Hand stubble

[daved]

I had my first go at sharpening a knife last week. Well, you warned that testing your knife on your arm will leave you with odd looking bald patches. As a proud owner of a new patch of short spikey hairs on the back of my hand I can tell you that the regrowth looks far weirder than the baldness!

I recently bought a "traditional" Mora knife which was unfortunately only sharp enough for letter-opening and butter-spreading. Having progressed through sanding off the slippery orange paint and discovering all about danish oil, I thought it was time to get it sharp. I thought I would write up my experience because it might be useful to other beginners and I am hoping that some of the experts here might be able to help me improve my technique.

I decided I would give a waterstone a go as these seem to be pretty popular here and there is quite a lot of instruction available in how to use them. This made them seem like a good bet for a beginner. I started with the coarse side of a combination stone (1000/6000) after soaking it for about 10 minutes and set it up on the table.

I coloured in the bevel with a marker pen, as suggested in the tutorial and with a deep breath, pushed the blade across the stone. The pen trick is pretty useful way to show where you have sharpened and if you are doing it evenly. (Although this is a really great idea, it has its limitations, which I will come back to later).
The first thing that struck me was how little of the width of the blade I could cover at a time as it is 4 inches long and the stone is only 2.5 inches wide. I tried holding the blade diagonally across the stone and also tried sliding it across the stone from hilt to tip. Both of these approaches made it more difficult to keep the bevel flat on the stone and still didn't cover the tip of the blade. Checking the ink, things seemed to be going ok so I tried to work out how to sharpen the tip. I found this surprisingly difficult to do and had a frustrating time trying to scrape the ink away. I am not sure what the best tactic is for this area as I only seemed to keep a tiny strip of metal in contact with the stone at a time. I tried changing the orientation of the blade as I went around the curve of the blade so that the current portion of the blade was at right angles to the direction of motion. (Hard to describe, but if you pick up a knife I hope you will see what I mean). Although this seemed to work quite well with respect to removing the ink, it proved to be a big mistake (more later).

Having re-coloured and removed the bevel a few times, I decided it was time to work on the other side of the blade. I found it quite difficult to move the blade towards me, as is usually recommended, so instead I shifted it to my other hand and pushed it away as before. I found this much easier to maintain the angle. After doing that side, I switched to the finer grade and worked on both sides, for as long as my patience lasted.
The result - a slightly less blunt knife with a very patchy bevel geometry - aaargh .

What I found:
Standing at the end of the stone makes it difficult to maintain the angle over the whole stroke. Standing side-on to the stone and going left-right is much easier.
Controlling the angle is most difficult at the start and end of the stroke, particularly if you move too quickly
Pulling a blade towards you (cutting edge first) is quite difficult to control and I ended up producing a secondary bevel in places.
The tip of the blade is much harder to sharpen
Changing the angle of the stroke around the curve, as I did, leads to a curved bevel.
Polishing with a 6000 grit and then examining under a bright light makes it much easier to see what you have done to the bevel (sadly, in my case ).

What I would like to know:
How wet should the water stone be during use?
How best do you tackle the tip of a knife?
Should you be getting a burr before switching to the other side? Should you get one on the new side too?

Disheartened, I cleared up and had another go the next day, with not much more success.
What I found this time was that unless your bevel is already flat, the ink trick won't help you get a flat bevel unless you are checking and re-inking after each stroke (!!!!) otherwise, removing the ink evenly will just preserve the shape you have got. Reinstating a flat bevel that you have inadvertently convexed or added a secondary bevel to is difficult on a 1000 stone - just too slow and it just seems to get worse.
Having failed a second time, I took a close look at the blade and noticed that some of the original grind scratches were still visible midway up the bevel, I also noticed that there were small "islands" of ink at various points along the glade. Looking along the edge, I noticed that this looked a bit wavy too. Basically, the blade was rather warped and parts of it were not properly making contact with the stone. I think the slurry on the stone rather than the stone itself was removing the ink from these depressions.

Frankly, it seems to be an exercise in futility to try to sharpen a flat ground bevel, unless the blade is straight and the bevel is flat (OK, probably stating the obvious there). If I hadn't had a go and polished with a fine grade abrasive, I would not have found out about the problem, so it wasn't all a waste of effort producing a blunt semi-convex butter knife with a secondary bevel! (muttering under my breath).

Once I had realised what the problem was, I decided I needed a much coarser abrasive to sort it out and resorted to good old wet and dry paper (P180). This was not nearly as aggressive as I feared and, compared to the waterstone, was relatively pleasant to use. I found that you needed to pull the blade (trailing edge first) rather than push, otherwise the paper would wrinkle. This time I only moved the knife perpendicular to its length, even around the tip. The extra width of the paper made it much easier to smooth out the whole length of the blade and transition to the tip, especially as the blade tapers from about 3mm thick to 1mm around the tip. I had to sacrifice a LOT of metal but I have managed to re-establish a flat bevel and succeeded in raising a burr on the edge. Even the curved tip is relatively sharp.

Moved back to the waterstone to try to smooth out some of the scratches and then stropped on a belt. Result: bald hand! OK, it is not quite up to razor sharpness but I am still pretty pleased with the result.
My technique with the waterstone is still rubbish and I think the difficulty of using these can be underestimated. I learned an awful lot during the process, but would rather not go through it again!
Moral of the story: check your blade is straight before you begin!

Sorry for the mammoth post but hopefully hearing about my mistakes might help a fellow beginner.
Please pitch in with any hints or tips - I am eager to improve my technique.

 

[Doc]

It's much better to practice sharpening on a cheap knife. The downside is that a cheap Mora may need a bit more work to get the bevels really flat.

I have only ever used wet and dry paper (used wet!) for regular sharpening at home. In the field I have a 600 grit diamond stone.

Once the bevels are flat, I seldom need to go coarser than 600 grit. I then use 800, 1200 and finally 1500 wet and dry. Then use a Starki sharp to strop with (it is just leather and aluminium oxide paste). The bevel looks like a mirror.

 

[leon-1]

I have been sharpening with both oil and wetstones since I was in pre-teens.

The points that have been brought out are very valid and people that have been sharpening knives for long periods of time tend to forget that in the beggining it was no piece of cake and that there are areas which cause problems. So fair comment

 

[daved]

Leon,
yes, as a beginner I certainly found it harder than I expected. I am hoping to encourage people to persevere as I managed to get a reasonable result in the end, but only after getting thoroughly disheartened and coming close to giving up. Without the tips and hints here, I don't think I would have got anywhere.

Eager to improve - any hints gratefully received (especially about how to tackle the tip)

 

[gregorach]

It does take a bit of practice - I find that the single most important thing is to be able to maintain a consistent sharpening angle. Take your time!

I do almost all of my sharpening using a very fine Arkansas stone - it takes a bit longer and is no use for serious grinding, but assuming you've already got a decent edge it's just the business for keeping it sharp.

I tend to tackle the tip seperately from the rest of the blade. I just rotate the blade so the point is away from me and sharpen using the same technique - but pushing along the blade rather than across it. A bit like sharpening a chisel. Maintaining the proper angel here is more difficult again, so keep practicing.

The only other piece of advice I'd give is not to regard sharpening as a cut-and-dried process. I see lots of recommendations to do x passes on one side, followed by x passes on the other, then alternate passes for y times, etc... That's not how I sharpen. The thing is to examine the blade carefully at every step of the process, think about what you're trying to achieve, and take your time. With practice you'll develop a "feel" for it.

 

[leon-1]

Stuart used this method on an extremely blunt woodlore in Namibia and I was surprised at how effective it is, it should be good for working towards the tip.

Take a pocket stone, lay it flat on the surface of the blade you wish to work on, then push the stone along the blade (if you have seen "Highlander" there is a part where he is sharpening a Katana and he draws the whetstone along the blade that is the sort of motion that you are after).

If you work on the last third of the blade (working from ricasso/gaurd to tip) this should do the trick for you, it will take a little time, but it will get there.

The main thing to learn about sharpening is there is always another method and although it may not be your normal method it doesn't mean that it won't work. This was not one of my normal methods, but it does work.

Normally I draw a knife across a stone in a diagonal motion, my body oblique to the side of the stone, I will draw maybe ten strokes on a side before swapping to the other side when using a coarse stone.

when I am using 2500 grit wet n dry (I have mouse matt variations and solid depending on whether I am working on a convexed edge or not) I will be using a single stroke per side. This goes the same for the 6000 grit and the strop.

Currently I use a mix and match process. I start on a 250 grit wetstone (for grinding), then move up through 400, 600, 800 grit wet 'n'dry (this helps to remove the larger scratches and makes it easier getting a nice finish). I then work on a 1000 grit wetstone, 1500, 2000 and 2500 grit wet 'n' dry (these are good for maintaining an edge and leave a reasonably polished finish). I finish on a 6000 grit stone, a peice of paper, then strop with compound and then strop without compound.

Normally there is no reason to go above 2500 grit wet 'n' dry and a strop.

If I need to remove a lot of metal I will sometimes use a figure 8 motion on the stone, not everyone gets on with it, and that seems a fair bit quicker (probably because of the continous motion).

I am also a fan of the Lansky systems (I don't have one, although I have used them), for helping to reprofile an edge they are very good.

In the feild I like ceramics, but at the same time I like the DC4 because the diamond stone on it is far coarser than the medium stone on my ceramic combination stone. So I have now dug out my old diamond stone (it was supposed to be fine, but I always found it rather aggresive), between the three of them and my belt you can keep most any knife sharp in the feild.

One thing to bear in mind is that most pocket stones can be replaced with a peice of wet 'n' dry glued/stuck to a peice of board and they won't cost the earth to replace if you lose or damage it in any way