Be careful ...
As has been already stated in this thread the OP is installing ACRYLIC (Acrylite GP) ports and most polyurethane & polysulfide bedding compounds are contraindicated with acrylics.
A structural commercial grade silicone like Dow Cornings 795 or perhaps 995 would be an alternative choice as they will not interact with the acrylic and damage it like a polyurethane or polysulfide could depending on the product. Sikaflex 295UV (polyurethane) is specifically engineered for acrylics and polycarbonates. Dow 795 & 995 are NOT Home Depot off the shelf silicones.
These structural glazing products glaze large plate glass windows in sky scrapers in high winds, with lots of panel flexing, for years and years and these glass panels weigh a LOT! . Even if you had aluminum, bronze or stainless ports I'd use 3M 101 or 3M 4200 MAX but, preferably a marine suitable butyl tape.
Even 4200 is far to adhesive & not really necessary for bedding aluminum mechanically fastened ports but it's still a 100% better choice than "Death Grip/Satans Glue" or "5200". 4200 has 50% of the strength of 5200 and trust me it's still a LOT of strength.
Having bean around boats since 1971, & my family for decades before that, I can assure you that NOTHING on a boat is permanent not even a keel. Everything on a boat will eventually leak and with 5200 it's good luck getting it apart when you need to do the repair in the future!
Trust me I'm the biggest anti-silicone, and anti-5200, for that matter, person on the planet when it comes to boats. However, for certain jobs, a specialty, structural silicone may sometimes the best product for the job and traditional polyurethanes and polysulfides may not always be the best choice. 5200 is not even allowed on my boat, for any reason, as it's death grip adhesive properties are 1000% unnecessary IMHO even for a keel joint and yes I've had to re-set a keel originally done with 5200 that was leaking...
Silicones are terrible but sometimes you just don't have a choice like when trying to bed certain plastics. If it were me I'd call Cyro Plastics 1-800-631-5384, the maker of Acrylite GP. Acrylite GP is a beefed up cast acrylic sheet and may be more resistant to polyurethanes and polysulfides, but I'd check first. You know measure twice, cut once....
If you do use a silicone like Dow 795 tape off all areas around the port so you don't get ANY on the gel coat other than where you want it...
As has been already stated in this thread the OP is installing ACRYLIC (Acrylite GP) ports and most polyurethane & polysulfide bedding compounds are contraindicated with acrylics.
A structural commercial grade silicone like Dow Cornings 795 or perhaps 995 would be an alternative choice as they will not interact with the acrylic and damage it like a polyurethane or polysulfide could depending on the product. Sikaflex 295UV (polyurethane) is specifically engineered for acrylics and polycarbonates. Dow 795 & 995 are NOT Home Depot off the shelf silicones.
These structural glazing products glaze large plate glass windows in sky scrapers in high winds, with lots of panel flexing, for years and years and these glass panels weigh a LOT! . Even if you had aluminum, bronze or stainless ports I'd use 3M 101 or 3M 4200 MAX but, preferably a marine suitable butyl tape.
Even 4200 is far to adhesive & not really necessary for bedding aluminum mechanically fastened ports but it's still a 100% better choice than "Death Grip/Satans Glue" or "5200". 4200 has 50% of the strength of 5200 and trust me it's still a LOT of strength.
Having bean around boats since 1971, & my family for decades before that, I can assure you that NOTHING on a boat is permanent not even a keel. Everything on a boat will eventually leak and with 5200 it's good luck getting it apart when you need to do the repair in the future!
Trust me I'm the biggest anti-silicone, and anti-5200, for that matter, person on the planet when it comes to boats. However, for certain jobs, a specialty, structural silicone may sometimes the best product for the job and traditional polyurethanes and polysulfides may not always be the best choice. 5200 is not even allowed on my boat, for any reason, as it's death grip adhesive properties are 1000% unnecessary IMHO even for a keel joint and yes I've had to re-set a keel originally done with 5200 that was leaking...
Silicones are terrible but sometimes you just don't have a choice like when trying to bed certain plastics. If it were me I'd call Cyro Plastics 1-800-631-5384, the maker of Acrylite GP. Acrylite GP is a beefed up cast acrylic sheet and may be more resistant to polyurethanes and polysulfides, but I'd check first. You know measure twice, cut once....
If you do use a silicone like Dow 795 tape off all areas around the port so you don't get ANY on the gel coat other than where you want it...