Ken onion work sharp-blade grinding attatchment problem

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Aug 13, 2016
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Hi guys. Before I start, if I don't reply to your comments or I start another Identical thread it's because I lost this thread. I haven't figured out how to make it email the comments to me as well. That happened before and people flipped out at me. So if you have anything to say about that, I humbly ask you not to. I just want to get along and get some help while helping others on this site.
So I just got the Ken onion work sharp blade grinding attatchment and I sharpened a few knives. They come out dull. They won't even cut paper. There's 3 things I can think of that I may have done wrong:
1. I had the blade too close to the top pulley.
2. I had it at medium-high/high speed. (maybe too fast?)
3. I was using quite a bit of pressure.
Other than that, I do the exact same thing as in the videos on YouTube.

Could any of those been the reason the knives come out dull?
FYI, I start at p120, get a a burr on both sides then move on to all the other grits. Is there anything else you can think of that I'm doing wrong?

Please help, guys!

Thanks,

Bo
 
LOL. Okay, that's what I was thinking. And I deburr before moving on to the next grit too. I can't sleep at night if I leave that burr on there.

Thanks for the help man!

Bo
 
Yeah the first thing definately don't need much pressure ... let the belt do the work ... and too much pressure you will start rounding the edge
 
Okay. So I tried again with just the weight of the blade and it's not much better at all. I dont know what the hell I'm doing wrong. I'm doing it identical to the videos on YouTube. Could the belts be defective? Does anyone have any ideas please.
 
Oh ok so I tried again and it's a bit better. Sometimes it rips the paper and sometimes it cuts it. Should I just keep practicing sharpening with light pressure and hope my hand steadiness gets better, or should I do something else?

Bo

P. S. Sorry for the angry reply with the word "hell" in it. I'm just super frustrated and I get frustrated easily.
 
Email WorkSharp and politely ask for Brian Curran to respond. He's a great guy and he's always helpful!
 
LOL. Okay, that's what I was thinking. And I deburr before moving on to the next grit too. I can't sleep at night if I leave that burr on there.
Bo
Hi,
What do you mean by deburr , how are you deburring?
How well does the P120 burred edge slice paper?
Are you counting strokes?
 
It's possible to raise a burr on a dull edge. The question is: are the bevels meeting up on a line? Are you getting the bevels perfect on the roughest belt first before moving on? Are you letting the belt do the work? And are you using the lightest of pressure only sufficient to allow the belt to do the work?

I use the felt tip marker method at the first belt to help highlight any flaws or errors. I get the bevel and the edge perfect on the first belt first before I move on. Things that I missed before and prevented me from getting the knife sharp: 1) The blade is thick or uneven near the choil and needs to be thinned out. 2) the straight edge of the knife isn't planed correctly along the bevel, 3) the curved part of the blade isn't planed correctly along the curve, and 4) the tip isn't properly shaped. I looked at the edge with a 20X lighted loupe.

Only when I get the blade perfect on the roughest belt do I move on. And the remaining belt only serve to take out the scratch marks of the previous belt and to refine the edge. I learned here that you need to keep getting the pressure lighter and lighter. Sometimes, I even decrease the angle a bit of the knife to the blade by a hair. In my mind, if my pressure gets a hair too much, the belt will hit the top end of the bevel instead of cutting into the edge and removing the sharpness.

I don't know how much pressure you've been using but that was my problem before. It wore the belts too fast and I replaced them with new belts.

If I'm doing repair work with chips and too thick choils, I start with 80 grit. If there's no repair to be done, I start with a 60 grit. The sharpest I sharpen is to a 1200 Grit, 3 micron belt. If it's my EDC knife, I do the extra step of going to the 12000 grit, ~1.5 micron belt. I debur at the end with a wine cork and call it good.


Good luck.
 
Okay, thanks guys. I will contact Brian Curran
Today and I will try less pressure and getting the edge as perfect as I can today (as much as I can see). I will write another reply when I'm done to Let you guys know how it worked.

Thanks again for the help,

Bo
 
Oh, Rey HRH, what do you mean meeting up on a line? I'm going to try to get the bevel perfect on the p120 if I can, it's hard for me to tell if it's perfect, what should I look for? I'm letting the belt do most of the work but today when I try, I'm going to use as little pressure as possible.
 
I get the best results (for me) by using the standard guilded system because I find it more difficult to hold a consistent edge angle with the BGA. However some blades don’t work with the standard system so that’s when I use the BGA.

It helps me to use the flat reference plate before each pass on the belt. It takes a lot longer between passes but I am more confident that I am still holding the knife at the same angle from pass to pass.
 
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Oh, Rey HRH, what do you mean meeting up on a line? I'm going to try to get the bevel perfect on the p120 if I can, it's hard for me to tell if it's perfect, what should I look for? I'm letting the belt do most of the work but today when I try, I'm going to use as little pressure as possible.

"Meeting up on a line" was just a phrase I used at the moment because it applies to whatever bevel profile geometry - V-edge, Convex edge, etc. With a V-edge for example, each side of the bevel is supposed to be a flat plane that meets at the blade edge to form a V. The very bottom of that V is the blade edge and when you look at it straight on should be a thin straight line. Anywhere along that line should just be a single point wide. That would be sharp. I achieve that on the first belt that I use. I use the roughest belt I have depending on how damaged the edge is to get me the fastest. Once I'm there, then the succeeding belts are just to better refine the edge and the scratch marks on the bevel. I don't use the succeeding belts to do any additional work of getting the bevels to meet up on a line.
 
You didn't answer the one question that probably matters most... how are you deburring and finishing the edge? (Matters a lot with a belt sander).

Depending on how you're "deburring between steps", you also might be negatively affecting the outcome.

I think how you're finishing the edge, (probably in addition to too much pressure initially), may be the reason for your current results.
 
I thought I sent this yesterday but looks like it didn't send :
Dave 45, thank you for the tips. I'm just practicing on the BGA for now. Once I get good I'm only going to use it on recurve blades, Karambits, Kukris and other tricky knives. The reason I'm doing this is I want to open up a knife sharpening service one day.

So I tried again and it's much sharper. But it's still not as sharp as it should be. I am kind of shaky but I think it's because I haven't eaten (I don't eat until dinner usually). Do you guys think being shaky is going to make the knife duller?
Please tell me what you think!
I emailed worksharp and asked for Brian, and am waiting for a reply.

Also, Rey HRH, at what grit can you cut paper? Because right now I'm at 12000 with a strop and Just being able to cut paper.

And cbwx34, I just run a light (and I mean light) pass on the opposite side to remove the burr. Should I be doing something different?


Thanks guys,

Bo
 
I just thought of something. I'm now doing just barely the weight of the knife. Could I be using too little pressure? Instead of using more pressure should I do more strokes?

Bo
 
I just thought of something. I'm now doing just barely the weight of the knife. Could I be using too little pressure? Instead of using more pressure should I do more strokes?

Bo
Hi,
Yes, more strokes is better than using more pressure,
but
how clean/loaded are your belts?
How many strokes are you using at each step of the process ?
How well does it slice paper right after you raise a burr?
What angle setting?
Are you using permanent marker to see if where you're grinding (shoulder/edge/apex)?
What kind of knife is it? what sharpening angle? how thick at shoulder? how wide bevels?
Basically can you be more detailed on what you're doing exactly cause its hard to see from over here?

How much is the weight of the knife? ~110 grams (or 1/4lb or 4oz)?
worksharptools-wskts-ko_ug_-_8-16.pdf
says: Use very light pressure on belt (3/16” deflection)

if 4oz gets you 3/16 deflection then that sounds like good advice,
as you're finishing on your final belts, go lighter, 4oz and under,
the least amount you can use and still maintain control that still scratches your knife
 
Bucketstove:
I'm using belts that have sharpened about 4-5 knives, 10-13 strokes per side, I haven't sliced paper with it after raising a burr, just after I remove it, why is that important? I've done knives at 18 degrees but the main knife I practice in I have it at 22 degrees,
I used permanent marker, noticed I was hitting the shoulder so I changed the angle and it gave me a burr (wouldn't before), I'm still trying to find the right angle, I have a spinal cord Injury so it's harder on my left side. It's a cheap hunting knife and I don't know how thick it is or how wide the bevel is. I don't know the weight but it's a bit lighter than a kabar usmc. I think my problem is the angle I have the knife at and how it deviates from the flat angle on the guide. What is 3/16 deflection? Basically I'm doing everything the same as in the videos. The only thing I can imagine is the angle I have the knife at. Is there anything else you wanted to know?

Thanks for the help,

Bo
 
I was waiting to see if WorkSharp solved your problem... ever hear back?

Anyway, here's my suggestion. To start, make it as simple as possible. Set the wheels on the BGA to the closer position. For pressure... just enough to slightly compress the belt... either centered between the two wheels, or I like to sharpen a little closer to the lower one. Doesn't matter... just stay consistent. Medium speed should work.

Not sure what belts you have, but since you've been sharpening on the knife... use around a 220g belt. Mark both sides of the knife with a Sharpie. Set your angle and work one side, until you've removed the Sharpie and raised a burr along the entire edge. (Make sure you have one). Flip and repeat on the other side. Use the horizontal reference guide table (can't think of what it's called) to insure the knife is parallel for every pass... to insure you're staying consistent. Concentrate on each pass... one wrong pass at too high angle can erase your previous work, and make future passes less effective.

Step 2... remove the burr. IMO, you can't really do this with an abrasive belt... so hopefully you have either a leather or linen belt with compound that they now use (either will work). Remark both sides with the Sharpie. Again use the guide table. Start on the side that has the burr, and make 2 passes. You can use slightly less pressure, (what you want to watch is that you keep the belt compression the same) but make sure you're reaching the edge, and not pushing harder than when sharpening. Flip and repeat... 2 passes. Make sure Sharpie was removed along the edge on both sides. Now flip again and make one alternating pass each side. After doing each side one time check the sharpness. If not sharp, do another alternating pass each side, and check again. Shouldn't take more than 1/2 dozen alternating passes to clean up the edge and cleanly slice paper. If not, reset the angle on the BGA a couple of degrees higher and make a couple of alternating passes slightly less pressure... and see if there is a difference. Always use the reference table (we're in learning mode here). Be as consistent as possible with pressure, passes, etc.

Once this works, then you can reintroduce finer grit belts one at a time (if you want), and further refine the edge. (You may find you don't need to).

That's what I would do at this point... and see if a sharp edge can be obtained. When learning, the more steps you add... the easier it is to "kill" the edge... (regardless of what you're sharpening with).
 
I've been using the Ken Onion Workshop Model, I thought you had to have some exotic diamond sharpening system that cost $600 to brag about honing a knife here:rolleyes:. I've had good luck with mine so far, I'm not going for a mirror polish (although I totally dig that) just a usable working edge on my EDC's and kitchen knives. It does take some break in period (me mostly), I started with some junkers I had out in the shed and moved up to what I EDC. The DMT and Worksmith diamond hones are sitting in the drawer now, I'm sure they will still have a place to be used.
 
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