DaveH6
Fixed window installed
I guessed right on the tint I selected when purchasing the 1/4" acrylic for the pilothouse windows. The pane is held in place with 12 #6 screws and is set in butyl tape.
When drilling screw holes in the acrylic I was concerned about cracking the material. I congratulate myself for no cracks and all seems well.
But... on the Woodenboat forum, a boat builder reported that after a couple of years his boat's 2x2' acrylic 1/4" thick windows developed cracks around the panel edges. These windows were set in VHB tape thus no mechanical fasteners. The boat owner lives in Alaska so temperature extremes might be a factor in his problems with acrylic.
Todd Bradshaw posts on the Woodenboat forum and is super knowledgable on a wide variety of boat issues and is one of a few individuals I accept advice from without question. He says that when acrylic is cut, ground etc. , stresses are introduced into the material which later cause problems such as cracking. To minimize this, the material needs to be annealed after it has been worked. This requires putting it into an oven at 200 degrees for one hour and then left until it has cooled.
I don't have an oven that big so no annealing for me.
I may learn that use of acrylic (especially for my attached fixed windows) is an expendable product situation with occasional replacement a reality.
I used a 40 tooth blade in my circular saw and had zero chipping problems and for the curves I used a metal cutting blade in my jig saw and experiened very minor chipping. On U-Tube a guy competes a metal cutting jig saw blade against an expensive blade made for cutting acrylic and found no discernible difference in the cut edge.
Fixed window installed
I guessed right on the tint I selected when purchasing the 1/4" acrylic for the pilothouse windows. The pane is held in place with 12 #6 screws and is set in butyl tape.
When drilling screw holes in the acrylic I was concerned about cracking the material. I congratulate myself for no cracks and all seems well.
But... on the Woodenboat forum, a boat builder reported that after a couple of years his boat's 2x2' acrylic 1/4" thick windows developed cracks around the panel edges. These windows were set in VHB tape thus no mechanical fasteners. The boat owner lives in Alaska so temperature extremes might be a factor in his problems with acrylic.
Todd Bradshaw posts on the Woodenboat forum and is super knowledgable on a wide variety of boat issues and is one of a few individuals I accept advice from without question. He says that when acrylic is cut, ground etc. , stresses are introduced into the material which later cause problems such as cracking. To minimize this, the material needs to be annealed after it has been worked. This requires putting it into an oven at 200 degrees for one hour and then left until it has cooled.
I don't have an oven that big so no annealing for me.
I may learn that use of acrylic (especially for my attached fixed windows) is an expendable product situation with occasional replacement a reality.
I used a 40 tooth blade in my circular saw and had zero chipping problems and for the curves I used a metal cutting blade in my jig saw and experiened very minor chipping. On U-Tube a guy competes a metal cutting jig saw blade against an expensive blade made for cutting acrylic and found no discernible difference in the cut edge.