Friday 6 April 2012

Transom

As I write this, time has passed so thankfully I can't recount the entire fiasco that was building my transom!  You see I had some nice 2 1/2" by 9" timbers which I thought I could resaw and get two board out of one.


That seemed to work fine, although I wasn't convinced that the thickness of the two boards was uniform. No matter that was what planers are for...except my planer was only an 8" model.  So armed with my new #6 foreplane, I went about flattening the boards.  I had read in John's book that this was good practice/exercise, so fired up with these encouraging thoughts, I set about creating heaps of wood shavings.  Man I was having a ball - yes I was a real boat builder at last - none of that modern noisy machinery, I could see myself swelling with pride as I recounted how I had hand planed that lovely highly polished transom to the admiring onlookers...

Well, after I had one side nicely flattened, I noticed that the board was beginning to warp, and before long I had the distinct impression that I was carving a wooden propeller rather than a flat transom!  Moreover, I had neglected to keep tabs with the width and so I ended up with boards too thin for the finished transom.  So out with the bandsaw again, and this time I laminated a new piece onto the original board and invested in a new 12" planer, and voila - a (reasonably) perfectly straight transom of the correct thickness. phew...

I elected to use biscuits joints as I had a biscuit jointer and had reasonable confidence in my ability to accurately joint the boards.  I had visions of routing out splines etc., but wasn't convinced I would get the accuracy I needed.
I did however elect to use the technique which John describes in his book to get two boards perfectly edge matched using one baton and a flush trim router.  It worked a treat and so hopefully the glue lines will not be too noticeable when the transom is finally varnished.

My next step was to mark out the shape of the transom onto the jointed boards.  This was trickier than I had imagined.  John has supplied a fully developed transom in full size scale in the plans - for one half.  So one half of my transom will be correct at least!  Flipping the plans as John describes in GLWB and pricking the the other half of the transom boards using the existing holes proved more difficult, so I erred on the side of caution and cut to the outside of the line.  Later I made up a large "compass" and used it to ensure than my marks were symmetrical on both sides. With hindsight, I would take this approach again, as I was able to take accurate measurements from the FSP and transfer to both sides of my transom.

Carving the bevel on the transom was quite tricky.  Not having any prior experience of reading the plans, it was not entirely clear to me how the bevel should finish.  I had read elsewhere on Dave's SS 12.5 blog that he had difficult cutting the notches on the transom, so he recommended waiting until it is affixed onto the jig and you can fair out the bevels using batons.  I had elected to take the option of a curved transom rather than notching the transom.  This means using Dory gains at the transom.  I did take the initial bevels off using the bandsaw, as John describes, which I thought was quite brave of me! But as luck would have it I didn't screw up and so then I finished off the bevel with my block plane, spokeshave and finally Stanley Surform.  I'd love to relate how I expertly carved the wood with my spokeshave, but to be honest, it only made a horrible scratching noise as I dragged and pushed it over the the timber, so my Surform won the day!

Subsequently, I spent some time researching how to use (and tune up) a spokeshave, and now can manage to get it to shave really nicely - certainly a tool worth persevering with until you get the knack.