Sharpening scrub plane irons

[Jules Dominguez]

Are there jigs or tools for grinding and honing the radiused edge of a scrub plane, or is this something that's done freehand?

[Alan Tolchinsky]

Jules, I just tried doing this and I just did it on a grinder with the rest angled at 25 degrees. Then I honed it by hand on a water stone. I've read where the honing may not be necessary since it's only a scrub plane.

Sorry for wrong name Jules.

[Derek Cohen]

Jules

There are two ways to grind a curve onto a blade. The first is just do it freehand at a grinder. Since the surface is going to be chewed up (although it can be chewed up neatly!), the blade shape is less critical. So just get as close a curve as you can. The grind angle is best at 30 degrees.

The second method is the one I prefer since it produces a clean, smooth curve that looks good and gouges cleanly. Cut a piece of hardwood the same size as the blade. At the end of this piece, shape the curve you want to grind. Now, if you are using a Stanley blade, which has a groove down the centre, bolt the two together. If the blade you are using is solid (like the original Stanley scrub plane blade, or the LN or LV blades), then clamp it to the hardwood. What you are going to do is use the curve on the hardwood as a template for the blade. The curve runs up against the edge of the grinder rest, and the blade (bolted to the top) is extended until it contacts the grinder wheel (or belt sander) at approximately 30 degrees (preferred angle). You then turn the blade against the wheel using the curve of the hardwood template as a guide.

Once you have ground the curve (either fashion), it is necessary to hone the blade (sandpaper, waterstones, etc). It is not necessary to hone as high a grit as other plane blades as you are not trying for a smooth finish. A 1200 waterstone is adequate, although I would prefer to go to 6000/8000 myself and typically I finish with Veritas green rouge (0.5 micron).

See the picture below of the template and blade being ground on my belt sander jig. Incidentally, I have used this set up to take a blade from rectangular bevel to radiused bevel in about 5 minutes. I begin with 80 grit, move through 120, 240, 600 and 1300 grit belts then Veritas green rouge. This will shave end grain pine into wispy curls.

Regards from Perth

Derek

[Tom Saurer]

www.antuquetools.com/sharp/index.html

Freehand is fairly easy. Follow this tutorial, except do a figure 8 on the stone, rocking it slightly, from side to side.

[Tim Sproul]

Derek,

I like that idea.

[Jules Dominguez]

Thanks, guys. Derek, I like your jig and it sounds like your results are great. I'll give it a try.

Tom, that's a hell of a tutorial on sharpening. I bookmarked that site. I'd really like to be able to do things like that without mechanical assistance but I'm not sure I've got the manual skill. I'll also give it a try with an old plane iron, and hopefully I'll surprise myself. I think you guys that have the manual skills to freehand things may underestimate your own talent.

That's okay, Allan, I thought maybe you'd had a glass or two or three of wine with your dinner, which I sometimes do, especially when I'm eating steak or spaghetti. I appreciate your input, even though I'm not Ralph.

The old adage of "a lot of ways to skin a cat" could have been originated by a woodworker. The different approaches to a prolem by the folks on SMC really help me to keep things in perspective, and another adage - "different strokes for different folks" certainly holds true here.

[Alan Tolchinsky]

Thanks, guys. Derek, I like your jig and it sounds like your results are great. I'll give it a try.

Tom, that's a hell of a tutorial on sharpening. I bookmarked that site. I'd really like to be able to do things like that without mechanical assistance but I'm not sure I've got the manual skill. I'll also give it a try with an old plane iron, and hopefully I'll surprise myself. I think you guys that have the manual skills to freehand things may underestimate your own talent.

That's okay, Allan, I thought maybe you'd had a glass or two or three of wine with your dinner, which I sometimes do, especially when I'm eating steak or spaghetti. I appreciate your input, even though I'm not Ralph.

The old adage of "a lot of ways to skin a cat" could have been originated by a woodworker. The different approaches to a prolem by the folks on SMC really help me to keep things in perspective, and another adage - "different strokes for different folks" certainly holds true here.


O.K. Jules now we're even. My name only has one "l" not two. :) But I think my error was a little more egregous. And yes it was the wine I had; you are right there.

[Tom Saurer]

Practice...Practice...Practice. I used a jig for awhile and now I free hand. Start with a large chisel and then work your way down to smaller chisels and plane blades.