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[blgentry]

Hmm. Grepper you make the EOU devices sound very appealing. I looked at some videos and things. I don't know what kind of magic I was expecting. Like many things, there's no magic; just an (apparently) well executed device with a simple concept. It actually reminds me a lot of a device made by a bladeforums member named vasili. A Russian guy with some different ideas. His device used thread and a scale.

I'll need to read up on the EOU devices some more. I'm curious about their consumables cost and ease of use. Though based on a few videos, I guess they seem pretty darned easy to use.

Side note: In one corner of the computer world (Unix/Linux) there is a small powerful tool called grep. This tool is used to rapidly search through one or more text files searching for patterns and strings. "grep" is used quite frequently. It's pretty much indispensable. So, by that logic, a "Grepper" is one who searches for patterns (knowledge) and does it quite well.

Brian.

[blgentry]

Last night I gave in and ordered the Kalamazoo. It's shipping from California I believe. I live in Florida, so I think it will be mid next week before I see it. Now I need to go shop for belts!

Brian.

[blgentry]

I have ordered kind of a large assortment of belts, including a leather belt, medium scotchbright, and quite a few grits including 40, 120, and more.

I'm excited to try out these new tools. I've really enjoyed sharpening on the WSKO. I hope this will take it to a new level.

Lest Ken or Grepper think I'm not listening: I hear you both about light pressure. It makes sense from several standpoints: Low heat, low belt deflection (for a less convex edge), good control, etc. Finally, I personally believe that low pressure at high speeds translates to "finer apparent grit". A combination of the belt moving very quickly (compared to hand speed) and the light pressure on the cutting surface, should produce a scratch pattern that's several grades finer than what is printed on the belt. Am I crazy?

Thanks,

Breian.

[grepper]

Mr. Brian - Rarely do I flat out recommend, let alone highly recommend equipment, but the EOU testers are an exception.  As I said before, it is a must have for anyone at all serious about sharpening.  I use the PT50B to test every knife I sharpen.  Many times I’ll take 3 measurements along the blade just to check for a consistently sharp edge.  A few days ago I used it to test a 4” pizza cutting wheel I sharpened.  I depend on it and would feel lost without it.  It’s just that significant.
 
The “thread” that is severed when taking a measurement is called test media.  Is not just thread or mono filament fish line.  Test media took two years to develop.  Unlike thread or fish line, test media is moisture resistant, heat resistant, consistent in diameter and resistance to cleaving.  These properties provide highly accurate and repeatable measurements, something thread or fish line can’t come close to doing.  The EOU testers are accurate test instruments, not something cobbled together in a garage using thread or fish line. 
 
Assuming testing is done using the test fixture, test media cost is about $0.03 per test.  It is the only consumable cost.  New units include enough test media for 325-350 tests.  It takes 10 seconds or less to set up for a test.  Really quick and easy.
 
Congratulations!  You are the only person to have ever made the connection between Grepper and the Unix grep process, but you nailed it.  And besides, I think it makes a cool name.  I even named one of my cats Grep.  We called him Greppy or Grepper or just Grep.  My wife also had other terms of endearment for him such as golden boy (he was orange and white), but that’s another story.
 
I really hope you enjoy your Kally and will have fun experimenting with the variety of belts you purchased.  It seems like you mentioned a preference for a toothy edge like I too enjoy.  For that you will probably want to stay in the 150-200 grit range for belts.  That makes sharpening quick and simple.  Polished edges require more work with finer and finer grit abrasives and possibly compounds for polishing. 
 
I’ve experimented with sharpening down to 40 grit.  Coarser than 150 starts to be excessively aggressive and tears up the edge.  It’s a fun experiment nonetheless.  Get some old beater knife and have it.  Doing stuff like that teaches a lot about what grit does to steel.  Well worth doing.  The Kally is a handy general purpose grinder too.  No doubt you’ll find a use for your 40 grit belts like grinding the head off a bolt.
 
You’re spot on with your considerations of the benefits of light pressure grinding.  Additionally, heavy pressure makes deeper scratches in the bevel, hogs off metal quickly and produces big ugly gnarly burrs that can be more difficult to remove.  Using light pressure generates burr more slowly so it can be kept to a minimum.  I always prefer more light pressure strokes than fewer passes with high pressure.  It only takes a few seconds to pull the blade past the belt.
 
For me, the secret to getting sharp edges is to get a tiny, even burr then stop grinding.  Producing a bigger burr accomplishes nothing.  Once a burr is formed, grinding is done.  Burr removal is more difficult and is as or more important than grinding.  After a tiny burr is formed from each side of the blade and the burr is completely removed, almost magically the knife is very sharp.  It’s still a bit of a surprise to me every time I see it happen.
 
Keep us informed and feel free to ask questions!

[MaxtheKnife]

I have ordered kind of a large assortment of belts, including a leather belt, medium scotchbright, and quite a few grits including 40, 120, and more.

I'm excited to try out these new tools.  I've really enjoyed sharpening on the WSKO.  I hope this will take it to a new level.

Lest Ken or Grepper think I'm not listening:  I hear you both about light pressure.  It makes sense from several standpoints:  Low heat, low belt deflection (for a less convex edge), good control, etc.  Finally, I personally believe that low pressure at high speeds translates to "finer apparent grit".  A combination of the belt moving very quickly (compared to hand speed) and the light pressure on the cutting surface, should produce a scratch pattern that's several grades finer than what is printed on the belt.  Am I crazy?  

Thanks,

Breian.

you said medium scotchbrite.........purpleish in color/burgandy.........i think you want the blue fine one......medium is a different world......they offer a gray @ extra fine, but not needed as i have found it.....just fyi.

[blgentry]

Well, I may have just wasted $15 then.  If it doesn't work well, I guess I'll order the fine scotchbrite too.  Unless I can get them to change my order...


Thanks for the info.

Brian.

[MaxtheKnife]

Well, I may have just wasted $15 then.  If it doesn't work well, I guess I'll order the fine scotchbrite too.  Unless I can get them to change my order...


Thanks for the info.

Brian.

i sharpen a lot of mower blades..........after cleaning them, i pre-sharpen using angle grinder with 40 grit wheel or 80grit depending on condition...........in the past i would always finish on kally........grass is actually broken with power and not cut so i have been told by others, so my method is now just finish the edge with the medium scotchbrite belt and done after the 40 or 80 grit wheel on angle grinder.

you can tell what kinda yard someone has the the mower blade, so i ask them if they want it sharp also...........some do, but buying a new blade off the shelf, not sharp.

fyi

[grepper]

Yup.  You want the blue, very fine, SB belts.  See the chart below.  When the belt is new, breaking it in is necessary or they are to aggressive for deburring knife edges.  Please see the following post:

http://bessex.com/forum/showthread.php?t...47#pid5047

In the post you are taken to by following the link in the post above,  I was on the fence about SB for deburring, but that was years ago and I suspect I had not broken in the belt.  SB works great for deburring.  Use a very light touch with the SB when deburring.  It takes almost no pressure against the belt for the SB to do its deburring job.  Too much pressure can dull the edge.

The grey, super fine, may work too but I have not tried it.

You didn't waste $15 on the medium belt!  SB belts, generically called surface conditioning belts, are handy for a variety of tasks like rust removal and surface smoothing.  For me the coolest thing they do is to put a beautiful satin finish on metal.  Run some metal like an old piece of pipe against the open area of the belt and check out the beautiful satin finish it produces.  Then do it against the platen just for fun.  That satin finish not only looks cool but is fingerprint resistant.  SB belts are useful and fun.  I have all the colors.

   

A sharp mower blade cuts grass.  A dull one bashes the blades of grass in half.  Mow the lawn and then get down on hands and knees as though you were grazing.  Examine the ends of the blades of grass.  If the grass was cut with a sharp mower blade the ends of the blades of grass are cut neatly and smoothly as though snipped off with scissors. If the mower was dull then tops of the blades of grass are ugly, jagged, ripped, tortured, and bashed in half.  So, be kind to your poor grass plants and use a sharp blade.  After all, unlike dandelions they can't duck or get up and run away when they see the mower coming!

[blgentry]

Well, I guess I need to re-order and get a very fine Scotchbrite belt.

I enjoyed reading the linked thread. Sharpening stories are almost always interesting.

Brian.

[blgentry]

I've had my Kalamazoo set up and working for 2 whole days now. I've messed around and sharpened a terrible knife and an ok knife. Neither impressed me much. But that's ok. I'm just getting started with this machine.

I now see what all the talk about the platen is about! You essentially can't use the platen from the left side unless you track the belt *all* the way over there and make sure it's at the very edge. This is impractical and makes the machine make noises that sound like it doesn't like what you've forced it to do.

Looking at grepper's picture of his cool blade angle guide, it appears that there's no platen at all. Do you use a platen Mr. grepper?

I've read about cutting down the current platen; not sure that would work well for me. Maybe it would. I think I'd like to have a decent platen without a rolled over edge on either side so that I can approach it from either side and get all the way up to the blade without having the handle or guard of the knife run into the platen and block my progress.

I'd also like to have Grepper's guide! When is that thing going to be available sir? Sign me up.

Brian.