how to sharpen a curved handplane blade?

[Brian Sommers]

I have a jack plane set up as a gouging plane. It works very good and removes lots of material.

I want to hone it up some and not only does it have an aggressive camber, but the blade is formed into a slight "scoop"

My fear is I'll flatten that out, so then do I use files? Which seems incredibly tedious.

[Bill Houghton]

When you say the blade is formed into a slight scoop, do you mean it's shaped like a gouge? Never heard of that in a plane.

You can get slipstones that should work. Google "gouge slipstone." That on the inside curve, and a regular flat stone (reserved for the purpose, maybe) on the bevel, and you should be home free for honing. As to shaping, you may find it hard to file it; I'd consider very coarse stones/diamond stones, if you're not comfortable freehanding the curve on a suitable grinder.

[John Crawford]

Others will advise you better, but just to get started: I wonder if the back (non bevel side) of your plane iron has been worn or incorrectly flattened by the previous owner? Sometimes people will put the back of the iron on a belt sander or something, and end up creating a hollow in the blade. Typically the back of a jack plane's iron is flat, so that it will meet nicely with the chip breaker.

But, maybe you have an interesting variant? If so, show us some pictures!

[Jim Koepke]

I have a jack plane set up as a gouging plane. It works very good and removes lots of material.

I want to hone it up some and not only does it have an aggressive camber, but the blade is formed into a slight "scoop"

My fear is I'll flatten that out, so then do I use files? Which seems incredibly tedious.

Work the bevel on the stones you have. There are variations on working a cambered blade and someone may be able to describe it better than me. If you change the camber slightly, you will likely not notice.

Is the chip breaker modified to mate with the scooped back?

Most of my blades do not have an intentional camber unless the blade is from a molding plane. Sometimes these will be worked in a push/pull method with the blade being turned fully through the curve on both the push and the pull stroke. Other times these are worked side to side with the blade being rotated through the full curve on the pass in one direction, then the other.

As far as the back of the blade goes to remove the burr that can be done on a strop or with some sanding abrasive if you do not have a slip stone.

If you use oilstones one of these might be to your liking:

http://www.danswhetstone.com/arkansas_files.htm

An Oval Translucent is too expensive.

If you like water stones then this page might be worth a look:

http://www.leevalley.com/us/wood/page.aspx?p=43071&cat=1,43072

There are also diamond stones shaped for your needs. I am not familiar with the sources for these since they are not something I use in the shop.

jtk

[Andrew Pitonyak]

Based on the confusion, I might like to see a picture of the blade to understand if this is just a camber on the blade.

I think that Derek Cohen had a great post on this, but I am not finding it at the moment.

[Mike Holbrook]

Sounds like you have a hollow ground plane blade that is also cambered. The hollow grind is typically made on a grinding wheel that leaves the curve of the grinding wheel in the bevel of the blade. Hollow grinding is a technique used to make final sharpening/honing easier. The camber, as you have found, allows you to remove more wood via the side to side curve in the blade.

I hollow grind all my plane blades because it makes them very easy to hone by hand. Honing is a term usually used to refer to final/fine stages of sharpening vs grinding which typically refers to about anything that changes the entire bevel or makes a different bevel. The "hollow" leaves thin edges at the top and bottom of the bevel. Resting both of these edges on a honing (fine) stone ensures that the bevel is being maintained at the same angle it was ground at. The thin leading edge of the blade is easier to hone as the hollow never touches the stone.

[lowell holmes]

You might want to try a different iron (blade) in the plane.

[Brian Sommers]

Please keep in mind that it is very shallow Hollow. The way it was ground was on a wheel. It came from a local Amish man woodworker here in town. He ground the blade on a pedal operated wheel. It works great. So to sharpen it I guess I should get a set of those sharpening files? Sorry don't have a clue of what they are.

[lowell holmes]

https://encrypted-tbn2.gstatic.com/images?q=tbn:ANd9GcQhzBFyRnGAxEF33d5Zj6H65H33TBTdm AmzAhILZf-_wX-zGybU2A
Maybe something like this?

Google "round sharpening stones".

[Brian Sommers]

Oh nice that would work. Good for my turning tools as well

[brian zawatsky]

Don't worry about the hollow. It doesn't need to be honed, just the cutting edge. The whole purpose of the hollow grind - to reiterate what was stated above - is to make final honing easier by reducing the width of the steel that touches the honing surface. Just hone & polish the leading edge of the cutter and the back of the iron. Easy peasy.

[Brian Sommers]

I found a video by Mary May https://www.marymaycarving.com/carvingschool/
where she turns her gouge and she moves it from side to side. My plane though is barely "cupped" so I'm thinking maybe brian is correct. I'm fussing over to little.

[Jim Koepke]

So to sharpen it I guess I should get a set of those sharpening files? Sorry don't have a clue of what they are.

Brian, the links in my earlier post should take you to the rounded stones if that is what you want.

Mary May also demonstrated her side to side style on an episode of "The Woodwright's Shop."

jtk

[Mike Holbrook]

As Brian said and I tried to explain. A rounded/cone... stone is actually counter productive for hand honing a hollow ground blade. The advantage of the hollow is the two very small edges it makes at each side of the bevel, even a "slight" hollow. Resting the bevel on those two edges assures the person honing the blade that the blade is at exactly the right bevel angle. A few strokes on a fine stone and that narrow little leading edge, which has now been honed at the correct angle, gets sharp without having to abrade the entire bevel.

If you try to abrade the entire bevel with a rounded sharpening stone you are defeating the entire purpose of hollow grinding. The advantage of hollow grinding is not needing to remove that much steel.

[John Schtrumpf]

Here is one method of sharpening a cambered blade. Skip to around 14:05 (your blade is already ground) in the video on the page and he shows the basic motion. Depending how worn or not,your blade is. You may only have to do the fine stone and remove the burr on the back.

http://www.renaissancewoodworker.com/fore-plane-restoration/