PM2 on an Edge Pro

[Menace]

I posted this on several forums so some of you may see it several times but bear with me as I'm trying to learn and gather as much info and advice as possible.

Maybe some of you guys who are more experienced with the edge pro apex can help me out, how do you sharpen knives with a big up swept belly?

For example I'm trying to sharpen my Paramilitary 2, and the following three pictures will show you how I'm holding it on the edge pro's table and I rotate the knife as I follow through with the stroke in order to get all of the blade

starting position




finishing position

Now you can see from this picture, from the sharpie on the edge, that the stone is only getting the entire edge in one spot, it goes from not hitting the edge at all to hitting the entire edge to hitting just the back bevel.



What am I doing wrong? I've got the angle set at 18 degrees (whatever the green mark is)

Any tips would be appreciated, thanks

[chuck_roxas45]

Have you done some other knives on your EP? As of the moment, I still can't get my mind around your problem. What it looks like to me now is that the bevel near the tip is more obtuse than on the heel. Your angle setting just seems nearest to the actual bevel around the belly.

[Ankerson]

Why are you moving the blade?

For knives with blades around 5" and under you don't need to move the blade at all.

[suedeface]

Is that the factory edge you are trying to sharpen? If so,I would just create a new bevel to match whatever angle you want (18 deg), then the next time you sharpen it, it will be easier since you already have the edge angle established. My D4 ffg was like this when I first had to sharpen it after the factory edge was dulled. I use a Gatco and sharpmaker combo,and it took a full re-bevel to get a consistent edge, but now that I've got a fresh re-bevel (I use 20deg per side) sharpening only takes a few minutes.

[.357 mag]

I agree to rebevel it to what you want. Then you know what to do for next time. I sharpen all my knives at 15 degrees. Makes it easy and you don't have to remember down the road.:-)

[jackknifeh]

Is that the factory edge you are trying to sharpen? If so,I would just create a new bevel to match whatever angle you want (18 deg), then the next time you sharpen it, it will be easier since you already have the edge angle established. My D4 ffg was like this when I first had to sharpen it after the factory edge was dulled. I use a Gatco and sharpmaker combo,and it took a full re-bevel to get a consistent edge, but now that I've got a fresh re-bevel (I use 20deg per side) sharpening only takes a few minutes.

My bet is you are sharpening this knife for the first time. You will need to create a new bevel like suedeface said because the Edge Pro will create the entire edge at the same angle. The angles coming from Spyderco are not the same on both sides or the same along the same side. They are sharpened by hand on a grinder or belt I'm pretty sure. I get that from the video of them making a Native. EVERY Spyderco I've gotten looks just like yours when I start. It's not uncommon for this to be the case and the edge still be razor sharp. Spyderco's knives are normally sharp but the bevels are not consistantly the same angle. During the manufacturing process there just isn't enough time to spend on each edge like we do when we own them. Time is what it takes to get an edge to the condition you are looking for. Like Suedeface said again, once you have the even edge it's only a matter of seconds or very few minutes to keep it that way.

Set the angle to what you want then start sharpening. You will need to pay attention to the areas that the marker is not being removed. It it is removed from the edge but not the top of the bevel that means the angle there is lower than what the EP is set to. If it is removing marker from the top of the bevel then the angle is higher than the EP setting. You need to remove steel from wherever you need to to get the bevel flat from heel to tip. You may want to do this over several sharpenings. As long as the knife is cutting like you want it to that's the main thing.

If you really want to get accurat using the EP I'll get you to a thread I started several months ago about some "Edge Guide Blocks" I create for my knives. They are simple to make and hold the blade perfectly still as you stroke the edge. You may have noticed it's a little difficult to keep the blade from pivoting on the spine as you stroke the stone from heel to tip. The pressure of the stone against the blade wants to push the tip toward the EP. You therefore need to try to keep the blade from moving. Doing this EXACTLY the same on every stroke is difficult. My blocks eliminate this issue. They are only good for blades that are about 4" long and shorter. Knives you need to slide along the blade table of the EP (kitchen knives for example) don't need the blocks.

There are lots of people here that will give you good advice. When it comes to the EP I doubt if anyone knows more than me. I'm not bragging, I've just mastered the tool. If you talk to Ben Dale (EP inventor) I'm sure he'll disagree. I'm sure there is more I can learn also.

Jack

[Donut]

Check out this thread from Jack:

http://www.spyderco.com/forums/showthread.php?t=46425

[jzmtl]

It's quite common for a factory edge to be more obtuse toward the tip, you just have to reprofile the whole thing first time around.

[Evil D]

Check out this thread from Jack:

http://www.spyderco.com/forums/showthread.php?t=46425

That's pretty slick. Nice work Jack.

[Ankerson]

One you set the edge it will be nice and even.

[Menace]

thanks for the tips guys, I was under the impression that if you matched the Ep stone to the factory angle of the edge, then the EP would hit the entire edge along the entire length.

As for why I was rotating the blade, it's because if i didn't the Ep stone would hit the blade table. I quick back and forth with Ben Dale showed me that I was not putting enough of the blade up on the table of the EP.

I'll give it another go this afternoon and see what I can do with it. I love my EP and cut put a pretty nice edge on all my kitchen knives but I figured it's time to start practcing on my carry knives

[jackknifeh]

thanks for the tips guys, I was under the impression that if you matched the Ep stone to the factory angle of the edge, then the EP would hit the entire edge along the entire length.

As for why I was rotating the blade, it's because if i didn't the Ep stone would hit the blade table. I quick back and forth with Ben Dale showed me that I was not putting enough of the blade up on the table of the EP.

I'll give it another go this afternoon and see what I can do with it. I love my EP and cut put a pretty nice edge on all my kitchen knives but I figured it's time to start practcing on my carry knives

The EP is the only "high-end" sharpener I've used. There are others thay may work as well once you get a handle on the characteristics of the tool. Most tools are like that (the good ones anyway). You can set to match the EP to any angle on a knife your friend gives you to sharpen. That is of course if the angles on the edge are already consistant. If they aren't you will be able to make them so. If your friend has never seen a nice even edge on a knife he/she is bound to notice. Keep working with it and in no time you'll be getting results you've only seen in pictures. See Ankerson's picture above. I don't know what he sharpens with but his edges always look good. Too bad they aren't sharp. :) Sorry Ank, just kidding.

Jack

[Menace]

So, I gave it another go yesterday and I'm definetely getting closer.

Now, on the matter of reprofiling, how do I know whether or not my edge is centered? I was pretty aggressive with the 120 stone until there was no evidence of the factory grind left on either side which resulted in a pretty large burr being left on the edge that would flop from side to side as I reprofiled. How can I tell if I went too far on one side as opposed to the other?

[suedeface]

Take a marker and mark the edge again on both sides. Take a finer grit stone and lightly go over the edge with it. If you've gone far enough, a few passes with the finer stone should remove the marker from the entire edge.Then you know you've gone far enough. Be sure to check at the base of the edge (near the choil) and or tip as I sometimes seem to not take off enough material at these spots sometimes. Your edge bevel may still look uneven from side to side(as was the case on my D4 FFG) which is due to the angle the primary bevels are ground at the factory, but if you're scraping off the marker with the stones, your angle is consistent. Now for getting rid of that burr, well, maybe someone else can give you (and me) a bit of advice on that, because I still seem to struggle with the burr issue still. Hope this helps.

[jackknifeh]

So, I gave it another go yesterday and I'm definetely getting closer.

Now, on the matter of reprofiling, how do I know whether or not my edge is centered? I was pretty aggressive with the 120 stone until there was no evidence of the factory grind left on either side which resulted in a pretty large burr being left on the edge that would flop from side to side as I reprofiled. How can I tell if I went too far on one side as opposed to the other?

Once you have finished sharpening your knife, I mean you have gotten a burr one both sides and removed it and it is slicing paper real well look at both sides of the edge. They should be very very close to the same width. If one side is obviously wider than the other then the edge is not centered. You will need to remove enough steel from the side with the narrow edge until they are the same width.

Picture the knife blade as if you are looking at it down the edge from the handle to the tip. There is an imaginary line from the center of the spine up through the edge. The very edge should be on that line. If it is to the right of that line it needs to move to the left of course. Sharpen the right side enough to move the edge over. Think of shifting the entire edge (both sides) to the left until the sharp edge is on the line from the spine through the edge.

If you have questions, please ask.

Jack
PS edit: Be careful with the coarser stones. It's easy to remove more steel than needed before you know it. Keep checking your edge after every few strokes. Use the marker several times through the sharpening or re-profiling process.

[jackknifeh]

Take a marker and mark the edge again on both sides. Take a finer grit stone and lightly go over the edge with it. If you've gone far enough, a few passes with the finer stone should remove the marker from the entire edge.Then you know you've gone far enough. Be sure to check at the base of the edge (near the choil) and or tip as I sometimes seem to not take off enough material at these spots sometimes. Your edge bevel may still look uneven from side to side(as was the case on my D4 FFG) which is due to the angle the primary bevels are ground at the factory, but if you're scraping off the marker with the stones, your angle is consistent. Now for getting rid of that burr, well, maybe someone else can give you (and me) a bit of advice on that, because I still seem to struggle with the burr issue still. Hope this helps.

For the burr, VERY light strokes. When you feel a burr on one side lay the blade on the EP and very lightly slide the stone along the edge ONE TIME. I mean lay the stone on the edge and slide it toward the tip, don't do the normal stroking motion. Also use only as much pressure as the weight of the stone. Lay the stone on the edge at the heel and push the stone sideways with your finger tip to the edge. Sometimes with very small burrs you may even want to reduce the pressure by holding up slightly on the stone. Once you get to this point there are a couple of things to try. Take a piece of wood and slide the edge along the corner of the wood like you are trying to cut it. Use only the wieght of the blade. Two strokes at the most. If you need more than that the burr is still too big. That can remove small burrs. Or you can strop the edge. That's what I normally do. As you stroke the edge backwards if there is a burr on the edge you will see marks on the leather. You will feel the resistance also. When you don't feel resistance and it feels really smooth you are there. When stropping, use light pressure. It's amazing how much a piece of leather will do if it is treated with good stropping compound. I use DMT diamond paste but there are lots of others that I haven't tried but lots of other people love.

Jack

[5.56]

+1 Ankerson

It sounds like you need to spend more time with the 120grit and don't move the knife.

This is a crappy cell pic, after drinking, but you get the idea.

[Evil D]

I have a machinist ruler i use to measure my bevels to make sure they're about the same size on each side. It measures down to 1/64 of an inch. It isn't the best way to measure since some bevels can be really small, but it's a step above just eyeballing it.

[Menace]

Picture the knife blade as if you are looking at it down the edge from the handle to the tip. There is an imaginary line from the center of the spine up through the edge. The very edge should be on that line. If it is to the right of that line it needs to move to the left of course. Sharpen the right side enough to move the edge over. Think of shifting the entire edge (both sides) to the left until the sharp edge is on the line from the spine through the edge. helps.

I understand the concept, I was just wondering if there was a way to tell if the edge was off center other than eyeballing the bevels on both sides to see if they looked to be the same width.

[jackknifeh]

I understand the concept, I was just wondering if there was a way to tell if the edge was off center other than eyeballing the bevels on both sides to see if they looked to be the same width.

That's the only way to tell that I know of. I'd like to see a picture of the edge when you are done. :)

Jack