Shop made Roubo-esque crosscut bow saw

13/4/2015

This is the second of a working set of bow saws that I am building at present. I decided to use Andre Roubo’s plates as inspiration for this one. If you are interested in this brilliant book by Lost Art Press, check it out here. The final picture in the series below is what I was aiming for.

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My bench while all this was going on.

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In terms of wood, I thought Assegaai (Curtisia dentata) would be perfect given it’s strength and resistance to splitting when flexed. In the pictures below you can see the pieces I selected. You might be able to see how the grain is running off to the side at one end of both pieces destined for the cheeks. I specifically chose it like this to follow the curve of the top end of the cheek, hence improving the strength.

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I used dividers to get a sense of the proportions of Roubo’s saw. One fixed measurement was the length of the saw blade (700 mm) as bought from Dieter Schmidt. I applied the proportions to this starting point to establish the length and width of the cheeks. In terms of the shape I simply drew something that followed the grain and added some artistic je ne sais quoi.

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I drilled and chopped the mortises in the cheeks prior to shaping.

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With the stretcher in position I marked out the correct location of the holes for the cross pin (6 mm or ¼” steel bolt in this case)

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20/4/2015

These holes were tapped and countersunk.

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Next step was to cut the kerf for the blade.

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I used the bandsaw to do the rough shaping.

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The lines to guide the next phase of shaping were drawn as shown, using my finger as a fence. It is quick and easy.

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The rest of the shaping were accomplished with spokeshaves, files and a card scraper.

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I used the same piece of Tamboti as mentioned in my previous post for the spindle of this saw. It was simply a bit bigger.

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A quick test fit. I really hope Brian Eve (Toolerable) does not get on my case again with regards to the string I used. I do not even know what this stuff is called, but it is cheap and available so that is what I went for.

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Tung oil treatment.

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Don’t you think Assegaai is exceptionally beautiful? I do. This saw hums through African hardwood. Viva Monsieur Roubo!!

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My next project will be a Fidgenian frame saw. The other saw I have built already is a 12″ bow saw. Go here if you want to take a look.