How to cut this curve

[Matt Sauber]

So, I am going to need to cut this curve in my current project. I'm thinking rough it out with a compass saw and then clean up with a spokeshave. Does that sound reasonable? How would you do it? Would I need a round sole spokeshave to cut this radius or what a flat bottom work here?
222860

[Jessica Pierce-LaRose]

I've got a horribly set panel saw that needs rehab that would be the perfect thing for that . . .

Depending on the curvature, you might be able to get away with a flat bottom shave, but I'd prefer a round bottom one. To fair the curve more easily, a compass plane or round bottom wooden plane might be even easier.

I've used a coping saw in places like this, but a turning saw would be even better. Compass saw could work fine depending on the tool.

Often with somewhat smaller arcs like this, I'll cut a series of straight cuts to get as close as I can - two big cuts starting as a V, and then a couple smaller Vs. Either instead of or in combination with this method, a few relief cuts if needed, followed by a bevel down chisel to split out the waste, and smooth it out with a spokeshave followed by scrapers.

Regardless of your method, remember to pay attention to the grain direction!

[Jim Koepke]

My first choice would be a compass plane like a Stanley #20 or #113.

A round bottom spoke shave would be my next choice.

One cuts like this it usually works best going from the outside to the center.

I would make the cut with a bandsaw.

jtk

[george wilson]

I take it you don't have a bandsaw. Any hand held jig saw(properly called a bayonet saw). A coping saw will do. I have cut out curves like that with a sharp draw knife in soft wood,though you can't save the wood in the curve that way. A wooden block,planed to nearly that curve,with coarse,then finer sand paper will clean it up if you haven't a curved spoke shave. If you have a spoke shave you don't mind altering,you can usually easily file the cast iron sole to make it curved,and buy a straight one to replace it later on.

[Matt Sauber]

Sorry - should have qualified my questions a bit. I prefer to use all hand tools and to do things the "proper" way if there is one. I'm actually going to buy the tools for this job - I don't own a compass saw or a spokeshave - so "in-a-pinch" doesn't really apply to this situation because I'm going to buy what I need.

This is going to be in QSWO, too, if it matters.

[george wilson]

What is a QSWO ? I worked by hand for 16 years on instruments being in a museum. But,when it came to special rush jobs,like the cider press, I got it done however the best way was.

[David Posey]

A compass saw should be fine for that, but I find it easier to work to closer to the line using the technique Mr. Pierce describes above. If you use the saw cuts/chisel technique, make sure you aren't trying to take off too much wood at once if you're using a species that is prone to splinter.

A compass plane is nice, but they tend to be expensive, so I wouldn't purchase one unless I planned on using it for a lot of other projects. A round bottom shave should give you good results. You might even be able to use a flat one depending on the radius of the curve and the length of the shave's sole. If you have the small contour planes from Lee Valley, that would be another option. They have flat soles, but they are very short and have nothing behind the blade.

[Matt Sauber]

What is a QSWO ?

Quarter-sawn white oak. I only mentioned it because your reply said you use a draw knife in soft wood.

[Jerome Hanby]

Bow saw to the line then a Compass plane or Spokeshave to clean it up?

[Zach Dillinger]

Bow saw to the line then a Compass plane or Spokeshave to clean it up?

+1 on this. If you don't have a bow saw, you could use a drawknife or a hatchet to chop down close to the line, then clean up with a spokeshave / scrapers. Lots of different "right" ways to do this.

[Jonathan McCullough]

I think a flat spokeshave would probably be just fine. The radius on that doesn't look tight enough for it to make a difference. The soles on round spoke shaves are just small enough to make them a bit fiddly, and if you're going to buy tools you should probably have a flat spokeshave anyway. You can get pretty close to the curve by making a series of horizontal cuts approaching the curve, chopping the sections out with a chisel, then getting even closer with a coping saw and finishing with a spoke shave.

[Prashun Patel]

Everyone has their favorite method for smoothing. I prefer to use a flatbottomed spokeshave and a coarse rasp. I prefer flat to roundbottom on the spokeshave bkz it registers better and smooths 'waviness' better. The rasp is good because it doesn't care about grain direction. You'll have this issue right at the apex of the curve. The shave will require you to come in from either side to the apex. The rasp will allow you to go right thru the arc.

[Bill Houghton]

The methods suggested would work for the roughing out. One other possibility is cross-cutting every few inches from the waste side close to the layout line, splitting the waste out with a chisel, and then smoothing. Like this:

222873

For the smoothing, definitely a spokeshave. A compass plane would be the fanciest way to do it, but might be hard to justify unless you plan to do a lot of this kind of work.

[Bryan Schwerer]

There is a company called CME Handworks that sells a very reasonably priced bow saw in many sizes and configurations. You can find them by Googling them. They have a store on an auction site prohibited from being linked here. I have the 12" and like it quite a bit. I have used it to cut curves in 3/4" QSWO. Its not as fancy as the Gramercy, but it has nice handles and a sharpenable blade.

[Jack Curtis]

That's exactly how I do it, too.


The methods suggested would work for the roughing out. One other possibility is cross-cutting every few inches from the waste side close to the layout line, splitting the waste out with a chisel, and then smoothing. Like this:

222873

For the smoothing, definitely a spokeshave. A compass plane would be the fanciest way to do it, but might be hard to justify unless you plan to do a lot of this kind of work.

[Jeff Wittrock]

Coping saw and flat bottom spokeshave will do just fine. Depending on how careful you cut with the coping saw, you may be able to forgo the spokeshave and just clean up with sandpaper. I'm notoriously lazy when it comes to using my coping saw and just use it to come close to the curve I want, then shape with the spokeshave. Spokeshaves are fun to use, but coping saws not so much (at least to me :) ).

[John Coloccia]

If I were going to cut it by hand, I would probably start by making facets. First I'd make two cuts and take out a triangle from the middle. Then I'd make a couple more cuts and start approximating the curve with straight lines. Then I'd probably just grab a spoke shave, rasps and scrapers and just quickly finish it off. It's a small job if you just get all that waste out of the way first.

Nothing wrong with using a coping saw too, if you have one. I just think it would be pretty slow going. if you had a nice bow saw with an aggressive blade, that might be ideal.

[Jim Matthews]

The methods suggested would work for the roughing out. One other possibility is cross-cutting every few inches from the waste side close to the layout line, splitting the waste out with a chisel, and then smoothing. Like this:

222873

For the smoothing, definitely a spokeshave. A compass plane would be the fanciest way to do it, but might be hard to justify unless you plan to do a lot of this kind of work.
This is the method I have used. I used a concave Japanese plane (http://www.dlws.com/Hand-Planes/japanese_curved_bottom_planes.htm) for the job. Quarter sawn White oak is pretty tough stuff; a bowsaw with a decent (new and sharp) blade will make the turn, but they're trick at first.

[John McPhail]

My vote goes for turning saw followed by a shave. Or a circular plane.

[Zach Dillinger]

Like was said earlier, the question I'd ask myself is if you want to save the chunk of waste wood, or if you just want to get through it. If you don't want to save it, cutting kerfs at regular intervals then popping the waste out with a hatchet would be extremely fast. If you want to save the waste wood, about the only way you can do it is with a coping / bow saw. If it were me, I'd saw the kerfs and pop the waste with a hatchet like I said earlier.

[lowell holmes]

+1 for Bill's suggestion.

That's how I learned to do it. A spoke shave works well.

[Steve Branam]

Another +1 for the kerf-n-chisel-n-spokeshave method. I've used it before, on rosewood. Use the chisel bevel down to allow you to pivot it as you sweep down the curve. Paul Sellers, in his new book and DVD series, makes an oak side table with a curve like the one you want to make, using this method. He says a flat-bottom spokeshave will allow you to go as tight as a 9" radius. The one you show can be done with flat bottom without any trouble.

The one really strong piece of advice I would give, since you're planning on buying the tools needed, is to get a really good spokeshave. I have the full range, from cheap modern Stanley, to Lie-Nielsen Brian Boggs spokeshave. The Stanley chatters like mad no matter what I've done to try to get it to work better. The LN is smooth as silk. The extra investment in the LN is absolutely worth it at 5-6x the cost of the Stanley, a joy to use. A poorly-performing spokeshave is extremely frustrating, you just want to throw it across the room.

There are good antique Stanleys I've seen people use, just be wary of the modern cheap ones. There are also many antique wooden ones available, but they vary a lot in condition.