Instructables
Here is a picture of the finished sharpener ready to start sharpening small knives..
 
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Step 1: Knife holder plans

Picture of Knife holder plans
Here is the illustration  plan i drew  for making the knife blade holder.

Step 2: Pocket knive blade holder fabrication

Pic#1  Shows  me milling   the 3/8 wide slots by  3/4 of a inch long.

pic #1,2,3   show the end slots  for  the 2 bearings  that  will roll on the end guide to keep the blade straight as it is rolled across the grinding wheel.
 
Pic#5,6,7  Show the 3 center bearing slots for the leveling of the blade holder as it passes down the  the guide.

Pic#8  Shows the clamp attached  to the holder with 3  8 x 32 x 1/2 in  screws

Step 3: Main brackets and supports plan

Picture of Main brackets and supports plan

Step 4: Main bracket fabrication

Picture of Main bracket fabrication
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pic#1   Shows the (2) 1/2 inch diameter rods i drilled and tapped 1/4 x 20 x 1''  that will later be cut down to  1 1/2 inch long.

pic #2  & 3 show the drilling and cutting off of the (2)  height and support spacers

pic#4  Shows the (2) spacers installed and the support bracket welded between them.
 
pic #5 Shows the 14'' long  support rod for the slider bracket welded into place.

pic #6   shows the jack  support rod  for leveling the  14'' long support rod.

Step 5: Knife slider bracket plan

Picture of Knife slider bracket plan

Step 6: Slider bracket fabrication

Pic #1 &2  shows the milling of  all the surfaces  and the (2) slots so the bracket can slide towards the wheel for adjustments.


pic# 3 thru 7   Shows the slider bracket mounted in place ,  The adjustment bolt attached , The (2)  Spring assisted pins to hold tension on the slider bracket at all times, And the jack bolt attached and  leveled.

Step 7: Finding the right angle.

Picture of Finding the right angle.
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pic #1&2 Shows how i used a angle finder to get the  5 degrees i wanted for my pocket knife edge.

pic# 3&4  Shows the knife blade attached to the holder for both edges of the  blade to be sharpened..

Step 8: Video

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smalcolm2 years ago
Thats a neat idea, small problem.
This isn't suitable for knives, axes and lawn mower blades maybe, but not knives.
The grinder heats up the blades and weakens them, even when using oil.
The lansky system is a far better solution.
http://lansky.com/index.php/products/universal-system/
lime3D smalcolm2 years ago
Yes, I agree.
If, at 110 RPMs with a wheel that spends 1/3 of it's rotation under water, you are heating up the blade of a knife to over 420°F (the temperature you'd need to change the temper), I guarantee that you are using WAY TO MUCH force against the wheel. I sharpen knives, chisels, and other edges on a Tormek all the time and the blade barely gets hotter than room temperature.
As underground carpenter says if you are using a wet stone at 110 RPM you are in good shape. I too have a Tormek and this duplicates it in a primitive sort of way. However I don't usually use the Tormek to sharpen knives. It is better suited for more complicated sharpening like wood turning tools. For knives I actually like the paper wheel systems, they are really nice, produce a sharp edge and are quick. I mounted mine on a cheap grinder I bought at Big Lots for like $20 I also use a belt sander mounted perpendicular to the wall with a 15 micron belt. Sometimes it's really a matter of what mood I'm in what method I use to sharpen.
srilyk smalcolm2 years ago
Having used similar systems to the Lansky, I can tell you they're really not that great. They're awkward to hold and use, at least for me.

I find that my cheap $15 diamond stone set from Harbor Freight works just fine. At least until I can afford this: http://www.spyderco.com/catalog/details.php?product=82 ;)

The main advantage of using a grinder like this instructable is if you have knives with damaged blades that need some serious re-shaping - although the heat is a concern, I'm much more concerned about the amount of metal that's removed. The best sharpening uses a smooth straightening steel (http://www.cutleryandmore.com/victorinox-forschner-fibrox/smooth-polished-round-sharpening-steel-p16071). If that doesn't straighten the blade out, then you move to a fine stone, then finish with the straight steel. This removes the minimal amount of metal from your blade so (hopefully) it lasts several generations.

If it's a good blade anyway. If you have a cheep China stainless steel, by all means use this method ;)
coolbeansbaby68 (author)  smalcolm2 years ago
Actually it works just fine for knives. The wheel isnt moving fast enough and i am not taking alot of material off . And the water tank under the wheel keeps any heat away..
Bushie2 years ago

Pocket knives should NEVER go anywhere near a power grinder...

Those bench grinders are only suitable for the initial shaping of blades..

IF a pocket knife is worth owning, then it IS worth keeping it sharp correctly ~

And THAT means hand sharpening on a stone, with stropping on leather, and honing in between sharpening, with either a diamond hone or a strip of 'wet-and-dry' emery paper.
flamesami2 years ago
5 degrees?! that sounds like an inredibly fine edge. Do you put a secondary bevel on your knives, or does that edge profile work for you? I have no idea what you cut with those knives, but i would think that such a fine edge would roll before it actually blunted.
coolbeansbaby68 (author)  flamesami2 years ago
The edge works great. And holds it also. No secondary edge is needed . i think thats why 5 degrees works so good .
hmmm, what do you cut with those knives? I can't imagine them holding up to my using them (I'm a wood carver). Maybe my knives are just all c**p ;)
coolbeansbaby68 (author)  flamesami2 years ago
Its just a pocket knife. I could never sharpen one for beans . This works pretty good .The knife is a sog twitch . Very hard blade ..
TIGguy2 years ago
As a professionak welder of 20+ years and a knife collector for longer I can honestly say for normal knives this can work fine. As long as the metal does not turn color it hasnt gotten hot enough to ruin the temper of the blade. I have used bench grinders, hand grinders and belt sanders to repair friends chipped rough edges without hurting blade temper. Keep a container of water at hand and go slowly. If the blade starts to turn any color besides the normal steel color then it is getting too hot. I make one pass and cool the blade in the water. Cool it EVERY pass on the grinder. Make each pass one smooth steady motion also so as not to remove too much at a time.
coolbeansbaby68 (author)  TIGguy2 years ago
Can you see the little black tub under the wheel ? There is water in it . Also The wheel isnt turning very Fast .Its like 110 rpms for the big wheel and 3500 rpms for the small wheel on the other side . The big wheel is geared down very low . The only thing i need really is a finer grit wheel.....
Lol, I wasnt aguing. I was agreeing with you and clarifying for other readers. I think you have a good thing. For a finer wheel go to a welding supply store and ask about the fine ones we use for tungsten sharpening. I dont know the grit but they would be about right I think and after you could ise a polishing wheel for the razor sharpness!
coolbeansbaby68 (author)  TIGguy2 years ago
I didnt mean to sound snotty . People keep saying the same thing like your burning the blade i'm like no i'm not lol I was trying to get them to understand that the wheel isn't turning that fast to burn the blade lol
fespósito12 years ago
Very nice. Congrats.

I have a similar grinder, but the wet stone wobbles badly and I do not know the better way to fix it.

I will try to follow your idea (as a guide) but will implement it using aluminium instead of steel.

Thanks.
coolbeansbaby68 (author)  fespósito12 years ago
Thank you for the comment . If the wheel wobbles then the bushings are bad in the hub.
Thank you for the tip.
Maybe you need to trim the stone first.
You need to do this from time to time anyway, in order to keep it in good grinding condition. If you don't do this, the grinding causes too much friction and the steel can loose its hardness.
Thanks!
Ace Frahm2 years ago
Looks like if that blade ever catches on the wheel, it could fling right at you. How about a plexiglass shield?
Can you spare any details on the gearbox?
The grinder came like it is . Its a cheap harbor freight model . Look up bench grinders and you will see the one with the grinder stone on the side if it ..
pfred22 years ago
It is safe to assume you've never seen this?

http://www.tormek.com/en/jigs/svm140/index.php

I still want to clone the Tormek design for one of my grinders. I've done this for chisels and the like:

http://img37.imageshack.us/img37/1992/pict0241.jpg

I just got done sharpening a hatchet on the left side rest, worked great!
I suggest entering this into Noahw's Guide

http://www.instructables.com/id/Workshop-Challenge-Plan-It/
Great 'ible!
Phil B2 years ago
Very nice. I envy you for all of the machine tools you have available to you. Do you sharpen the point end of the blade by hand with an oilstone?
coolbeansbaby68 (author)  Phil B2 years ago
I use a oil stone for the tip.