Jack Plane Camber - How much?

[city17]

Hi, I wanted to get a bit more efficient in getting rough stock flat and got a scrub plane which works great.

However now I'd like to add a camber to my jack plane as well so I can use that for rough work as an intermediary step (mostly for getting it approximately flat over the whole length, scrub plane is a bit too short for that) before using the jointer and/or smoothing plane.

Question is, how much of a camber should I put on it for this purpose? I've seen people put on a huge camber, which makes it basically a scrub plane. Wasn't sure what camber to go with when using it together with my dedicated scrub plane.

 

[Derek Cohen (Perth Oz)]

A scrub radius is 3". A scrubbing jack is 8". More general use is 10-12".



Regards from Perth

Derek

 

[city17]

A scrub radius is 3". A scrubbing jack is 8". More general use is 10-12".



Regards from Perth

Derek

Thanks Derek, how you’re working in the video seems to match my use case exactly. So the second plane you used has an 8” radius?

 

[Jacob]

Thanks Derek, how you’re working in the video seems to match my use case exactly. So the second plane you used has an 8” radius?

ECE scrub has a camber of 25mm radius and is very effective on what it's designed for; scrubbing off rough surface especially on reclaimed or painted old timber.
I've never checked the camber on other planes. They all vary somewhat. If it won't do for one job it'll do for another.
I guess Derek's 8 to 12" radius would be fine for lots of things.
All planes needs bit of camber IMHO and a dead straight edge gives no advantage and can be difficult to use.

 

[Trafalgar]

Hi, I wanted to get a bit more efficient in getting rough stock flat and got a scrub plane which works great.

However now I'd like to add a camber to my jack plane as well so I can use that for rough work as an intermediary step (mostly for getting it approximately flat over the whole length, scrub plane is a bit too short for that) before using the jointer and/or smoothing plane.

Question is, how much of a camber should I put on it for this purpose? I've seen people put on a huge camber, which makes it basically a scrub plane. Wasn't sure what camber to go with when using it together with my dedicated scrub plane.

For a No. 5: a sixteenth/strong sixteenth of an inch to the high point -- no nose, a smooth and regular curve is essential. Draw it in with a fine, felt-tipped marker (mark the high point dead center of the blade and a tick at the edges) and something round. A set of French curves will have something that matches. Connect the three dots. Hand grind it in on a coarse oilstone or sandpaper, then put a hollow in to just behind the edge by swinging it on a grinder. Hone as usual to finish.

You need one jack plane, one jointer plane, and one smoothing plane and perhaps a few irons of different shapes. A purpose-made scrub plane (the big Stanley) would be a sensible addition to these three. This is all you need in terms of bench planes to process stock by hand to a finished state. You don't need four or more of each.

 

[city17]

For a No. 5: a sixteenth/strong sixteenth of an inch to the high point -- no nose, a smooth and regular curve is essential. Draw it in with a fine, felt-tipped marker (mark the high point dead center of the blade and a tick at the edges) and something round. A set of French curves will have something that matches. Connect the three dots. Hand grind it in on a coarse oilstone or sandpaper, then put a hollow in to just behind the edge by swinging it on a grinder. Hone as usual to finish.

You need one jack plane, one jointer plane, and one smoothing plane and perhaps a few irons of different shapes. A purpose-made scrub plane (the big Stanley) would be a sensible addition to these three. This is all you need in terms of bench planes to process stock by hand to a finished state. You don't need four or more of each.

Thanks Trafalgar. That's pretty much my setup, except I also have the Veritas Scrub Plane as well for the initial step if I need to remove lots of material. I added a camber to my jack plane yesterday and it's quite amazing how much more efficient it is.

 

[Jacob]

For a No. 5: a sixteenth/strong sixteenth of an inch to the high point -- no nose, a smooth and regular curve is essential. Draw it in with a fine, felt-tipped marker (mark the high point dead center of the blade and a tick at the edges) and something round. A set of French curves will have something that matches. Connect the three dots. Hand grind it in on a coarse oilstone or sandpaper, then put a hollow in to just behind the edge by swinging it on a grinder. Hone as usual to finish.

You need one jack plane, one jointer plane, and one smoothing plane and perhaps a few irons of different shapes. A purpose-made scrub plane (the big Stanley) would be a sensible addition to these three. This is all you need in terms of bench planes to process stock by hand to a finished state. You don't need four or more of each.

Or you produce a camber just by biasing the pressure from one side to the other freehand on oil stones, in the old fashioned way. If you have a hollowed stone it does it automatically!
I don't really hold with all that careful working to a prescribed line, and I avoid the grindstone altogether.
Scrub planes have recently been brought into fashion but originally were just any old small plane with a steep camber - very useful for cleaning up (scrubbing) when reclaiming old timbers.
Works by having a very tight camber on a narrow blade, which cuts through the rough surface into the clean wood underneath and avoids much of the grit, which may be embedded and gets lifted off in the shavings. More shallow gouging than fine planing.
Brilliant for taking off paint, which can blunt a straight plane edge very quickly.
Mines the ECE with 33mm wide blade and camber radius about 25mm. It can be hard work and the light weight of a woody is an advantage Too coarse for normal woodwork, brilliant for reclaiming old timber.

 

[Trafalgar]

It's a one-time shaping. After this is accomplished, you're free to maintain it in whatever manner suits. If you'll re-read my post, I am advocating shaping by hand. The grinder only comes into play to produce a hollow grind after the shaping is done. Don't have to hollow grind if you don't want to.

 

[Trafalgar]

Thanks Trafalgar. That's pretty much my setup, except I also have the Veritas Scrub Plane as well for the initial step if I need to remove lots of material. I added a camber to my jack plane yesterday and it's quite amazing how much more efficient it is.

If you have a scrub you probably don't need a jack with as much curve as I've recommended. But you'll figure out what feels right.

 

[thetyreman]

no camber on any of my planes, I just round the edges slightly, sharpening freehand.

 

[Derek Cohen (Perth Oz)]

no camber on any of my planes, I just round the edges slightly, sharpening freehand.

Of course everyone is free to do as they please, but do try a jack plane with a 12" radiused blade for fast waste removal. I think that you will like this.

I have never got on with smoothers with flat blades and clipped corners. They still leave tracks if taking more than a very fine shaving.

Regards from Perth

Derek