Sharpmaker + Boa = Frustration

ZENGHOST

ZENGHOST

Joined
Jan 21, 2002
Messages
3,834
Just got my Sharpmaker in the mail today and I've been trying to use it to sharpen my Kershaw Boa (plain edge), but it's just not working. Up until now I didn't have anything to sharpen the recurve with so I just kinda let it go. I've so far gone 200-300 strokes per side on the sharpmaker (40 degree) and it can't even cut paper yet. Am I going to have to break the piggy bank to buy those diamond rods, or am I doing something wrong? I know I'm an idiot when it comes to sharpening, but using the Sharpmaker is not exactly rocket science. I would appreciate any advice before I go back and go through a thousand more strokes on the damned thing (if I don't throw it out the window first). Don't get me wrong, I love my Boa, but I'm carrying around a speed safe butter knife right now. Thanks.
 
Did your Sharpmaker come with a video? If so, that pretty much explains it. You're not stroking the blade against the flat side of the stones, are you? That'll dull a recurve.

The CPM440V of the Boa can be hard to sharpen, especially if you've let it get really dull. However, using just the "pointy" edges of the sharpmaker rods, I've been able to keep my Boa sharp. Try using the brown rods first, alternating sides. Stop every 10 strokes or so and see if you can tell any improvement. Once it's fairly sharp, continue with the white stones. It should eventually get sharp.

However, if it's dull as a butterknife, maybe you'll have to lay out another $80.00 for the diamond rods. The ceramic ones won't really remove much metal.

Good Luck,
Doug
 
I've been using the corners of the stones. I bought the Sharpmaker specifically to sharpen my recurve blades since I only had flat water stones before. I did watch the vid, and I'm doing exactly what they tell me to do. I'm pretty sure that the 440v is the root of my problems but I wanted to know if there was anyone else out that has had similar problems.

I bought the ultra fine stones, but they won't do me any good if I can't get past the medium hones. Looks like I'll have to spring for the diamonds as well--I hope my tax refund gets here soon.
 
Originally posted by jefroman
bestknives.com has the diamond sleeves for around 50 dollars.
Click to expand...

I only see the rods for 80 bucks a pair on their site.

Looks like I shoulda bought my Sharpmaker from them, it's like 10 bucks cheaper over there.
 
The Sharpmaker is an excellent example of the V type sharpener, but you need to put this type of sharpener into perspective. It is excellent for maintaining an edge and not so excellent for grinding a new one. My suspicion is that you let your knife go to the point that it needs a new edge, not just maintenance on the old one. A pair of diamond rods will help because it will speed up the process compared to ceramic ones, but you really need to think about a different kind of product to regrind the edge. After that's done, then the Sharpmaker will keep it sharp.

An inexpensive option is the Lansky system. It is a little cumbersome and slow but it will get the job done. If you have serration you can get the Universal kit. Or you can just use the edges of the stones for the curved portion of your blade. You can use it to regrind the bevels and that should put you back in business. Take care.
 
Each sharpening device with preset angle may match your original edge beveling angle or may not. Before making next hundreds of strokes try to check what exactly you are doing. Mark sharpening bevel with dark marker and do some strokes. If it will be wiped off at all sharpening area width or near very edge - this means you are really sharpening your knife but some wrong way. Then we could think together what is going wrong...

But I can bet the reason is different. If your marker will be wiped off only at the back of sharpening area this means you are regrinding your edge bevel to more acute angle and didn’t touch very edge yet. If so you should arm yourself with patience, regrinding edge bevel with Sharpmaker medium rods is pretty laborious and time-consuming work. Especially dealing with super wear resistant CPM 440V...
Diamond rods could be solution here.

If I’m right – proceed on one side until you will get continuous burr at the opposite one. When repeat on the opposite side, again until you get burr.

Try to keep your edge always perpendicular to movement direction at the point it touches the stone. This is very important working with Sharpmaker on pronouncedly curved and recurved edges.

Then change rods to fine and repeat all.

Last stage – do alternating strokes with each side with less and less pressure to get rid of the burr. Clean your stones with abrasive kitchen cleaner before this last stage, clean rods will remove burr easier and cleaner than clogged ones.
 
Nothing is wrong with you! The problem is that Kershaw ground that edge to about 50 degrees. Reprofiling 440V to 40 degrees(or 30 like I did) with your 204 Sharpmaker medium stones is impossible! Get yourself some course diamond stones, for me that was the only way I was able to get to the edge of my Boa and believe me I spent more than 3 hours trying before getting a course stone!! Once you get an edge on there look out, that baby cuts everything including fingers, no other knife has cut me more!!
Good Luck!!!
 
Thanks for the advice guys. Anyone know what the angle on the DMT Diamond Vee sharpener is? Does it match the Sharpmaker? I'd much rather have the sharpmaker diamond rods, but the DMT vee is a lot cheaper, even if they are only 4.5 inch rods.
 
I agree with those that said the angle is too different so in essence your trying to reprofile not resharpen. That can be a long long process with a sharpmaker, even with steel like plain old 1095. 300 strokes is not even a start with something like 440V. I have worn out one set of sharpmaker gray stones reprofiling 5-6 blades with softer steel than that. And those had edge angles that were fairly close to that of the sharpmaker. After a while you can see where the edges of your stone, curve inward and are worn away. Then its time for a new sharpmaker(stones). Recurves are tough to sharpen using anything other than a sharpmaker on the corners of the stones. A lansky is not the greatest either on recurves, and even with their diamond stones its not that fast on hard steel. I have no great solutions other than buying the sharpmaker diamond stones, and keep at it.-:rolleyes:
 
Wow, sounds like you got the triple whammy. First, 440V is very wear resistant and difficult to sharpen, and in my experience it is very difficult to get 440V to take a scary-sharp edge. Second, recurved blades are more difficult to sharpen than non-recurved blades. And third, if that knife really did come with an edge that's 25-degrees per side as roguesoul suggested above, you've got a *ton* of metal to remove before the Sharpmaker gets to the edge. Frankly, I'd have to think about whether or not I wanted to buy a knife with these characteristics.

Anyway, the best thing to do is to use magic marker on the edge, as Sergiusz suggested. Do a little sharpening, and based on the wear pattern of the marker, you'll be able too gauge your progress.

Diamond stones will help a lot. Remember that with a recurved blade, you want the sharpening stone to be much smaller than the diameter of the recurve. That means that you don't want a stone much wider than the flats of the Sharpmaker. Also, remember that with diamond hones, if you press the knife hard on the stone, all you'll end up doing is stripping off the diamonds and ruining the hone. Use a light touch and let the diamonds do the work. I remind you of this because you're probably a bit frustrated, and anxious to get a good edge, and I don't want you to ruin your expensive diamond hone by getting impatient and pressing too hard.

Good luck! Once you get a recurved blade sharp, the performance really is incredible.

Joe
 
This is kond-of for Joe:

Does it make a difference if you match the curve of the edge so that it is "perpendicular" to the sharpenign stone? if you keep a recurved blade held in one grip and you don't move the blade up and down at all, but just pull against the sharpmaker stones, don't the curves of the edge hit the stone at weird angles?

Let me try to explain more. If you had a wharncliffe with a straight edge and nothing but, you could point that thing parallel to the floor and just pull against the rods. The andgle of the edge to the stone would always be the same, which is fien for a perfectly straight edge. Now add a curved tip to the knife. Don'y you have to move your wrist in a downward motion once you get to the tip so that the curved edge meets the stones at the same angle as the flat part of the edge? if so, with a recurve, you'd have to do a lot of wrist manipulation in order to keep the edge "level" agaisnt the stones.
 
My Boa is super-sharp now, thanks to Sharpmaker diamond rods. They've made my life a whole lot easier.

Well worth the $50.

Mike
 
I was -never- able to sharpen a knife before I got the sharpmaker and I also got the diamond rods.
I have an old kershaw DWO folder.. the poor thing lost a screw on one side but is still very solid.
I guess the remaining screw actually goes all the way through and screws on the other side.
Anyway, the blade is stamped 3000.
It must be really hard steel, cause when I bought the thing it had a hair popping edge and dlept that for over 5 years.
Eventually it got too dull to cut anything, though.
I tried sharpening it before I got the diamond rods, and probably spent an hour trying to raise a burr on teh darned thing with no luck.
Once I got the diamond rods, though, it only took 5 or 10 minutes to get a burr on each side.
Now it is shaving sharp, though still not nearly as sharp as it was when I bought it.
It was incredibly sharp out of the box though - only other knife I had that was that sharp was a cold steel trailmaster.
I have only been using the steeper (30 degree?) rods on the sharp maker.
I do notice that when I sharpen it a bit, it -feels- very sharp, but if I cut 10 or 12 strips off a sheet of paper and touch the edge again, it feels even sharper (?)
Does that make sense???
 
Originally posted by jerrinfla
I do notice that when I sharpen it a bit, it -feels- very sharp, but if I cut 10 or 12 strips off a sheet of paper and touch the edge again, it feels even sharper (?)
Does that make sense???
Click to expand...

You're probably forming a little bit of a "wire edge" which is what a little bit of rough, floppy metal hanging off the true edge is. When you cut the paper (which is slightly abrasive), you're removing this wire edge, and getting to where the "real" edge is.
 
Originally posted by Crayola
Does it make a difference if you match the curve of the edge so that it is "perpendicular" to the sharpenign stone? if you keep a recurved blade held in one grip and you don't move the blade up and down at all, but just pull against the sharpmaker stones, don't the curves of the edge hit the stone at weird angles?
Click to expand...

Yes, I agree. I keep the part of the edge that is touching the stone, perpendicular to the stone. So, as I pull through the stroke, I move the handle up and down, so that the edge is always perfectly parallel to the floor. It's a long weird motion but it's second nature to me now. I start at the part of the edge closest to the handle, with the handle slightly raised. But the time I hit the top of the recurve, the blade is parallel to the ground. Then the handle goes downward, and parallel again at the very bottom of the belly. Then up again as I hit the front part of the belly.

Or, more simply: keep the edge perpendicular to the stone.

Joe
 
I have allways used a Lansky to sharpen knives and have recently switched to Sharpmaker after seeing all the good post about it. It is quite a job to profile a blade with it but I have found a cheap way to fix this. I use double stick tape and sandpaper to stick 1/2 inch strips of sandpaper on the fine stones and now I can profile any blade in minutes. I have seen post on standing course stones against the Sharpmaker stones but this was always a pain. The sandpaper can be any grit you like and with the tape only cost a couple of bucks and works great.
 
Being the impatient sort, and not being able to get the diamond rods at 1:00am, I spent most of the night just sitting in front of the TV working on my Boa. And if my hairless arms are any indication, I was successful. I am never going to let that thing get dull again.

Despite its lack of coarse stones, I have to say that I couldn't be more pleased with the Sharpmaker. I have been a knife knut for ten plus years now and have never been able to get a shaving edge on my knives before this. Now I want to go and sharpen everything in the house.

I still really want to get the diamond rods, but it's difficult to pull the trigger on $80 stones. New Graham has (had) a great price but are out of stock, and bestknives seems to have fallen in line with the other stores at the $75-$80 mark. I doubt this will be the last time that I have to reprofile so Diamonds are definitely in my future.

Joe-thanks for that tip about not pressing too hard, I didn't realize that you could strip the diamonds off the rod.

I appreciate all of your support in my sharpening madness. My knives would all be a lot duller if I had never found the forums, and I would be a hell of a lot more frustrated as well. Thanks, guys.
 
Oh What does the sharpmaker video covers?
I'm interested because everyone have rave reviews on the sharpener
 
You must log in or register to reply here.
Back
Top