The next step in making my pochette, or travel violin is to bend the ribs. Last time I had cut them to length and width. I then soaked them in a tub of water for four days – yes it’s a brutal thing to do to timber, but that’s nothing to what was coming next.

The big question was how to bend the ribs around a fairly tight right-angle turn without breaking them. After a bit of reading around I decided I needed a bending iron and strap. You could spend a bit of money and buy them.

Here’s how I did it. I took a piece of galvanised water pipe and held it in the vise. I then cut the ends off a soup tin and then cut it up the middle so I could open it out flat with a pair of tin snips. Then I used a portable propane gas torch to heat the pipe – after making sure there was nothing flammable in the vicinity.

I then took up one of the ribs, made a pencil mark where I wanted the bends and positioned it between the tin and the hot pipe, keeping my hands clear, and then pressed it against the pipe moving it along about a millimetre at a time. You will hear a hissing noise and that’s a good sign – the water in the wood is turning to steam and steaming the fibres, allowing them to crush on the inside radius, while the water soaked outer ones remain flexible enough not to break – provided they are backed with the tin.

The result is a straight rib with two right-angle bends

And I then clamped the two ribs against the mold where it will gradually dry in shape over the next couple of days. The reinforcing strips will be bent the same way.

When dry I will glue them up ready for the top and bottom plate that still need to be shaped. More on that next time!

You can see earlier posts on this topic:

Pochette – second step

Pochette – first steps 

Cheers
Jerry

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