Cabin ventilation
Jim,I installed two operable portlights in the cabin area of my 272 several years ago. I located one of them directly above the galley in the fixed portlight and the other in the opposite portlight to port. They have served me well for the past few years. No problems with leaks. (Knock wood...I mean fibreglass:>)I found a couple of suitable portlights at a marine flea market at the Cleveland boat show. They are eliptical in shape, but any shape will work as long as they will fit into the area in the existing portlight which must be cut out to receive them.Here's how I did it.First, I selected the location to be cut out and then masked off the entire area with masking tape inside and out. This was intended to give me a surface to trace out the opening for the lights and also to prevent splitting of the plexiglass. After laying out the hole locatins, I drilled holes at the corners to prevent stress cracks while sawing and using a sabresaw (jigsaw to some folks) I cut out the openings from the outside.After checking for fit and drilling holes for the mounting nuts and bolts, I bedded the new lights in marine silicone, let them set for awhile to allow the sealant to set up, then bolted everything into place.Problems. You must be careful when cutting the plexiglass. The plexiglass cracked in one place in spite of my precautions. I attribute that to the age and brittleness of the plexiglass. My boat is a 1986 model. Although there are no leaks and the crack is difficult to see, it is there and may become worse over time due to further aging of the material and the normal flexing of the hull and cabintop from sailing.TomNote to Frank and Bob. Hope you guys are contiuing to have a great sailing season!!!