Bow-making course with Helmut Riebl


In this presentation, I am going to show the process of the first bow I have made. As part of my research about historical bow making, I found it important to have some practical experience. For this, I found Helmut, who works in The Hague, and as he is a musician as well, he finds it very important to share his knowledge and 15-years experience with other musicians. He has a well-structured, 10 days course, which contains 8 days of bow-making, and 2 days shopping. This means that we go together to select and buy wood, and tools what I can take home at the end of the course, so I can continue with an other bow at home.

 In the course, we copy one bow as close as possible, so we have a reference to work with and then to compere with when mine is ready.

 

First day:

-          Selecting wood: Massaranduba – South American hard wood with high (a little bit less then snakewood) density. We chose this wood, because it is a bit easier to work with this wood than with snakewood for the first time, but they have similar characteristics. Snakewood cracks very easily for the smallest mistakes.

-          Making a blue-print: we made two drawings – one with tension and one without tension with all the exact measurements. Height and width in every 10 cm, measurements of the frog, distance of the hair and stick.

-          Making the frog: from the same wood. The end of the day, the basic shape of the frog is ready with extra 1 mm.

 

Second day: goal is to finish the frog and to get close to the measurements of the stick (square).

-          Frog: making the canal for the hair. The two sides has to be very symmetric and cannot be too thin. The important part is where the hair leaves the frog, that has to be the highest point and very round, so the hair lies on it nicely. The rest of the frog is design.

-          Stick: we can write the numbers on the side of the stick, so it is easy to follow (with very regular measuring!!) how much wood we have to remove. I worked with wood plane, first time in my life, it took time to get used to it. It is very hard to make clean and flat surfaces. The bigger the tool, the easier it is to avoid mistakes and small waves.

 

Third day: goal is to reach 1 mm extra from the final measurement from each side of the stick.

-          When we are closer to the final measurement, better to change to sand paper, it is easier to control.

-          Important to keep the sides flat and straight

-          When it is ready, I polished the stick: with sandpaper, starting with 80, finishing with 12000. When it is nicely polished, it is easier to see the mistakes and little waves on the surface.

-          If there is a ‘belly’ in the stick, it is a common solution to bend the stick back with heat.

-          Starting the tip: I had to draw the shape of the tip on the wood. There are two important parts: the distance between the hair and the stick, and the place where the hair leaves the tip. The rest is design, but of course important for the balance.

 

Fourth day: finishing the tip

-          Final shape of the tip, important to keep it symmetric, and to check the height.

-          The place where the hair will sit cannot be too thin, that will make it very difficult to make the hole.

-          For the shape of the curve, I used a small machine.

-          Working on the stick: with a sandpaper, reaching the final measurements of the stick (still square).

 

Fifth day: finishing the tip, and making the octagon shape

-          Tip: I could design it as I wished, only the width around the place where the hair comes out is important.

-          Important to take care that the end of the tip is exactly the continuation of the stick.

-          Octagon shape of the stick: different options to make it

Blade

Plane (very hard to control)

Sandpaper (for the end)

Little Japanese hand tool

-          Removing the edges until it becomes equal octagon

-          After it is ready, polishing the stick, so I could see again all the little mistakes which had to be corrected

 

Sixth day:

-          After the octagon, removing the edges again, making it equal. Then removing those edges too, until it becomes a ‘chaos’. This is the best with the non-sharp part of the blade. Contining until all the edges disappear, and the stick becomes round. It is a long and slow process, requires a lot of patience. The best is to touch it, and when I didn’t feel any edges, then it is ready for the final polishing.

 

Seventh day:

-          Practicing the hole for the hair!

Using the small hand machine and chisel

The angles of the sides have to be the same!

The hole can be made most easily by the hand machine. Has to be big enough for the know of the hair!

-          Wedge: has to fit perfectly, cannot be gap at all

 

Eight day:

-          Finishing the frog, so it fits completely to the stick

-          Making the hole on the stick. The important thing is, that the holes are big enough to make space for the hair, but the walls are not too thin.

-          Selecting hair: around 120-125 hairs in a cello bow, depends also how thick they are. I had to select the good hairs, which feel smooth and more or less the same thickness.