The Tongass!
Step 2) Making the stringers
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(Click pictures for full size image)

Original beam material Here's the original beam material, 14"x1-3/4"x17' Versalam LVL. For the uninitiated, the correct beam construction is a laminate of 1/8" plies. This product is made under various trade names and may come coated with wax for protecting the beam at a construction site. Try to get the type without the wax coating so you can avoid issues with epoxy bonding later. Note that Microlam and other beams made from wafers, chips, particles, or glued-up layers of dimensional lumber such as 2x6's are not the same thing. Look for the one made with the 1/8" plies that are full width as shown.

My beam was neither flat (it had a bow in it), nor square (one end was wider by 1/4"), nor cut properly to length...more info on correcting these things below. Finally, note that the instructions call for a 14" wide beam, but Renn says you can use two 7" wide beams instead if it saves you money or seems easier.
The first thing to do is to rip the beam lengthwise down the middle with a 12-degree bevel. Make sure you cut this angle right. With the stringer on edge, as installed, the bevel defines the deadrise angle of 12 degrees off the horizontal. I carefully found the center of the board at several points, then snapped a chalk line along the best average. Because my beam was not of consistent width, this gave me the 'best center'. Next, I used drywall screws to temporarily hold some cedar trim pieces on the wood to act as a guide for my 15A Porter Cable. Setting up to rip the stringers
Flattening the stringers Here you can see that I've run each stringer through my thickness planer to take off the high spots. I removed as little wood as possible so the beam would remain at the correct thickness of 1-3/4". By flattening the beams like this, I could check and correct the bevel angle that I cut into the stringers. Unfortunately, the bow in the original beam resulted in the bevel being 13 degrees, equivalent to about a 5/8" error in height at the chine flats...this must be corrected. I reclamped the cedar to the wood and re-cut the bevels on each, just barely taking off a whisker of wood...barely enough to get the desired 12 degree angle.

Since the inconsistent width of the beam would result in inconsistent height of the stringers, I used my table saw to clean things up a bit. I measured the stringers at several points to find the narrowest width (to be the shortest height when on edge) and set up the fence on the saw to this width. The goal was to remove nothing from the shortest height areas but to bring the rest of the wood down to that height. Note: Run the stringers through the saw with the beveled edge against the fence. In the end, my stringers had the required 12 degree bevel, measured the 1-3/4" thick that they should, and were 7" tall on the wide face. Note that at one point, Renn mentions that the stringers turn out 7" tall, and in another he mentions 7-1/8" tall. I think that's because some beams come from the factory cut to 13-3/4" wide, while others come out at a full 14" or beyond (like mine.)
In this picture, I've marked off vertical lines and the offsets that define the curve which fits the hull. Between each set of marks, I've written the required bevel on the wood. I put a thin finishing nail in each offset point, then bent a batten along the points and drew the curve. Clamps were used to temporarily hold the batten to the nails. Make sure the curved line goes on the side of the beam with the beveled edge. Marking the hull curve
Cutting the bevels on the stringers As an aid in quickly setting a bevel to the desired angles, and to make it easy to set up my skilsaw too, I borrowed Dave Wright's idea of making up a set of blocks cut at the right angles. I used my compound miter saw to cut the blocks. Notice the bevel set to 37 degrees on the top block, and the homemade bevel board that I use for individual sets on the bevel. The bevel board is a piece of CVG fir that has 0 through 90 degrees marked on it as shown.

I highly recommend making these blocks. You'll end up using them to set/reset the saw and to set/reset the bevel several times as you make your various cuts and check the result of your cuts and the planing you do on the stringers as you proceed...very handy (Thanks, Dave.)
I just used my standard 15A Porter Cable to cut the bevels, but prior to cutting them I used a straight edge to draw a line tangent to the curve on the wood, where each of the angles were specified. This gave me a line to follow as I made the cut. The picture shows the unplaned stringer right after cutting, note the flat faces on the curve. Here you can see the 1/8" laminations of the Versalam beam. Saw cut stringers
Finished shape of the stringers Here's what the stringers look like after finishing the shaping work. For the planing, I used a carpenter's pencil to shade and mark the areas that needed to be removed, then planed off the high spots (Bosch power hand plane, set for the finest cut.) This was an iterative step that include a lot of eye-balling, marking with the pencil, and double checking of the bevels at the right points as I went. To make the two stringers match each other perfectly, I first finished one, then clamped it to the other to mark the differences...then went through much the same procedure to plane the second one. Note: Clamp them wide-face-to-wide-face and mark the differences, making sure the top edges of the stringers (facing out towards the walls in this picture) are aligned perfectly, then repeat but with the short faces against each other. This worked very well for making the two stringers turn out to be a) correct, and b) mirror images of each other. I finished the job by routering the top (square) corners with a 1/4" roundover bit and giving the stringers a good 60-grit sanding on all sides except the beveled edges (best to leave these alone...open wood cells from cutting or planing glue better than sanded wood cells since sanding smooshes the cells closed.)
From this point on, I am executing an optional step that Renn Tolman did not specify. I am glassing the stringers with 2 layers of 12-oz biaxial fiberglass, and will follow later with Renn's recommendation on top of this. Note: Renn has you glass the stringer to the hull with 24-oz biaxial, then follows by going from hull, over stringer, and back onto the hull with a smoothing layer of 6-oz woven fiberglass.

To apply the 12-oz biax, I pre-cut four 17' strips of the 12" wide biax tape. I then pre-wet the glass by rolling it out onto plastic that I'd stapled to a couple of 4x8s and used a roller to roll the epoxy in. This stuff uses plenty! While this was soaking, I pre-wet the stringer with epoxy. Then the biax was rolled up (loosely folded) and unrolled along one side of a stringer (laying on its side.) A squeegee and gloved hands were used to press this first side into place, then then...

 Glassing stringers, part 1
Mounting stringers edgewise on sawhorses ...I turned the stringer up on edge and drywall-screwed it to a couple of pieces of scrap that I'd conveniently screwed to the ends of my sawhorses. With the stringer edge-side up, I rolled epoxy onto the top and other side of the stringer and folded the glass down over it. Note how it only comes about halfway down on this side. The second layer of glass goes in the opposite direction, and the bottom half of the stringers will be buried under the fillet and 24-oz glassing that Renn specifies so it is not necessary to carry the glass all the way down.
Notice how the glass overhangs the curved bow end of the stringers. I found it fairly easy to allow it to cure to a green stage like this, then used a SurForm along the edge to cut the extra glass off. Some people like razor blades or Xacto knives, but the 12-oz biax is too heavy for that. I've also heard that a light touch with a rough-grit sander or belt sander will work. I just did it by hand. For the edge area where the glass terminates on the side of the stringer, the Renn-suggested carbide scraper made by Sandvik did a great job at tapering it to the wood. Overhanging glass
Rough biaxial Notice how rough the biaxial is after it cures. The yard can clearly be seen (diagonal lines) as can the rough knitting (horizontal lines) that holds the 2 layers of glass yarn together. This would take forever to sand and fill with straight epoxy...
Here it is after a light sanding with 60-grit on my random orbital. The goal is to take off the worst ridges and sharp points in the knitting (OK) without sanding into the biaxial glass yarn (not OK) Sanded biax
Silica epoxy filled biax And here it is after filling the cured and sanded weave with silica-thickened epoxy. A wide metal trowel made quick work of the filling...nice!! After curing, I sanded the filled weave with 60-grit again, to make sure it was smooth. I went through this entire process with the first layer of glass to prepare for the second, and again for the second layer of glass to prepare for the glassing that will occur after the stringers are in the boat. That's it for these...they're ready for installation into the boat.
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