The Tongass!
Step 3) Making the transom
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(Click pictures for full size image)

Original transom design
Original transom design 		The first thing to note is that I slightly modified the transom design. A friend of Renn's has a 115hp Yamaha 4-stroke and a kicker like I plan to use and had Renn make a minor adjustment for him. Since he is using an always-hooked-up steering link between the main and kicker, he wanted full steering range with motors up or down, or in combination. With the kicker up, the main motor down, and turning hard left, his kicker 'just bumped' the transom cut-out on the left side. Renn added 2" clearance at the top of the cut-out to accomodate his setup. Rather than try it and see, I decided to make a similar modification right now, as I build it. I also think the new cut-out looks nicer.

Before: The top image shows the original transom design with 60" wide cut-out. Notice the vertical sides of the cut-out.

After: The bottom image shows the what I have done with my transom cut-out. Everything's the same, except I widened the top of the cut-out by 2" on each side. The transom top shape was adjusted to match. (Shelves and transom gussets shown so I could double-check that all would fit OK.)
Here's a close-up of the transom modification, as drawn on the wood itself. The vertical line is the original 30" vertical. You can plainly see how I adjusted the top end to the left 2" and then radiused the top.

 Transom cut-out modification
Drawing a camber on the transom I used my spline and spline weights to mark out a 1/2" camber between the transom top radius and transom side. Renn sure got this camber right...the two curves blend beautifully.
The unfinished transom. Bottom edges where the bottom panels and chine flats intersect the transom, and the top of the stringer cut-outs were cut with a 12-degree bevel, wide side of the transom 'up' (to be the inside of the boat...the transom leans aft.) The sides of the transom, where the side panels meet the transom, were cut with a 6-degree bevel, wide side 'up' (also to be the inside of the boat...the transom beam is narrower than the widest beam and the side panels meet it at a 6-degree angle.)

Now that the transom is cut out, I'm going to set it aside for a little while. I need to give my 2x8 a few weeks to dry out (same goes for the 2x8s for the aft shelves), so I'm going to move on to something else.

 The unfinished transom
Gluing the 2x8 onto the transom At this point, I've used the main transom piece to mark out the horn and bottom doublers, cut them out, and laminated them onto the transom. I laminated these on using a gooey mix of epoxy and silica (not so thick it wouldn't flow well). To hold the laminated pieces on, I just used finishing nails and then pulled them back out in the morning...very tiny holes (better than screws.) After that, I fiberglassed the transom 2x8 with 10-oz woven that I had left over from another boat building project...why not? Unless you buy clear vertical grain (CVG) fir, nearly all dimensional Douglas Fir lumber nowadays has some cupping to it, since they now cut smaller trees and there just isn't room to get any quarter-sawn pieces of wood out of it. Same goes for knots...gone are the clear straight samples of fir from our past (don't ask me what I think about old growth in the Tongass Forest being pulped for paper...). To make a more rigid structure, I glassed the outwardly cupped side of the 2x8 and then glued it on (shown) with plenty of thickened epoxy to fill the shallow void under the wood. The inboard top edge of the 2x8 was routered to a 3/8" roundover prior to glassing.
The ready-for-installation transom. Once the 2x8 was cured, I gave the transom a last once-over before setting it aside. In particular, I trued and sanded all edge areas to make them fair and ready for the filling of holes and coating (to be done later.) And most importantly, the V of the bottom panels is partially defined by the V in the bottom of the transom. The flatness of the aft portion of the boat's bottom is a key performance factor, so I took the time to make sure the transom V had equal deadrise angles on both sides and were straight (aluminum straight edge.) A Stanley low-angle block plane made quick work of the minor variations I found. Note: The bottom doubler (below the splash well slot) was also glassed with 10-oz woven...I still had more leftover glass, so I put it to use (not shown.) The finished transom
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