Jamster21":35t51dzr said:
I use the same stones (600 - 1000 - 1200 usually, sometimes without the 1000) - what do I need to use after this to make a hand plane truely sharp?
Without knowing what woods you work or what you make I can't really answer. For many situations a plane iron can be adequately sharp straight off a 1200 grit stone.
What I can say is that in all the arguments about sharpening there are some fundamentals that seem to get consistently overlooked. If you trained in a professional workshop they wouldn't spent much time fretting about bevel angles or this stone versus another, instead they'd just hammer home some simple rules.
Step one, raise a burr. And raise a burr across the
full width of the tool. Check with your finger, from one side to another. If there's no burr then keep rubbing. If your fingers are tired or you're getting bored then tough, you
must achieve a full width burr. It makes sense to raise that burr as expeditiously as possible without being completely daft about it, so personally I use a 600 grit stone, but something in the range 600 to 1000 is fine.
Now that edge probably won't be fine enough, at least on a bench plane, so it's on to step two.
With a fractionally higher bevel angle you can quickly go straight from this to a polished edge. What's important about the polished edge isn't that it's polished, it's that the polish
shows you that you've done the job properly right across the cutting edge. A 3,000 grit stone would probably be perfectly adequate in sharpness terms. But a 3,000 grit stone won't raise a polish, so you'd never be completely sure you hadn't missed a bit. A 6,000 or 8,000 grit abrasive will raise a polish, and when you can see that polish all the way across you know the job's nearly done. But once that polish appears then immediately stop rubbing, the tool won't get any sharper once there's a hair's width polished edge, but you will make more work for yourself when you next come to sharpen by keeping on polishing. The wider that band of polished surface the more effort it'll be next time to raise a burr.
Step three, back off the iron to knock of the wire edge.
Step four, if you've got access to a power grinder make life easy on yourself by regularly grinding back at 25 degrees to within a mill of the cutting edge. As long as you stay a mill away from the edge then there's no risk of bluing the tool, and you'll preserve the camber that you've worked hard to perfect. Personally as soon as it takes more than ten strokes to raise a burr I head to the grinder.
So, how to get a polish?
You could use a 6,000 or 8,000 grit water stone. Personally I find them a bit of a faff with all the soaking and flattening, but lots of people like them.
You could use a very fine oil stone. Personally I find they're a bit slow to cut, but again lots of people like them.
You could use a strop. Personally I find strop's are a bit too much like hard work as it takes quite a few strokes to raise a polish, and I'd probably have to work finer than 600 grit before transferring to the strop, but lots of people swear by them and that's fine.
You could use a fine abrasive paper on a glass plate. That's basically what I use, self adhesive scary sharp paper on a granite block. Some people have issues with the paper tearing, but I don't seem to suffer from that problem.
And really that's all there is to it. Raise a burr. Raise a polish. Remove the wire edge. Get back to work.
It's simple, but I'm regularly surprised when I see hobbyists sharpen at how many **** it up, in particular by failing to raise a burr.
ccasion5:
