[ Home Page ]    [ History ]    [ The Project ]

Project Log:  Friday, March 28, 2014

The day's main focus was to be the installation of the large acrylic panel to close off the overhead hatch in the pilothouse.  For this installation, I followed the instructions provided by Sika, the manufacturer of the adhesive sealant I chose to use for the installation.  I'd never used this particular product before, nor had I installed such a large panel in this way.

I began with basic preparations up on deck, where I masked off the decks around the opening, mainly to protect the nonskid from stray handprints or sealant.  With hindsight, I should have masked right off to the actual bonding surface around the hatch opening; this would have been useful in applying the Sika 209 primer later in the process, as it turned out.  As it was, I only masked this area much later in the process.

Masking complete, I lightly sanded the bonding surface, as directed, then cleaned it thoroughly with solvent.  Meanwhile, I masked off a 2" wide perimeter band on the bottom of the acrylic panel (the bonding surface), and lightly sanded the plastic, again as directed, before cleaning with solvent.  At this point, I started wearing nitrile gloves to prevent any skin contamination on the panel or the hatch bonding surface.  I also masked the smooth edge of the panel to protect it from sealant.

Next, I applied the Sika 209 primer to the bonding surfaces, on both the hatch and the boat.  This is where I realized that masking closer to the actual edge of the hatch bonding surface would have been helpful, but this surface was slightly elevated from the surrounding molding, and therefore, with care, I pressed on and applied the primer without making too much of a mess.  But it would have been better to mask it closer.  I used only a small amount of the primer container; the product would go bad soon so the rest would be wasted, but the primer is supposed to provide a tenacious bond between the acrylic and the 295-UV adhesive sealant.



The primer had to sit for 30 minutes, so while I waited for that I went ahead and installed a stainless clamshell fitting over the chain locker drain hole, securing it with machine screws in tapped holes, and sealant.


To avoid pressing all the adhesive sealant out of the bonding seam when the panel was installed (a certain thickness and elastic layer was required), the instructions called for temporary 3/16" spacers to be placed around the edges of the bonding area; I had ordered some nylon spacers that would do the job.  Because of the size and unwieldiness of the panel, I was concerned these spacers would move around while I installed the panel, so I used tiny dabs of hot glue to hold them in place right at the outer edge of the bonding area, leaving room behind for the actual adhesive sealant bead.  I placed three spacers on each side of the opening, or about 10-12" apart.  I didn't use any more than I thought necessary to hold the plastic in the proper position.


I cut a large upside down V-shape in the sealant tube, and applied a heavy bead of the stuff inside of the spacers.  The actual surface to which the plastic would be bonded was about 3/4" wide, a nice flat area outboard of the wooden trim within the opening.  So between the plastic spacers and the inside edge of the bonding strip, I had a nice 1/2" or wider area for the adhesive sealant bead.  I ensured the bead was taller than the spacers.  I used a full tube, plus a little more.


Next--and I could have used help here--I got the panel in place over the opening, and somehow managed to get it into position without making a mess or ruining the whole installation.  Good times.

I pressed the panel into the sealant bead, till it contacted the spacers, and left it alone to cure for a few hours, as directed.




Sometime later, after a few hours' cure time, I removed the nylon spacers, grabbing then with needle nose pliers and pulling them out of the gap.  Now I had to apply more of the sealant into the remaining gap.  With some experience with this particular adhesive sealant and its working properties now (evil, sticky, messy stuff), I chose to first mask off as close as possible to the bonding area, since I didn't want the sealant to go everywhere, and I'd found it was challenging to clean up.  So after masking, I used a caulking nozzle with a small opening and filled the seam with more of the adhesive sealant, then tooled it smooth with my finger before removing the masking tape for a (relatively) clean edge.





During the several hours in between stages of the hatch installation, and afterwards, I worked on other things, mainly the mast wiring junction.  During the bulk wiring stage of the project some time ago, I'd led various wires beneath the overhead to an exit in the passageway.  These wires included two lighting pairs (anchor light and steaming light (technically called a masthead light, though frequently not found at the masthead)), a VHF antenna cable, and a SimNet network cable for the masthead wind instruments.

I purchased a plastic junction box, and drilled a large hole in its top edge, which I installed up near the overhead (leaving enough room to remove the overhead panel as needed).  This little box had ample room within for the mast wiring connections needed, and would make breaking these connections when the mast was unstepped easy and convenient.

Into this box I installed a SimNet T-joiner, which would provide connection between the two sections of network cable required for the wind instruments, and a 6-position terminal block for the mast wiring connections, using only four of the terminals for now.  I also terminated the VHF cable with a splice connector so I could easily attach the mast end later.

Through the back of the box, I drilled a comfortable hole into the head, which was where I planned to install a fitting for the wires to come down from the mast and into the junction box.  The unfinished area of the overhead is where I had to remove some of the inner laminate long ago to gain access to the mast step bolts; after I reinstalled the mast step or tabernacle, I'd build a cover for this area.


To lead mast wires cleanly and easily through the deck from a deck-stepped spar, I like to use a nice stainless steel through hull fitting, installed upside down (with the barb on deck).  Then I run the mast wires from a fitting at the mast and through a length of hose and through the fitting into the boat, providing a waterproof, attractive, and worry-free conduit.

After a few measurements inside and out, I drilled a pilothole from inside to locate the fitting, then drilled a 1-7/8" hole from above.  In the usual way, I reamed out the core from within the opening, and filled the void with thickened epoxy to seal the core at the penetration.


I started an attempt to install a fill line for the forward water tank, but with the tight access and very stiff and cold hose that I'd just brought in from cold storage, I was unable to connect the hose at the tank, so I left that for another time.

Total Time Today:  6.5 hours

< Previous | Next >

The Motorsailer Project
Site design and content ©2010-2015 by Timothy C. Lackey.  All rights reserved.

Please notify me of broken or missing links or other site issues.
You can always find every day's project log links on The Project page.

Questions and comments | Home Page
V1.0 went live on 8/26/10