Replaced Glass Windows with Acrylic

[Seahorse24]

I replaced eight glass windows that go on our Yankee Seahorse with Acrylic. The total costs was sixty dollars for the 2 foot by four foot sheet of Acrylic. The original boat windows could not be cleaned because they were two separate pieces of glass sandwiched together and they had fogged internally.

The hardest part of this project was cleaning off the old chalking around the aluminum frames. The stuff had hardened over time and was difficult to remove. We ended up letting the eight window frames soak for a couple of weeks in soapy water to soften the old chalking up so it would come off.

We placed the old glass windows on the 2' by 4' sheet of Acrylic and traced the outlines with a pencil onto the brown paper covering the sheet of Acrylic. We then used a jigsaw to cut around the outlines. Medium speed on the jigsaw using a metal blade worked best. The Acrylic was easy to cut. We then lightly sanded the edges before inserting the Acrylic into the rubber gaskets that fit into the aluminum frame guides.

My question:

Should I use 100% Silicone Clear Chalk when I insert the aluminum frames back into the window slots on the boat? I know Silicone chalk remains flexible and works well for sealing house windows, but will it work well for boat windows? One of the old windows had developed a small leak and we hope to be able to seal all of the replacements well enough so they do not leak in the future. Thank you for your help.

I have attached a few photos. The brown stuff behind the window frame slot is cardboard we used to keep the sanding dust out of the interior cabin.

 

[TENACITY CS36T]

Why not use a proven Butyl like the stuff Maine Sail sells on his site, I've used this as well as many others and can attest to its valuable properties for more than just rebidding hardware etc....check his site a compass marine how too's.

 

[caguy]

Everyone is going to tell you Dow795 but I like butyl taper for sealing the frames. It is cleaner and easier.

 

[woodster]

if you are bonding the acrylic to some thing.... then use Dow 795 it is silicon based and works well but if you are bedding the frames to the hull the butyl tape is as good as it gets

they both have there places and applied properly do a fantastic job

 

[Seahorse24]

if you are bonding the acrylic to some thing.... then use Dow 795 it is silicon based and works well but if you are bedding the frames to the hull the butyl tape is as good as it gets

they both have there places and applied properly do a fantastic job

Thanks,Woodster. I am not bonding the Acrylic. It is already sealed inside the aluminum window housings with rubber gaskets. The Aluminum frames fit into the cutouts in the fiberglass and are held in place with an inner frame that squeezes the two Aluminum frames against the fiberglass walls on the upper cabin area. screws hold these two pieces together. A quarter inch of chalking goes around the inner part of the Aluminum frame that goes right around the edge of the cutout.

I will check out the butyl tape you mentioned. I appreciate all of the responses to my question.

 

[Scott T-Bird]

Yes, check into the butyl tape. Many despise silicone caulk adhered to the fiberglass walls because it is so difficult to remove when the job needs to be done again. Nice looking improvement!

 

[Seahorse24]

I have been doing research on the Butyl tape. It appears to be exactly what I need. It will be easier to work with than silicone chalk, and it remains flexible for many years. If I have to repair a window in the future, it will be easy to remove.

 

[Brian S]

Here is Maine Sail's article on how to bed with butyl tape. http://www.pbase.com/mainecruising/rebedding_hardware A link to purchase from his is at the end. His is formulated just for marine bedding, other forms of butyl tape are not, and are unsatisfactory.