World’s thickest transom.
Having spent half my retirement funds on the Huon for the transom, I have been reading and re-reading the plans, sleeping on it and re-reading again. I can’t afford to get this wrong.
In order to ensure that my transom blank was large enough for the job, I had the FSP scanned and printed on transparent paper. I then flipped the transparent copy, laid it on the transom FSP and traced the Starboard section, giving me a FSP of the whole Transom. see pic.
As luck would have it, a sharp, fellow Somes builder spied my last blog entry and kindly emailed me, pointing out that my 38mm plank was the same thickness as the design Transom plus Transom Cheeks. Quite insightful, as he is an inches man from the Good Ole . . .
“Leave your plank thickness as it is Pete, and dispense with the cheeks.” he suggested.
So having mulled over that one for a couple of weeks, I decide it was a good idea. The reason I had to mull over it was that it means the inside face of my transom is going to be further forward than on the plans and I needed to work out if that could be accommodated. Conflicts as the engineers say! With some fiddling, I think it can. I’ll need to move the transom support forward on the jig, route out for the Transom Knee and do a fiddle where the Keel meets the Transom.
The good side is that the forward face of my transom will lie on the line of the forward face of the transom cheeks, so I will only need to mark the Transom with that set of lines and the rear face lines.
July 9th. Routing the Transom Joins.
Having managed to get the transom planks flat and sanded smooth, I played around with the two planks to find the most attractive faces and decide which way they looked best together. It was a bit of a compromise, as there is so much birds-eye and marbling in them. But there was an obvious pair of faces that matched. They did come out of the same log.
I then gave the faces a coat of varnish in the hope of protecting them from any epoxy squeeze out. I did this before routing the edges so any varnish dribbles on the edges will be removed by the router before epoxying them together.
To ensure the planks met well, I set up a routing jig as per JB’s advice and took a mm off both planks. What a brilliant technique.
JB's Routing Jig.
However, the boards did not sit together well and I diagnosed the problem was due to my bench having developed a warp . . . despite having flattened it with my router a couple of years ago. Obviously the bench timber is still drying. The wood is Murray Valley Pine (commonly called Cypress Pine, which is a ludicrous names as Cupressaceae [Cypress family] are different to the Pinaceae [Pine family]. It can’t be both!)
So I made up a sled and set about flattening the bench again. Starting at one end, with the router just skimming the surface, I found the router taking of 3mm in the centre reducing to zero at the other end. You can see the cutout in the pic below.
Routing Sled for bench flattening
Now it’s flat. What a difference. And the planks meet with hardly a visible line.
Routed Join. It's there somewhere.
13th July Splining the Transom Joins.
My gorgeous Veritas Plough plane, which I bought to cut the spine dados, arrived. I practiced cutting dados on a piece of pine. It took a while to get the technique right, but the real break through was adding a relatively large piece of 10mm ply to the fence to give a much deeper face.
I then bit the bullet and started on the Huon. All went very well, largely, I suspect because the Huon is so much easier to work then pine.
Veritas Plough Plan cutting dado for spline
Having cut the 3/8” grooves 6mm deep (The plane came with imperial size blades. Come on America, it’s time to change gears), I ran a piece of Celery Top Pine through the thicknesser and made a batch of splines.
How delighted I was when I slid in the splines, pulled the planks together and found the splines took the slight bend in the planks out and the faces came together almost invisibly.
Beer O’Clock.
Transom. Splined but not glued.
Transom Spline
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