[C320-list] Portlight/hatch update

[Michael Leschisin]

Hey David,

I Just did mine last weekend.  It wasn’t too bad just kind of time consuming.  

Start by taking out the hatch trim piece on the inside of the V-berth.  I used a small putty knife to gently pry the caps off of the screws that hold the "screen clips” and a couple of mounting screws into the white plastic trim piece inside the berth, then remove all the screws and clips.
Then you should then be able to begin to wiggle out the trim which goes up and mates, with the hatch flange in the deck hole.  Mine was a bit tricky to get out since some of the butyl tape use to previously bed the hatch had oozed onto the trim and was hold it in place.   It took some gentle coxing to maneuver it out without cracking the trim, but it came out slowly.  

Once the trim was out, I simply removed the screws holding the hatch to the deck. (You’ll see them once you open the hatch.) I then used a somewhat dull putty knife (so as not to dig into the gel coat) to slowly break the old seal between the hatch and the deck. I did what I could going round and round by hand until the knife was behind the lip of the hatch enough so that if I did gouge the gel coat it would be hidden by the newly bedded hatch.  At this point I used a small tack hammer to slowly tap my way around the hatch and fully break the seal.  I tried to do each position a millimeter or two at a time rather than trying to drive the knife all the way in, all at once.  When I had the knife about halfway in, I began giving it a gentle twist in each position to help break the seal.  At this point I also started tapping some wooden wedges under the lip (I carved down some cloths pins for this) spacing them evenly so as not to twist or bend the hatch and lifting only a millimeter or two at a time.   Once I broke the seal, the hatch lifted out fairly easily.  I was able to confirm that the seal was leaking rather than the lens since a good chunk of the old sealant was covered in black mildew.  Obviously water was getting in behind it. 

I used a plastic razorblades scraper to remove the old butyl sealant from the deck and from the underside of the hatch and then used paint thinner to get the last bits that wouldn’t come up.  I’m not sure if paint thiner is an issue on polycarbonate windows but I was super carful not to find out the hard way that it was.  Once I gave both hatch and deck a good paint thinner wipe down, I cleaned them up with denatured alcohol.  I was surprised that the hatch was screw directly into the deck core rather than through bolted and most of the holes were elongated from mounting the old hatch.  I decided to drill them out wider, fill them with West System epoxy and then re-drill for mounting.  This added another day to my project since I had to wait for the epoxy to cure, but I felt a lot better about water not seeping into the deck. 

I used Butyl tape from Sail Rite to reseal and with the hatch in the closed position, flipped it over and on a towel, and worked the butyl tape into position around the underside of the lip.  I was careful to leave a gap on the inside edge for the trim to fit and I did two layers of the tape.  In retrospect I think that was too much.  If I could do it again, I’d probably lay one layer of the tape flat along the lip and then roll out a strip of Butyl that’s half its normal volume and lay that over the flat strip.  

If anyone from the group has any experience on the proper amount of tape to use, that would be helpful.  I figured more would certainly cover everything for a good seal, but I had quite a bit of clean up to do as the extra Butyl seeped from under the hatch.  

I lightly laid the hatch back in the deck hole, and before opening it went down below to put the trim piece back in place.  The hole in the deck is a few millimeters wider than the hatch on all sides so I had to use a small screwdriver to shift the hatch around and find a position where the trim would align and slide back into place.  I positioned the trim slightly up the hatch flange, then opened the hatch to check the alignment of the screw holes.  Poking through the butyl I was able to find the holes in the hatch lined up well with those in the deck, so I slid the trim all the way up and used a couple of screw (and the screen tabs) to hold it in place.  I wrapped each of the deck screws with a collar of butyl for a seal under the screw head and used a cordless drill with the clutch set to about 30% to seated all of the hatch screws.  I alternated front, back, side to side, so the hatch would bed down evenly.  I increased the drill clutch to about 50% and since I’m in a cold climate, used a hair dryer to warm the aluminum rim of the hatch base.  I warmed it, tightened it down and waited a half hour or so, then repeated warming and tightening a time or two. As the Butyl squeezed out the edge, I cut it loose with the the plastic razorblades.  I got the hatch to a point where it had all but a couple of millimeters to go and it was getting quite tight, so knowing I had a good seal (since butyl had seeped out of all sides) I decided to let it sit for the week.  I’ll come back to it this weekend, tighten it up by hand and slowly continue to do so this summer until I see the aluminum lip flush with the deck.  I didn’t get all my screws and screen tabs back in place on the inside before having to leave, but I’ll finish all that up this weekend.

Hope this helps,

Michael Leschisin


Wild Blue Yonder
#995
Menominee, MI


> On May 3, 2022, at 9:40 AM, David Wellerstein <dwellers at mac.com> wrote:
> 
> So, four new portlights installed and inside trim pieces trimmed and in place.  Thank goodness for the Dremel with a cutting blade.  It wasn’t pretty but it worked!  That was quite literally the hardest part of the job!
> 
> Now it’s on to the Bomar trapezoidal hatch up front.  It seems to be leaking from the aft-most corners of the hatch.  I’ve put new fasteners in the empty holes but I think I need to remove and re-bed the whole hatch.  If anyone has done that, I’d love some tips.  Do I need to remove the lens or can I just remove the whole unit like a portlight?  I don’t think the dog o-ring replacement is necessary.  
> 
> The replacement hatch from Catalina Direct is over $1000 so I’ll try to keep the current one if possible.
> 
> Thanks!
> 
> David
> “Dream Catcher” #118
>