Wednesday, 8 December 2010


the stringers we use are all sitka spruce from robbins timber in bristol.  they come in a lenght of ca. 5500mm ready machined to a thickness of 35x25mm and in good quality with very few defects and nice straight grain.   we only have to thickness them down to 35x22mm and scarph them to the required length. before scarphing the lengths together we coat them in epoxy and round off the corners that are going to be facing inwards.  doing this before scarphing makes handling much easier.


we find the quickest way to coat a lot of stringers at once is to clamp them flat together, apply resin with a roller or brush and take them apart once the epoxy is gelled so they do not get bonded together.  don’t wait too long… we coat on face side (35mm) first, coat the opposite 35mm side, then round of the corners and do the rounded side at last. the second narrow side is left bare and gets a quick saturation coat before the planking sheets get glued on with spabond.


routering the corners where easy on a simple router table set up but even easier freehanded with this priceless little fella :


for the scarph joints we used a 1:12 ratio which were easily cut on the radial arm saw with a little jig.


clamping them together in a jig with spabond from sp systemsDSCN7086

…and out come enormous lengths of spruce …DSCN7088

…with a nearly invisible joint line. DSCN7089

shame that none of that wood will be seen in the finished boat…

1 comment:

  1. Hi,
    I am now on a ecopower 550- Bernd's power cat as a studywork, before building something bigger. Duo105 looks really nice project. Could You write, why have You choose this project? Whay is Your opinion about Duo105, quality plans, etc, especially as a proffesionalist which You are. It would be very helped for me, to know Your opinions.