January 1, 2019
Well, Happy New Year, dear reader! And what a day to be working outside on a classic sailboat!
I went straight into the continuation of the mast step / mast support beam rebuild by water-washing the amine blush from the cured surfaces, drying, and then sanding the work area to prep for further lamination. The task today was to layout a layer of 1708 glass across the integral support beam, and to assemble the mast step itself, comprised of layers of G-10 fiberglass board.
I sanded the opening on the coach roof to my satisfaction, and then thoroughly vacuumed and solvent-wiped the surfaces in preparation for further lamination.
With existing G-10 board that I had in my inventory, as well as a board purchased specifically for this project, I laid out, measured, cut, and prepped the various boards for construction of the mast step.
The basic assembly of the G-10 boards for the mast step is pictured below. I narrow piece would serve to fill the recessed opening in the integral mast support beam, two slightly wider pieces would bridge the remaining recess and back to the aft edge of the forward hatch frame, and lastly, a larger piece would cover the sub-assembly serving to tie it all together. I would fill any gaps with thickened epoxy, creating a solid foundation for the mast step. Below this new assembly of G-10 boards, as readers will note from earlier work, I had encapsulated additional G-10 boards. The mast step will essentially be a solid foundation of fiberglass and epoxy resin - firm foundation for the mast.
Prior to wetting out the work area, I applied some 4" wide 1708 biaxial tabbing material, and marked it for a cut line so that the glass would lay flat in the recessed opening.
After I cut the initial layer of 1708 cloth, I wet the recessed opening with neat epoxy (epoxy resin without any thickeners). I then made my way back to the shop and wet out the 1708 biaxial itself. With the remaining epoxy resin in the mixing cup, I added 406 colloidal silica and 407 low-density filler to create a thickened epoxy. Using a squeegee, I applied a very thin layer of this thickened epoxy across the already wet surfaces in order to fill any small voids in the surface. With this done, I applied the 1708 biaxial layer, and applied a layer of peel ply, or release fabric, to the outboard sections. These sections would see no further work for the day, so I carefully applied this material to exclude the center portion of the mast support beam in order to continue to construct the new mast step. The peel ply / release fabric creates a surface free of amine blush and textured so that one can continue laminating without the need to first water-wash and sand the surface.
I moved forward with the final task which was to assemble the mast step. I applied a layer of thickened epoxy to the bottom surface, again using a combination of the 406 and 407 thickeners. I pressed the first G-10 piece in place, ensuring all gaps were filled in with the thickened epoxy. Next, I spread a layer of thickened epoxy on the top of the first piece of G-10 and then placed the next two G-10 pieces in place comprising the second layer. Continuing the sandwiching making process, I buttered the tops of the second layer of G-10 pieces, and then set the third and final larger piece of G-10 in place. I worked my way around the assembly to ensure all gaps were filled and that no unnecessary thickened epoxy remained on the surface that would require sanding work to remove.
Finally, I covered the assembly with additional layers of release fabric in order to minimize the subsequent prep work for additional lamination. I'm making good progress on closing in the coach roof and other deck areas. With some additional laminating work on the mast support beam, I will be ready to replace the core on the coach roof.
Total Time Today: 3.25 hrs
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