36 ET Aft Hard Top Load

[marko]

Hey ET'ers, phone home!
Working on installing a boom and light rigging (to brace existing mast) to be able to lift a light weight dinghy onto the aft roof, without the motor. There's a motor mount on the transom, which the boom could also help handle the outboard: from dock to engine mount to dinghy in the water. I've seen some 36 ET's with a RIB & motor on the roof and it seemed fine. My target is 200 to 300 lbs, plus one person. Have had the Zodiac up there, which is under 100 lbs. plus two guys (not big).

Anyone know what the roof composition is? I assume it's a foam core, but what type? I've heard that the hull core is Divinycell, maybe it's the same? Any plywood? Any aluminum framing? Don't want too much weight up there not just for structural reasons, but also stability, so what's worked in the past? Also, I'm getting water into roof core around sliding hatch, weeps back out along bottom (underside) fiberglass seam which has separated and stains ceiling. Don't want to repair and seal in water, maybe need to take apart and re-seal sliding tracks? Comments?
Thanks, Mark
At Last

[marko]

Partial answers: water in roof panel
As part of my boom project, I was working on new tie downs for the synthetic trim caps on top of the roof which are above the roof supports. I found both trim pieces loose and all old sealant worthless when the trim was removed. There were only two screws holding each one down and found water coming up out of trim screw holes from inside the roof. I went below and drilled weep holes outboard of roof supports and water poured out, see photo. I also removed the ceiling lights and found water in one of them and found foam could be felt inside wire hole. So, the partial composition of roof is a foam sandwich panel as suspected, but probably not honeycombed since water seems to migrate readily within. Any aluminum, fiberglass or wood reinforcing is still unknown, but you'd think there'd be something at least side to side at the roof supports perpendicular to the fiberglass ribs on top. The bolts down to the roof supports looked fine and still well sealed (maybe 5200?). So I cleaned the trim and roof, resealed with 4000 UV and added a third screw to each trim. Water was still dripping out the weep holes the next day. The sliding hatch rails are next up to remove and re-seal, maybe some additional weep holes aft.

[DougSea]

Well, it's good to hear you're getting it (the water) out of there. If there's no wood then it's not a huge concern, although a northern boat, which experiences a hard freeze, certainly could suffer some damage from what looks like a fairly large amount of water draining out off there!

Keep us apprised of your progress!