December 28, 29019
With family in town, I managed to make it to the boat today by nearly 3 o'clock with at least one item to get through - gluing up the blank for the new bow cap, part of the deck rail system. The original was well-worn, with significant checking and dry rot. The piece was almost 2" thick, and over 8" in width. I culled a piece of of the thicker teak from the remaining supply, and with a circular saw cut to lengths that I would need to glue together to create the width needed for its replacement. Examining the original cap, I noticed that it was also fabricated in this manner. After cutting the two pieces I jointed their edges to be glued up.
I wiped the two halves down with a solvent to clean any remaining sawdust and teak oils from the surfaces, and then mixed an ounce of resin to first apply to the gluing surfaces to wet them out, and then thickened the remaining resin with 406 colloidal silica. I applied the thickened epoxy across the gluing surfaces, and on a sheet of plastic then joined the edges together. I placed two clamps on the blank to pull the two halves tight, forcing good squeeze out. I placed another small bit of plastic on top of the blank, and with an off-cut piece of piece of teak clamped across the blank to keep the two halves in plane.
From this blank I will be forming the new bow cap - more to come.
I spent the balance of my time in the shop today working on the boat's new tiller. In the previous work session I had created three strips of quarter sawn white oak, so today I replicated those dimensions and created four strips of teak. The assembly will be to alternate teak and white oak strips in the final lamination.
After sanding each side of each strip of wood, I laid them out in the order I liked, using the natural curves of the teak to my advantage. I also compared the width of the seven strips of teak and white oak to that of the original, and it was grossly too thick. I removed one strip of teak and one of the white oak strips, and this new dimension was pleasing in form.
I tested how the wood strip assembly wood take the forms of the tiller template and was satisfied in how fairly easily it took to the form. I am hoping that post-cure there will not be much spring-back after removing it from the template.
I then laid out a sheet of plastic and placed the wood strips on top. With each one, I ran an acetone-dampened rag down all surfaces to remove oils and sanding residue. Next, I mixed two cups of epoxy resin: one 'neat' (with no thickening agents, and the second one thickened with 406 colloidal silica. Alternating application of the two epoxy cups, I applied the neat epoxy and then the thickened epoxy to each of the gluing surfaces. With all surfaces having epoxy applied, I assembled the tiller lamination and then folded one of the sides of the plastic sheeting over it.
I placed the assembly into the tiller template, and then folded the other side of the plastic over. Working from a couple spaced out clamping blocks, I alternated tightening clamps on the blocks, pulling the tiller assembly tight into the block and forcing the form of the old tiller onto it. I slowly worked all clamps until I was tight across the length of the tiller lamination. I used a small block of wood and a hammer to tap the lamination into a flat plane, ensuring that no single strip of wood was out of line with any of the others. In the coming days I will remove the clamps and clean up the cured epoxy squeeze out, and begin to shape her for final form.
Total Time Today: 1 hr (tiller will not be billed time and materials)
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