Sounds like you are going to get familiar with fiberglass repair.... It really isn't that hard, just takes time and patience. I am currently using the
West System epoxy and it works great. The metering pumps makes getting the right ratio of hardener and
epoxy very simple. I am using the slow hardener and do one coat each night after work. I have a 12-18" crack between deck and hull at the rear crossbar of my H18 (complete seperate and could move the hull similar to you). It is where the hull comes up and meets the lip. I don't know the P16 to well, but presume it has the same old school 2 piece hull like a H16 and H18, where the deck was epoxied to the hull will a curled lip where the two connect.
What I do is run 2" wide cloth on the outside and then a combination of 2" and 4" cloth on the inside. I think I did a total of 5 layers on the outside and plan to do similar on the inside. Make sure you go a couple inches past the end of the crack. The first layer is the most important, make sure you sand the surface extremely well to make sure that first layer sticks. Then after each coat you need to sand and clean with laquer thinner. I feather out the layers of cloth to give it strength.
I also cut a hole to add a Viking port in the deck to allow access to the inside. Working through the openning is tough, but not many other options. One piece of advise is find a farm/ranch supply store and get cow obstetrics disposable gloves. They are shoulder length plastic gloves that helps keep
epoxy off your arm while working in the hull. I cut the finger tips off those gloves and then put my nitrile gloves over them so I still have decent touch, since that is all I have when sticking my arm in the port hole.
Also remember a resporator while sanding, don't want that stuff in your lungs. It sounds like a lot of work, but really isn't to bad, just time consuming. I have now done about 4 of these repairs on my H18M since it is a weak point, especially with the leverage of the wings.
Good luck.
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Scott, H18M in Chicago
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