The final cutting

The final cutting for building a bamboo fly rod

EXCERPTS CHAPTER IV

The triangular rough strips should all have the same cross section, and the final cutting is intended to bring them all to the required shape.

We will then have six strips which when lightened, assembled and cemented together, will form the finished hexagonal component, either butt or tip.

An adjustable metallic form called a final planing form is then used to transform the rough strips into the final planed ones.

THE FINAL PLANING FORM

This consists of two metal bars tied together with sliding struts and having screw adjustments to enable the gap between the bars to be set at will.

planing drilling

Each bar has a 30 deg. chamfer from the vertical axis on the inner side. The two chamfers form a groove defining an equilateral triangle of which the lower fictitious corner is situated between the separated bars whilst the upper side of the triangle is situated above the gap and parallel with the top faces of the bars.
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Building the planing form

You start with two rolled mild steel bars 1.5 meters long with a 20 X 20 mm cross section.

Every 10 centimetres a sliding rod links the two bars together with an adjustment bolt and a locking bolt in order to set the space between the bars. . The first brace/screw set will be placed at 5cms. from the form end, followed by another at 15cms. the third at 25 and so on. You will then have between fourteen and fifteen adjustment sets which are enough for the usual cane length. (90 to 130cms. for each element (sketches 4.1 and 4.3).

It is possible to consider longer or shorter forms; nevertheless in practice 150 centimetres corresponds to every case to a modern cane made in split bamboo. The bars are retailed in three meter lengths by the wholesalers. Have them cut in two even lengths, as the bars are often longer than three meters and you would have a form slightly longer than you want.

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The Chamfering tool

chamfering tool

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So, as Daniel Brémond advised me, I decided to mill the chamfers myself in my planing forms. The process is quite simple although it is time consuming as the form only allows the groove to be gradually channelled out. Use a triangular file (medium bastard grained) set in a wooden block (sketch 4.4).

Milling-chamfers

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ADJUSTING THE FORMS

The depth gauge

chamfering tool
4.7 The depth gauge upon the form.
The dial indicates 6.10, that is to say 3.9 mm of depth

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THE STRIP CUTTING : PLANE, FILE, SCRAPER

After having exclusively used the various planing processes, I had to conclude that there is not a problem of choice but tool compatibility.

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The scraper

The word « scraper » is probably not convenient, as all woodcrafters know that this word designates a special tool. Nevertheless there is no other term available, and the tool of which we speak about later follows the same principle just as well, but have no rough edges.

Nowadays I exclusively use the scraper for the final planing. This came from a thin cutting blade from a lathe tool. I have some made in mild steel and others made in carbon steel. I use them to refine the surface after the first rough planing with the file. The blade of the scraper creates an even wood shaving.

scraper
4.9 A scraper (carbon steel blade) fitted with an aluminium handle.
Note the mark indicating the exact place of a tip head for a 3.65 m salmon rod.

For the very thin tip tips (strip with a thickness of 0.6 to 1 millimetre) be careful not to break the strip by pressing too much on the scraper angle.