Finely Strung

At the beginning of the year, in their Tools and Shops issue, Fine Woodworking included a short piece about some violin-making planes that I had made. Since then, several people have asked about them, and how they are constructed. A recent request prompted me into writing down some instructions and, in the hope that they might be useful to others, I’m going to post them here.

A few of these planes are shown below with a Record No 4 in the background to give a sense of scale.

Side view

Three quarters view

Close up view of wedge

I’ve used a variety of hardwoods: box, cherry, elder, hornbeam and beech and made a variety of shapes and sizes for different tasks. The longer plane lying on its side in the foreground is for shaping violin cornerblocks, for example, while most of the others are for the final stages of arching the top and bottom. Some of these have flat soles for planing flat or convex surfaces; others are gently rounded both across and along the sole and are used for refining concave areas of the arching.

The design is extremely simple as from the photographs of this little plane, made of elder, show: just a body, a wedge and a blade. It’s quite possible to make a plane like this from a solid block of wood simply by chiseling out the required shape. But I’ve found that it’s easier and quicker to adapt the method James Krenov describes in his book ‘The Fine Art of Cabinetmaking’ for making much larger planes. Essentially, the idea is that you saw two slices off the block to make the sides of the plane, shape the bed and throat from the middle section, and then glue it back together.

Here’s an attempt at step by step instructions.

1. Find a suitable blade, around 0.5 inch inches in width and 2 to 2.5 inches long. It’s possible to make one out of an old chisel blade. Another idea is to use a blade that once was part of the set that accompanied a combination or plough plane (these sometimes turn up in second hand tool shops having parted company from the original tool). Or you can buy a new blade from a supplier of Ibex or Herdim violin planes.

2. Now you need a small block of wood, preferably sawn on the quarter. Box, holly, elder, hornbeam, fruit woods and beech are all good. Plane all sides accurately square, though you need not worry about the endgrain faces (diagram, step 1). Then saw it into a sandwich (diagram, step 2) making sure that the layer in the middle (the filling of the sandwich, as it were) is a little wider than the blade you have chosen. Plane the sawn surfaces, keeping them square so that you will later be able to glue the sandwich back together without visible glue lines. The final width of the filling of the sandwich needs to be just a whisker greater than the blade.

Diagram of steps in making a finger plane

3. Saw the central section (the sandwich filling) across at 45° and 85° to make the mouth and throat of the plane (diagram, step 3). Keep the wedge-shaped waste piece because it will be useful later. File the 45° surface smooth, flat and square.

4. Glue the sandwich back together, adjusting the distance between the two filling pieces to give a tight mouth (diagram, step 4). Clamp up and allow plenty of time for the glue to cure.

5. Clean up.

6. Try the blade in position. You will probably need to plane something off the sole so that the mouth is just wide enough for the blade to peep out. Bear in mind that if the sole of the plane is going to be curved, the width of the mouth will initially be wider at the sides of the blade and you’ll eventually need to adjust the mouth to an even width by enlarging it centrally. So keep it on the tight side for now.

7. Plane or file the sole to the desired profile. This is most easily done by holding a block plane upside down in the vice and moving the workpiece (ie the plane you’re making) over it in the same way that a cooper’s plane is used, though on a much smaller scale – see photograph.

Using a block plane in a vice

Jig for holding wedge while planing

8. Rough out a wedge. A simple jig like the one in the photograph makes it easier. I like to use a wood of contrasting colour and, if possible, to include a streak of sapwood. But that, of course, is just a whim and of no functional importance. Make the wedge overlength to give leeway for later fitting and leave any fancy carving of the thick end until after the fit is perfected.

9. Put the wedge and blade into position and estimate where to drill for the crossbar that will hold them in place (diagram, step 5). The position isn’t critical but, if the bar is placed too low, it may tend to obstruct shavings as they emerge into the throat. I’ve found that placing the bar about half way up the finished plane works well. Measure the combined thickness of the blade and wedge at this point. Then use a mitre gauge to draw a line on the outside of the place corresponding to the position of the bed. Scribe a second parallel line in front of it (ie towards the toe of the plane). The distance between the two lines should correspond to the combined thickness of the blade and wedge. Draw a third parallel line 1.75 mm further forward again. This is to take account of the 3.5 mm diameter of the cross pin. Half way along this line is the point to drill. While it’s good to get this point placed as accurately as possible, don’t worry too much because you’ll be able to accommodate any inaccuracy by adjusting the wedge.

10. Drill a 3.5mm diameter hole centred on the position that you’ve just marked using a drill press. Before drilling, fit the waste piece that you’ve saved tightly into the gap between the sides of the plane. This will minimise breakout.

11. Turn a short length of hardwood to a diameter of 3.5 mm. Or make it using a dowel plate. Glue into position and trim it off when the glue is dry.

12. Using a coping saw, saw out the curve of the top of the plane. Refine the curve with a knife or file.

13. Then there’s rather a lot of fiddling about to do. Thin the sides of the plane. Adjust the length. Curve the ends. Fit the wedge. File or plane the final profile of the sole and then adjust the curve of the blade and the throat of the plane until you’ve got a tool that does exactly what you want it to do.

14. Obviously, the dimensions, bed angle and other details of the plane can be altered to suit your own requirements.

I’ve no doubt that there are many better, faster, easier and more ingenious ways of making finger planes than this. If you know of them or invent them, please let me know. In a later post, I’ll try to give a bit more detail and discuss modifications and refinements. (See here.)