Saturday, December 31, 2011

Sharpening Question

This post is more of a question than an actual blog entry, but this site is intended to be everything I am doing in the woodshop, so here it goes.
This evening I purchased a honing jig and my first 800/4000 grit combination Japanese water stone, from our local Rockler affiliate store. To this point I have been using freehand scary sharp for my sharpening system, with moderate success. I felt the honing jig may help correct some of the inconsistencies I’ve been experiencing with my results. The water stone is intended to expand my horizons, increase my final polish grit and admittedly because most everyone seems to feel they are the shizzal.
First off let me say that my current stable of chisels is full of sway back nags way past their primes and/or glue worthy steeds straight out of the chute. I have four (4) Stanley’s that my father purchased sometime back in the late 60’s or early 70’s. These chisels have been through quite a bit and are in need of serious restoration, but that is exactly what I am trying to do, if only for sentimental reasons. My newer chisels are Stanley Fat Max chisels straight off Lowe’s shelves. I have put these chisels through the scary sharp system a couple of times and have on occasion had them fairly sharp for a brief moment. As I am sure is the case with many of the lower quality chisels the darn things simply will not hold an edge for more than two (2) or three (3) mallet blows.
Anyway, on to the question…

Yesterday while beginning restoration of my father’s old 1” chisel I notice the cutting edge wasn’t square. In order to correct the issue I use a small file and squared the end of the chisel. As I expected, this process left a flat surface on the cutting edge of the chisel. As I began reshaping the edge freehand I got frustrated with my results, because the edge seemed to be skewing as I proceeded. While I’d wanted one for some time, this is where I got justification for the honing jig. There is no justification for the water stone, so I’ll probably pay double for that one when it’s discovered.

Let me say I think once I master the honing jig I am going to love it. It definitely makes holding the correct angle a breeze. I can clearly see the difference in consistency in the scratch pattern on the bevel. My problem and therefore my question, is that the bevel plane and backplane never seem to get closer to intersecting and the right corner of the bevel continues to maintain a visible flat. I know based on all the videos and positive discussions I have read online it is most likely not the honing jig and is more likely error on my part. Can anyone provide suggestions or scenarios that may correct or cause this issue? I am stumped.
I will not begin to use my water stone until I get this is figured out because I am afraid I may damage the stone if it’s a technique or knowledge issue. PLEASE! Any assistance, guess or enlightenment is greatly appreciated!!!

Until my next post,

Keep Your Mind on your Fingers and your Fingers on your Hands!!!

2 comments:

  1. I'm not sure I'm getting the whole of your question: it seems like it may be two parts: 1. why can't I get the edge square to the side, and 2. why can't I grind it to a sharp edge all the way across.

    My thoughts, for what they're worth: with the jig, if it is properly machined, will hold the blade square to the sharpening surface (whatever that may be) To get it square, start at a 'severe' grit to remove alot of material fast and re-form your bevel angle. (start at 80-100 grit if you want to go fast). By the geometry of the guide, it will square the edge while forming the bevel. With this method, be careful not to press the whole edge against the surface, lest you twist the blade/guide to the incorrect bevel skew. Instead, let the guide determine the shape. If it's skewed, the first strokes will be with only the pointed corner touching. Proceed gently until you've formed a flat on that corner you can press against without rocking the blade. Continue until you've ground a new bevel all the way back and square. If it's still not square, it could be the guide. I think Chris Schwarz wrote a blog not too long ago about 'tuning' a sharpening angle guide.

    As far as squaring, The way I learned it was to take a extra fine sharpie and lay a small square on the side of the blade, mark a square line right near the cutting edge on the backplane, then work the blade until either, it's parallel to the line all the way across, or just touches it all the way.

    I personally have given up using guides, they really slow me down. I start with the bench grinder with a blue 3x norton wheel, using the 80 to rough shape, and the 120 to do finer work like the final hollow grind. I find that if you get the bevel formed with the hollow grind, the top and tip of the grind, when pressed onto your flat (paper/stone) lets you 'rock' the cutting edge into the cutting surface. With only the two points of contact, holding an angle freehand becomes easy. Note: To hold an angle freehand, I find it much easier to side hone (move the blade side to side, parallel to the cutting edge) that way I can focus on pressing down on the two points of contact instead of focusing on not rocking forward or back.

    Hope this helps!
    Best,
    Nick

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  2. I have the same problem with the chisel edge not being square, but I think it is because of my cheap sharpening guide. It really doesn't effect the use of the chisel that much, so I ignore it. I keep meaning to follow Chris Schwartz's guide for tuning up a cheap honing guide, but forget every time I go down to my shop.

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