade Knife Rest (HK-50)
Post by: Bernard Calip on January 04, 2014, 05:40:51 am
Herman,

This is my first post.

The white plastic material looks like Teflon to me.

I will be ordering my Tormek T7 on Monday.
Title: Re: Homemade Knife Rest (HK-50)
Post by: Herman Trivilino on June 13, 2014, 01:14:22 am
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.

Tool 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.
Title: Re: Homemade Knife Rest (HK-50)
Post by: Herman Trivilino on June 27, 2014, 04:52:41 pm
I've been thinking a lot about the design of the HK-50 and this passage in the Tormek Handbook:

Quote
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.

If you look at the ways in which the Tormek Tool Rest (SVD-110) is used,

http://tormek.com/international/en/grinding-jigs/svd-110-tool-rest/

there appears to be a conflict.  But the point is well taken.  Note that in every case where the SVD-110 is being used the edge angle, and thus the grinding angle, is very steep.  Close to 90o.  At this steep of an angle you really can apply most of the pressure to the tool rather than the tool rest.  But for shallow angles, like you'd use for a knife, most of the pressure must be applied to the tool rest rather than the tool.  If not, the tool lifts itself off the tool rest and the edge angle is no longer maintained.  This is a huge problem when grinding away from the edge, but manageable when grinding towards the edge. 

Thinking about all these things, and having received an Amazon gift certificate,  I decided I'd combine it with some bonus points and a bit of my own money and treat myself to a SVD-110.  It arrived yesterday and after fiddling with it and thinking about ways to attach a HK-50, I quickly realized that the base of the scissors jig that I've been using for this purpose is far better suited to the task.

Here's why.  Consider the distance from the surface of the tool rest to the center of the Universal Support, labeled d in this drawing.

(http://i1291.photobucket.com/albums/b553/htrivilino/ToolRest_zps4acafcb9.png) (http://s1291.photobucket.com/user/htrivilino/media/ToolRest_zps4acafcb9.png.html)

It's about 34 mm.

Now consider the same distance in the case of the base of the scissors jig:

(http://i1291.photobucket.com/albums/b553/htrivilino/Scissors_zps8b94f547.png) (http://s1291.photobucket.com/user/htrivilino/media/Scissors_zps8b94f547.png.html)

It's about 10 mm.

In other words, you can get the surface of the tool rest much closer to the Universal Support, and thus closer to the grindstone, in the case of the base of the scissors jig.  Therefore when attaching to the SVD-110 the HK-50 would have to be much longer, placing the grinding edge much further from the operator.  So my conclusion is that Tool Rest alone is ideal when grinding tools at blunt angles, but when grinding knives at shallow angles attaching the HK-50 to the base of the scissors jig is a better option than attaching it to the SVD-110.
Title: Re: Homemade Knife Rest (HK-50)
Post by: tooljunkie on December 19, 2014, 06:45:38 am
Herman
Do you have any pictures of your jig in use with some knives.?
Does your jig work better for small knifes?

Thanks
Tooljunkie Dan
(You can never have too many tools)
Title: Re: Homemade Knife Rest (HK-50)
Post by: Herman Trivilino on December 19, 2014, 07:41:37 am
Here's a video ...

https://www.youtube.com/watch?v=AcWAkQmoU8c&feature=youtu.be

The jig shown in that video was the first prototype, which is described this thread ...

http://www.tormek.com/forum/index.php?topic=1560.0

Since that time Tormek has come out with their Small Knife Holder, the SVM-00. I've not had the opportunity to try it yet.

The HK-50 works well for small knives.
Title: Re: Homemade Knife Rest (HK-50)
Post by: arnman on January 13, 2015, 08:00:10 pm
Herman,

I am a new Tormek owner, as of this past weekend.  I read through this thread and watched your video, which was very informative.  My head is full of new information I am trying to keep track of at this point!

You may have already answered this, but is there a reason why the SVD-110 could not serve as the home made knife rest?  Also, did you list the dimensions of your steel plate somewhere?

Thanks.

Steve
Title: Re: Homemade Knife Rest (HK-50)
Post by: Ken S on January 13, 2015, 09:56:37 pm
Steve,

If I may, I will add my two cents. I do believe the SVD-110 can be modified into a knife jig. However, you may go through several jigs before you get one to work well. I know; I cut mine roughly in half. Neither half works well. The platform of the scissors jig sits lower.

I have not completely given up on the project. I have all the Tormek knife jigs. The few very small knives which do not fit the small knife jig well can usuallu be sharpened on the Tormek freehand.

Herman has also sharpened a machete with his jig. If I ever need to sharpen machetes, I will follow Herman's lead and build one of his jigs.

I recommend you start with the regular Tormek knife jig and build some experience.

Ken
Title: Re: Homemade Knife Rest (HK-50)
Post by: Herman Trivilino on January 14, 2015, 03:00:20 am
You may have already answered this, but is there a reason why the SVD-110 could not serve as the home made knife rest?


Look at Reply #57 in this thread. The platform is too far from the US support rod.

Quote
Also, did you list the dimensions of your steel plate somewhere?

13 mm thick, 50 mm wide, and 120 mm long.
Title: Re: Homemade Knife Rest (HK-50)
Post by: arnman on January 14, 2015, 03:37:12 am
Ken and Herman,

Thanks for the explanations.  After studying the pictures a bit more and re-reading #57, I can understand the limitations of the SVD-110 for the HK-50.
Title: Re: Homemade Knife Rest (HK-50)
Post by: Ken S on April 17, 2015, 01:57:46 pm
Looking at Herman's jig again, I thing using the scissors jig as the foundation makes more sense than using the higher center of gravity Torlock platform.

Ken
Title: Re: Homemade Knife Rest (HK-50)
Post by: Ken S on April 19, 2015, 12:18:30 pm
I happened to stop at my new local Tormek dealer on Friday. Just outside the door was the half off display. I love a bargain as much as the next person, and spotted a half off scissors jig. Thinking of Herman's HK-50, I thought I had a "find". Twenty five dollars US for a scissors jig. This particular jig was made for a Tormek clone. Not my first choice, but I only needed an extra platform.

The jig lacked Tormek's patented Torlock. it didnot have a solid appearance, but I thought it might be good enough. I went in the store and tried the jig on the universal support of the demo Tormek. With some force it slid part way until it stopped by where the locking screw was located. The price was no bargain if it did not work. The packaging had been opened before, no doubt purchased and returned.

For only a few dollars more, I can order just the Tormek scissors jig platform. (I already have a scissors jig.) I will put the platform on the list for my next future parts order from sharptoolsusa. I do think Herman's lower center of gravity plan works better than mine. However, intil My parts list gets long enough to warrant the shipping cost, my version will auffice.

Always examine a "bargain" very carefully!

Ken
Title: Re: Homemade Knife Rest (HK-50)
Post by: Herman Trivilino on April 19, 2015, 04:42:19 pm
Ken, you don't need a dedicated scissors base for the HK-50. Just attach the HK-50 to your existing scissors base, then remove it when you want to sharpen scissors.

If I had a bargain scissors base dedicated for HK-50 use I would probably cut it down like you did with one of your Tool Rest jigs. There must be used platforms out there whose scissors clamp has been lost, and are therefore excellent candidates for modification as a tool rest such as the HK-50. I use mine to sharpen a lot more things than just knives.

Did the knock-off scissors jig have teflon surfaces?
Title: Re: Homemade Knife Rest (HK-50)
Post by: Ken S on April 19, 2015, 06:20:06 pm
Good points, Herman.

Yes, I know I could disassemble the HK jigs from the scissors platform. I guess I'm a little lazy; I like "plug and play".

I have been looking for an inexpensive scissors jig or platform. I have thought about cutting it to fit both an HK40 and 50. It is easy to do with a bandsaw and a 1/8" blade. Drilling and tapping for metric 6 thread is no big deal. (It wouldn't even have to be metric.)

The clone jig had the teflon surface like the Tormek. In fact, it isn't a bad looking jig; it just didn't look as solid as the Torlock.

I know the HK can be used for lots of purposes; it's a very versatile jig.

Ken
Title: Re: Homemade Knife Rest (HK-50)
Post by: Herman Trivilino on April 19, 2015, 08:32:41 pm
I have been looking for an inexpensive scissors jig or platform. I have thought about cutting it to fit both an HK40 and 50.

There may be a way to further modify the Tool Rest jig that you've trimmed so that the platform is closer to the universal support rod. Tormek could make this a permanent modification for that jig. It would improve its usefulness. I don't see a disadvantage to that modification.
Title: Re: Homemade Knife Rest (HK-50)
Post by: Ken S on April 19, 2015, 10:04:09 pm
Herman,
I believe the original function of the flat platform jig was to sharpen turning scrapers. Knives which were too small for the standard knife jig were traditionally sharpened free hand. Then, in response to a forum question about sharpening small knives, Ionut, you and I "jailbroke" a couple jigs to devise workable platforms for small knives. The Tormek engineers must have been working on their small knife tool at the same time.

I do not expect to see a factory modified platform jig. The scissors jig platform is a better starting point. I do not expect to see factory modified scissors platforms, either. One of the Tormek philosophies is using jig controlled sharpening for minimum steel removal. The HK platforms also remove minimal steel. However, they require more hand skill.

Personally, I like having the choice. I have devised a knife setting tool to simplify knife set up. This tool works best when used with Tormek's small knife tool. Other times I prefer the simpler HK.
Choice is good.

Ken