Planing into an elbow.

[Rustybin]

I am in the process of building a bench with a dog leg back leg. My plan for flattening the backs of the legs is to use a milling bit in a router but I am intrigued as to how one would do this with hand tools. I am sure it must be a common problem but I don't recall seeing it solved and Google is letting me down. Any thoughts?

 

[John15]

Spokeshave?

John

 

[MikeG.]

Spokeshave?

John

Yep.

I'm intrigued as to why a bench needs bends in its legs.

 

[Rustybin]

My bad. It's an angle rather than a bend. The back of the bench is inclined i.e. the leg is vertical to the seat base and then inclined back for the bench back. Though now I think about it smoothing it into a curve could be quite nice aesthetically.

 

[Racers]

You can do it with a spokeshave, bull nosed plane, scraper, chisel, rasp, file.
It gets harder to smooth the closer you get to the angle, you can sneak up to the junction with shorter nosed planed etc but the closer you get the more tricky, I haven't has much success with chisel planes they seem just to dig in.
Card scraper is my favourite tool as you can use it as a straight edge to check your progress.

Pete

 

[ED65]

Gah, I'd just finished typing out the three ways I think a curved leg would have been done historically.

For an inside angle, as much of the surface as possible planed with a normal plane, then a bullnose plane, then the last little bit done with a chisel. Or normal plane for most followed by a plane that would actually get you the full way into the corner, e.g. a chisel plane or the front of a duplex.

 

[Rustybin]

Thanks chaps. I suspected there was a proper thing(s) for the job but wondered if I had just had a failure to think of a way of using more basic tooling.

 

[custard]

I am intrigued as to how one would do this with hand tools.

Interesting question. I use hand tools to do something similar when I make "butterfly cleats" like this,

These are jointing surfaces, so to achieve a gap free result they need to be precise to the nth degree, however I'd adopt the same general approach, but with a bit less rigour, for the application you mentioned, where it only has to look right as opposed to actually be right.

There are two tools that haven't been mentioned that I find useful. Firstly, a saw. At the very least I'd put a relief cut as deep as I dare right into the very corner of the angle, alternatively I might do the entire job with a saw and then just leave clean up and final truing using other tools. It's actually no different, in terms of the precision required, to dovetailing.

The second tool is a shoulder plane, but used across the grain rather than along the grain. That way you can get right into the internal corner and produce a pleasingly crisp internal angle. To avoid spelching you work from the outside in towards the centre.

Apart from that it's all down to a good wide paring chisel with a perfectly flat back.

Pete made an excellent point about a chisel plane digging in. Even with a sharp iron and a fine cut I find the exact same tendency, there's also the fact that without any toe to the sole it's maddeningly difficult to actually begin the cut cleanly and accurately. I know plenty of professional cabinet makers who have pretty much abandoned chisel planes for these reasons.

It's a bit of a digression but I suspect this speaks to an essential truth about the fundamental mechanics of planing, in that the pressure exerted on the toe of the sole, by the iron trying to dive into the workpiece, is far greater than is generally realised.

I lubricate the sole of my bench planes with a squiggle of candle wax, what I see in practise is that the wax on the sole gets removed in front of the iron faster than it gets removed behind the iron. I've often wondered if this is due to this same "turning" force exerted by the iron trying to dive into the workpiece, and therefore pivoting the plane around an axis in line with the cutting edge of the iron?

It would also explain why it's relatively easy to plane, even with a really long jointer, by just holding the rear handle and so plane one handed. If you watch experienced craftsmen planing long boards they'll sometimes do this in order to plane the full length of the board without having to move their feet.

 

[Rustybin]

With butterfly joints I tend to cut them out using a saw and tidy up with a chisel wider than the butterfly is deep but they are rarely more than 3/4" deep. These bench legs are 3" wide so I thought something less testing of my chisel skills would be useful.

I must admit I have never been tempted toward owning a chisel plane. The physics just look all wrong. Like slamming the front brake on on a motorbike. There are just too many unbalanced forces to make for a good outcome.

 

[Racers]

I only use the back brake on my motor bike at the lights.
If you are using the front brake correctly the back wheel should just off the ground!

Kawasaki ZXR750j by Racers, on Flickr

Pete