I had other business away from the shop later in the day, so I didn’t plan to attack the primer sanding just yet; in any case, the cold and windy weather yesterday and overnight meant that the shop had been cooler than I’d usually expect during the primer application and cure period, so it may not even have ben ready to sand (I didn’t make a test since I had no plans to sand this day anyway).

After cleaning up the spray gun, which I’d left soaking overnight, I turned to the deck hatch lens replacement.  The replacement lens had arrived, so now I used the old lens as a guide to cut the new acrylic to fit, tracing the curved corners from the old hatch onto the new.  With a scrap of the new material, I compared the color of the new lens with the old; it looked like a good match.

I dry-fit the lens in the hatch frame, where it fit with no problem.  The hatch design as original incorporated an open caulking space between the edge of the lens and the hatch frame itself, so the lens was not a tight fit.  I suppose this allowed for expansion and contraction of the parts in various conditions.

Satisfied with the fit, I spent the remainder of the day’s time cleaning up the rest of the hatch frame to rid it of old sealant.  As usual, old silicone proved challenging to remove entirely, and I relied mostly on a scraper for the job, with some coarse sandpaper to help where needed.  For the new lens installation, the actual adhesion and sealing of the lens to the frame would largely occur on the flat faying surfaces around the frame, rather than the ineffective double-stick foam tape that appeared to provide the bulk of the “seal” in the old design.  I ordered sealant designed for lens installation and would complete the job once the materials arrived.

Over the course of several hours, waiting between coats, I spray-applied three coats of white finish primer on the hull, leaving this to cure overnight.

The fine filler had enjoyed a weekend’s cure time, so now I sanded the hull once more as necessary, smoothing the filler and fine-tuning the primed surface with a finishing sander and by hand.  Afterwards, I vacuumed and solvent-washed the hull to remove dust.

I patched a few areas where the masking tape had been scarred during previous steps, then thoroughly cleaned the shop to remove and settle dust.  Once all that was done, I solvent-washed the hull a final time, this time using the proprietary solvent from the paint system.

With some time left in the afternoon, I took a look at the deck hatch frame I’d removed earlier, and tentatively dove in to see about removing the old lens for rebedding.  The lens was surrounded by a large amount of old silicone sealant, which had been ineffective at stemming leakage, apparently.  I cut out the bulk of this sealant with a knife and 5-in-1 tool, and cautiously tested the adhesion of the lens to the frame itself.  I had no problem getting the putty knife beneath, so I loosened the lens from all four edges, then, from underneath, pried the lens off the two crossbars as well, releasing the old acrylic lens intact.

The old lens had been installed over some sort of adhesive foam-based tape on all the bonding surfaces, plus the sealant around the exposed edge.  This was not only ineffective over the long term, but also left residue of the soft tape behind on all surfaces.  It was easy enough to scrape off the metal hatch frame, but would take much more time on the old plastic lens.  I soon determined that a replacement piece of acrylic for the hatch was relatively inexpensive–it was only 1/8″ thick–and that it would be far more economical, not to mention better in the end, to replace the lens with new rather than waste time meticulously removing the old bedding from the faded old lens, and I ordered the replacement.  My time could and would be better (and unavoidably) spent cleaning up the aluminum frame, which was contaminated with the old silicone and would require some work to clean up sufficiently to ensure good bonding of the new materials.    So with a bit more preliminary scraping to remove the worse of the old bedding from the hatch frame, I called it a day for now.

The high build primer had cured well overnight, and was ready for sanding.  Starting with the counter, I sanded the finish with 220 grit paper on a vibrating finishing sander.  The primer sanded easily with no issues, and the work went quickly as I continued from the port quarter up to the bow, then around the bow and back down the starboard side to complete the work.

I vacuumed the hull and solvent-washed, then went around the hull closely and applied 2-part fine fairing material where necessary, mainly to deal with some sanding scratches beneath the rubrail and some of the hardware, as well as a good-will sort of skim over some of the long-ago-repaired work on the port bow.  Most of this filling was probably not that critical overall, but the benefit of the high build primer is that it helps highlight even the smallest interruptions in an otherwise smooth and fair surface, giving me the opportunity to fine-tune things just a bit.  This was good timing as it would give the filler the entire weekend to fully cure for easy sanding next time.

Over the course of several hours first thing in the morning, I spray-applied three coats of high build primer on the hull, leaving it to cure overnight.

During the morning, I finished up the list of chores required to prepare for high-build application.  This included touching up the hull sanding in a few places, mainly the stem and transom around the hardware, then preparing and setting up spray equipment and hoses, paint supplies, and so forth.  I finished up with a final solvent wash on the hull, this  time using the proprietary solvent from the paint system.

I like to do my spray painting only first thing in the morning for various reasons, so I never start part-way through a day, and I needed the overnight to raise the temperature in the shop to painting level anyway.  So I turned to other things for the remainder of the day.

I started the day vacuuming off the hull, then following with a solvent wash to remove all dust and prepare for additional masking and other prep work.  With that done, I went around the hull and repaired a few places where sanding had damaged the masking tape, especially around the fittings on the transom.

Next, I re-established the location of the waterline (technically the top edge of the bottom paint) at the stem and stern using the reference measurements I’d made early in the project.  Then, I set up my horizontal cross beams at each end and leveled them at the proper height.

With a line strung tautly between the beams, and just touching amidships, I struck the remainder of the line on both sides of the boat in my habitual way, pulling the string closer to the hull in increments and taping it securely so it wouldn’t move, then making tick marks and continuing the process.  This ensures an accurate and planar line between the two end beams.

With the line thusly marked, I masked off just below the tick marks.

Finally, I added some masking paper below the tape to protect the bottom from overspray.

I moved the staging back into position around the hull and, since there was no way I’d be able to complete all the preparations required before primer in what remained of the day, chose this as a stopping point so I could finish some work on another project at the shop.  Next time, I’d finish up the pre-primer preparations on the hull.