Convex Double Bevel Sharpening

[AndyT]

Relax everybody! There is now no need to disagree about which sharpening method to use - sharpening is obsolete!

I have had a big clearout - all of all my old-fashioned planes have gone in a skip and been replaced with one of these

- when I need a new edge I just throw the old disposable blade away and slip in a new, razor sharp one. Honestly, throwing things away is much better, and I really do feel that I am helping the economy this way.

 

[Cheshirechappie]

Relax everybody! There is now no need to disagree about which sharpening method to use - sharpening is obsolete!

I have had a big clearout - all of all my old-fashioned planes have gone in a skip and been replaced with one of these

- when I need a new edge I just throw the old disposable blade away and slip in a new, razor sharp one. Honestly, throwing things away is much better, and I really do feel that I am helping the economy this way.

Yes - well - that's all very well, but does the disposable blade have a convex bevel, a concave bevel, a double bevel, a flat bevel, a reverse ogee with quirk bevel, or no bevel at all?

I think we should be told.

(Erm - where can I get some disposable chisels? )

 

[AndyT]

(Erm - where can I get some disposable chisels? )

Some people have said these are good to throw away...

 

[Cheshirechappie]

Super - thanks Andy!

Soon I'll be all set up to make disposable furniture...

 

[sdbranam]

Here's a follow up post with video showing slicing through copier paper to demonstrate sharpness: http://www.closegrain.com/2012/07/convex-bevel-sharpening-part-2.html.

 

[bugbear]

Here's a follow up post with video showing slicing through copier paper to demonstrate sharpness: http://www.closegrain.com/2012/07/convex-bevel-sharpening-part-2.html.

Probably quicker to just use a power buffer, like carvers do.

BugBear

 

[dunbarhamlin]

I'd use scissors or a guillotine for that

 

[sdbranam]

Duh! Despite the link name in my last reply, it's using the "convex double bevel" method. #-o

 

[mtr1]

Your plane blade sounds very dull, and doesn't look like its cutting that Pine end grain all well either. Allowing for you taking time to explain your method, I estimate that your method takes about two minutes, probably about the same time as someone with a honing guide. I don't see any advantage in speed over a honing guide with your method. I sharpen freehand and would think I take about 30 seconds and I'm back to work, I also use a honing guide on occasion and I think that takes about the same time once I've got it in the guide. You are doing it freehand at least, but feel you demonstrate how not too.

 

[sdbranam]

Hi Mark,

In 30 seconds and back to work, how many grits are you going through? Do you ever end up going back and doing more grits? How often do you do either of these? Are you chasing the bevels back and forth, honing the secondary bevel back several time before you have to reshape the primary bevel back up to the secondary bevel, or do you follow some other practice?

Any other points of interest in your freehand honing? I'm always curious about how different people choose to hold their blades, what motion they use on the stone, how many stones they use, how long on each, how they do periodic maintenance differently from major resharpening, to strop or not, etc. I see on your website and blog you're using pretty hard woods, so clearly you have a need for good effective edges.

If I only go back a couple grits for a quick stop maintenance break, I'm only spending about 30 seconds. Here I showed a full sequence, a complete resharpening.

 

[Scouse]

Relax everybody! There is now no need to disagree about which sharpening method to use - sharpening is obsolete!

I have had a big clearout - all of all my old-fashioned planes have gone in a skip and been replaced with one of these

- when I need a new edge I just throw the old disposable blade away and slip in a new, razor sharp one. Honestly, throwing things away is much better, and I really do feel that I am helping the economy this way.

Buy that man a pint! Finally, after all this time in a sharpening thread, a voice of reason!

You know it makes sense...

I know you all want to have a go, so form an orderly queue... :mrgreen:

 

[mtr1]

Hi Mark,

In 30 seconds and back to work, how many grits are you going through? Do you ever end up going back and doing more grits? How often do you do either of these? Are you chasing the bevels back and forth, honing the secondary bevel back several time before you have to reshape the primary bevel back up to the secondary bevel, or do you follow some other practice?

Any other points of interest in your freehand honing? I'm always curious about how different people choose to hold their blades, what motion they use on the stone, how many stones they use, how long on each, how they do periodic maintenance differently from major resharpening, to srop or not, etc. I see on your website and blog you're using pretty hard woods, so clearly you have a need for good effective edges.

If I only go back a couple grits for a quick stop maintenance break, I'm only spending about 30 seconds. Here I showed a full sequence, a complete resharpening.

I do the least amount of sharpening I can for the job at hand. I confess that when I was younger I would spend more time on the stones, but I'm not sure if it was an ego thing like "my chisels are sharper, therefore I must be a better cabinet maker than you" or some such rubbish.

For general work with my native hardwoods there is no need to spend time sharpening on lots of different grits, I use a fine DMT and hold the iron/chisel 90° to the length of the stone, give it a couple or three swipes then get shot of the wire edge. I guess this is the minimalist sharpening approach.
I also have spare irons so I can swap to a new one and carry on working, and not do any sharpening. If I have a piece of timber with difficult grain, I will spend more time sharpening, perhaps two or three swipes on a finer stone. I have no idea what grit they are, its a red DMT, and a piece of slate..I think its quite soft, well I know it is judging by the gouges down one side. I have got some bits of paper that are stuck to a board that I got free with a tool purchase once, they do give a very polished edge, but feel there is no need to go that far with the timbers I use. If I'm using an oilstone (and I only use one for planes) then I move the iron all over the stone, but still at 90°. I re-grind occasionally when there is a need too, but wouldn't do this by hand. My bevels are flat, or there are two points of contact when just re-ground.
I realise that you are going through the whole process of primary bevel then secondary so the process is longer especially explaining it at the same time, but still think you are spending more time sharpening when you could be working. This is all just my opinion and I am wrong often, but Give the 90° thing a go, I find it fast and effective and it works for me. Are my tools blunt, no, they are sharper than yours.

See, there's that ego thing again, seems to be the root of most sharpening discussions.

 

[Richard T]

Now, Andy and Ellis, don't make me do it ... it's the wrong time of year anyway.

We have to wait till late October, when pixies dance and witches play (and everything is just plain wrong) before we can start to talk about the RB10 ... don't make me make Vincent Price come over there ... (again).

 

[sdbranam]

See, there's that ego thing again, seems to be the root of most sharpening discussions.

Yeah, it always amazes me how everyone seems to take sharpening as a personal insult! Thanks for being able to discuss it rationally (with a little awareness of the ego lurking in the background!).

So am I interpreting your description right, by 90 degrees to the stone do you mean a T, where the stone or DMT is the cross of the T and the blade is the leg of the T? Then moving the blade sideways? That's how Mike Dunbar does it in his "Sensible sharpening" on sandpaper. Or something different? And how do you decide it's good enough?

I'd love to see it in action, would you be able to post a video of it somewhere? These days even raw phone camera video does a great job. Makes it a lot easier to communicate information.

 

[mtr1]

So am I interpreting your description right, by 90 degrees to the stone do you mean a T, where the stone or DMT is the cross of the T and the blade is the leg of the T? Then moving the blade sideways? That's how Mike Dunbar does it in his "Sensible sharpening" on sandpaper. Or something different? And how do you decide it's good enough?

You are correct in your interpretation, and I decide it's good enough when it can do the job I need it for, if not back to the stones.

I'd love to see it in action, would you be able to post a video of it somewhere? These days even raw phone camera video does a great job. Makes it a lot easier to communicate information.

Really! It's just as you describe, there isn't a secret. I hold the bevel flat on the stone, jam it up and down a few times and back to work. Probably took longer to type this than do it. If I'm in a real hurry I will pick up another plane or chisel, this is a throwback to my price work days.

 

[sdbranam]

Ok, I'll give it a try. I have a set of the DMT Duo-sharps, including the red. But there are as many ways to screw up as there are to sharpen, no matter how simple the method may be, so it's always good to see it! It's easy for me to overlook subtleties that are totally obvious to you.

 

[sdbranam]

Ok, the results of my highly scientific test (being a scientifical cove constantly on scientifical quest): using a pair of DMT Duo-Sharp plates (Black/Blue=Extra-Coarse/Coarse, and Red/Green=Fine/Extra-Fine), I initially reshaped the bevel on a couple of chisels on the Black using side-to-side motion along the length of the stone with the chisel oriented 90 degrees to it, forming flat 30 degree bevel; I also flattened the backs on it. This gave me initial flat surfaces consistent with the way I would be sharpening them, eliminating any remnants of the previous surface.

Having established the desired shape, on to the actual sharpening. I used the same motion to sharpen on the Blue, then the Green (since that's finer than the Red, might as well go the finer step). I did about 10 strokes up and down on each. I assume that while you have enough experience to be able to achieve your results with greater efficiency in just a few strokes, I need more while I learn it (and this further assumes that more is indeed better!). I flipped the chisel over and ran the back up and down the Green to remove the burr. This gave me an excellent edge, holding on the surface of my fingernail as I laid the chisel down on it.

Trying each chisel on the pine end grain test block, I got similar fine shavings as in my video, but the cut surface left behind was not as clean, leaving instead some crushed fibers. So I repeated another cycle of Blue and Green, since I may not have spent enough time the first go round. Again, similar shavings, but surface still not as good. So I must be missing something in the fine details of technique.

But then it occurred to me to add a little stropping. I did the same stropping I showed in the video. The result was much more satisfactory, that last little bit I needed. Now I was able to get the same surface left behind on the end grain. Both chisels also easily sliced paper when rested on its edge as I did in the second video.

So here with just two surfaces, the Blue and the Green, using a moderate number of strokes, followed by quick stropping, I was able to get good results. Considering this was my first time using this method, I would call that success. As I've found with every other method I've tried, I'm sure as I practice it more I will get better and more efficient with it, being able to get the same results with fewer and fewer strokes.

Did I get my chisels sharper than yours? Dunno. Did I get them sharper than my other chisels? Hard to say. Now we're at the point where the objective differences between them are getting hard to judge; certainly I would say they have substantially equivalent edges. So this method is indeed faster than what I showed in the video to achieve the same results.

It does make me feel better about my Duo-Sharps. My personal goal is to be able to get the same results quickly no matter what method I use. I'm not necessarily looking for "the best" as much as I'm looking for equivalent proficiency regardless of method.

I feel another video coming on!

 

[mtr1]

Well, thanks for giving it a try, as we already know there are hundreds of ways to sharpen and I find this way quick. Yes, I forgot to mention stropping, and I do usually strop. Incidentally Pine is one of the timbers where I would spend a little bit more time on my irons/chisels, but I'm not a slave to sharpening.

 

[Jacob]

Well, thanks for giving it a try, as we already know there are hundreds of ways to sharpen and I find this way quick. Yes, I forgot to mention stropping, and I do usually strop. Incidentally Pine is one of the timbers where I would spend a little bit more time on my irons/chisels, but I'm not a slave to sharpening.

100s of ways, but having gone round the houses I am still fairly close to my starting point i.e. double sided oil stone, strop, freehand.
I've effectively added one finer grade, stopped worrying about rounded bevels (I use them instead), spend more time stropping and stopped using a bench grinder.

 

[bugbear]

Well, thanks for giving it a try, as we already know there are hundreds of ways to sharpen and I find this way quick. Yes, I forgot to mention stropping, and I do usually strop. Incidentally Pine is one of the timbers where I would spend a little bit more time on my irons/chisels, but I'm not a slave to sharpening.

100s of ways, but having gone round the houses I am still fairly close to my starting point i.e. double sided oil stone, strop, freehand.
I've effectively added one finer grade, stopped worrying about rounded bevels (I use them instead), spend more time stropping and stopped using a bench grinder.

I thought you'd followed your guru and gone for nice diamond stones? In fact, you said so in this very thread.

BugBear