finished the deck stringers which quite nicely started to show the shape of the boat. This evening we completed the bent frames of which there are four. We also added some bracing to the frame in strategic spots . For a more complete discussion on that see boring stuff below for excessive detail and ramblings, if you want to. We are now ready for varnishing and canvas. Looks like a trip to the canvas store is next.Boring Stuff:
When flexing the newly assembled frame I noticed a strange behaviour in the movement of the frame. I was of the false belief that once the ends of the stringers, hog, and gunwales were fastened to the end-posts that the flexing of the entire unit would become fully rigid which it did to quite a large degree. What I continued to notice though was that if I pushed down or up on either end of the frame that the opposite end would go up or down in the opposite direction, sort of like one of those manual reaching devices you see in supermarkets that has a handle grip that you squeeze at the near end and which activates a grabber at the other end.
I realized then that the stringers and frames not including the end sections between either end-post and the next immediate frame, actually acted like parallelograms and moved a bit and the stringers are not entirely rigid and will also flex. To reduce this motion further, we added cross braces
to stringers in one section between frame 8 and bent frame 9. This is shown in the second picture. This should solidify the structure much more however, ideally to make the structure fully rigid would require these types of cross braces on all spaces between the middle stringers and frames. That will make for considerably more work and time delay which we really can't afford right now.What this will hopefully do is stop the transfer of motion from one end to the other. What can still happen is the flexing between all the other frames, although because the joints are glued and screwed and thus will resist any torsion in the joints this should be much reduced.
Tomorrow when the glue will have set, I will see if the aforementioned behaviour has stopped or at least diminished.
A bit of the similar motion could still be observed this morning though it was much reduced. I figure the canvas covering should also stiffen up the rest of it quite well.
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