shapening for idiots...

RescueRiley

RescueRiley

Joined
Mar 22, 2006
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I don't really want to post this on maintenance and tinkering as I want to hear from my fellow w&s guys... Just looking for advice on hand sharpening..I read a piecce lately that said just sharpen 1 side till you burr it up than sharpen the other till the burr is gone..Is that all there is?? Is a bur sort of like a roll to the edge??just looking for help as I can never get my non convex knives the way I want them... Thanks...
 
i disagree on the exact description that is often quoted "sharpen one side to a burr then do the other side"-when i do this i tend to sharpen the other side much less, making for an uneven edge.

i prefer to alternate sides, or do a few passes on each side and then switch. this way each side will be polished more equally and the edge will stay more centered.

you do have to work at the edge until you get a burr though, so you know you have an edge instead of a flat spot. when you have a burr along the whole length of the edge, take it to a finer stone and repeat, you will notice the burr getting smaller and smaller. after you final stone, depending on the grit, you may not have a visible burr. but there is still one there. i like to skip several grits to a strop to tear off the burr so that the edge is less prone to degradation.

or you can just do like i do and sharpen everything convex style...well, except my mora. i like the micro-bevel effect of convex sharpening, as well as the very wide range of grits for you to finish to.

this set of videos (and especially the first part with a flat grind w/bevel knife) is good.
 
Thanks I still don't really grasp the meaning of a burr..and if you are alternating sides how do you get a burr?? Thanks again
 
The biggest trick to hand sharpening is a consistant angle. Hold the same angle for all strokes and sharpen till a burr appears across one side of the edge. sometimes the burr can be seen sometimes it is small enough to only be felt. The burr is that hairy, toothy edge that is formed by the leading edge rolling away from the stone(or diamond). You want to reduce this burr as much as possible by basically removing equal amounts of steel from both sides of a knife edge till the angles meet forming the cutting edge. With stones you will always have some form of burr left. That is where the strop comes in. The strop basically polishes the edge removing the final burr. For strops most use leather with a polishing compound rubbed on it but a simple strop can be a piece of cardboard from say a legal pad placed on a solid surface for a backing. Just draw the edge backwards across the strop using the same angle as when you used the stone and in (usually) 5-10 strokes per side, you will remove the burr and have a scary sharp edge. Now how to hold that angle in the 1st place? That is the tricky part. Some use guides,some use small ramps, and some use feel/experiance. The best way I know of is to somehow clamp down your stone to a solid surface and use two hands to hold the knife. Work it very slowly till you can hold the angle. It is not easy at 1st but the more practice you get the easier it becomes. For me I use a Sharpmaker to apply my edges. It is easy as pie for me because the angles are preset so all I have to do is make sure the blade stays straight as I pull it through and the edges come out great :)
 
You only need to get a burr on one side, then the other when sharpening from butter knife dull.
You can feel the burr if you run the edge of your finger nail across the width of the blade, spine to (past) the edge. Your nail will hang up on the burr if it is there.

If the blade is reasonably sharp, use the alternating sides method and don't worry about the burr.

That's my take on it, YMMV :D
 
have you ever ground a piece of metal on a bench grinder or belt sander? if you have, you are probably familiar with the lip of metal hanging off of the metal that is freshly ground. if not, take a look at this photo:

http://thesamovar.files.wordpress.com/2006/11/burr.jpg

you can feel a burr by placing your finger on the flat of the blade and moving it slowly towards the edge and then off of the edge. if there is a small catch or hangup, that is the burr. i will try to take some photos...
 
I use a Smith's diamond sharpender that has two sides. Coarse and fine, what is a reasonable amount of passes on a S30V blade that has not been abused in order to get it back to being shaving sharp? Do I even have the right kind of sharpener?

I can get it pretty sharp, but it's nowhere near being as sharp as I'd like it to be.
 
myright, i don't have experience with that blade steel or that sharpener, so can't tell you the appropriate number of passes...

but i find that a reasonable sharp blade will become shaving sharp with a strop, try that. a $7 strop is made from a $1 leather belt from a consignment shop and a $6 tube of gray tripoli from the hardware store.

here are some pics to hopefully help you understand a burr. this one is exagerated for effect, so your burr probably won't be this big (this was ground hard on a dull 40 grit belt)
non-burr side:
DSCN6683.jpg


burr-side:
DSCN6682.jpg


see that bright lip hanging on the edge on the burr side? that is the burr. holding your knife like this, edge down, under a bright light can show you a burr well. you can also hold it edge up right under a bright light to show you if you have any flat spots (they will look shiney)...instead of looking for a burr. if you have any flat spots, you aren't getting a burr, and you aren't getting sharp.

here are three photos to show how to feel for the burr:
start at the spine of the knife:
DSCN6685.jpg


move forward:
DSCN6686.jpg


and off the edge:
DSCN6687.jpg


hope this helps!
 
I find the convex and scandi edges fairly easy to sharpen...flat and hollow grinds give me trouble...With convex I just strop on a the ole sandpaper mouse pad till it feels good and touch up on a strop...and scandi is pretty much just lay the bevel flat and grind away and finish on a strop....but with out the guide lines I feel lost...some great advice so far Siguy Thanks for the help....
 
i tried making up a video, but youtube doesn't want to behave for me.

so it sounds like you are having trouble holding the angle...my advice would be to sharpen the bevels on the flat and hollow ground knives just like a full convex ground blade...

but if you want to use a stone, its hard to describe anything like that in words...i guess i'll use a specific case study for the sake of omitting generalities...

lets take a Case folding knife with full hollow grinds and a flat edge bevel. grab a sharpie and color in the bevels. lay your blade flat on the stone and press with your finger into the blade. you will feel the blade line up and lay flat on the stone. from that point, look at the edge of the knife. there should be some space between the edge and the stone. slowly tilt the knife forward, so teh spine is going up and the edge is going down, until the edge makes contact with the stone and then drag the knife across the stone at that angle. pick up your knife and look at it. chances are, a fair amount of the marker on the bevel was swiped away and replaced with fresh scratches from the stone. that's good. if not, adjust the angle to try to wipe away all of the black. once you get almost all of the black in one swipe, then you know you are at the right angle. that's the angle you want to keep going at, until you hit a burr. once again, i suggest switching sides of the knife every few strokes to keep things even. i also suggest re-coloring the bevels and checking them after every couple of strokes to begin with, to make sure you are maintaining that angle. once you get the burr, you can repeat down to your desired finish.

pretty quickly you won't need the sharpie anymore since you will get used to the angle of that knife and will be able to duplicate it everytime you take it to the stone...

let me know if you need anything explained further...
 
Assuming a new (flat) stone, you can (barely)feel when the edge grind is sitting flat on the stone. If you put the tip of your finger between the stone and the spine of the knife to hold that angle, you'll be able to duplicate it because it 'feels' right.

I've never tried explaining this before either...it's really a physical thing. Practice lots, you'll figure it out, it's more a 'feel' than a 'learn' type of skill. I figured it out on thrift store steak knives myself.

Some great tips here, gotta love this board !
 
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