Adding an opening portlight to fixed glass?

[haveaday]

My carver voyager 570 is woefully defficient in ventilation. The pilot house has an opening door on the starboard side and a large fixed light on port. I'm wondering what the feasibility would be of cutting into the existing window and adding a sliding window assembly inside of it. I realize this is likely to be difficult as the existing window is tempered glass. Unfortunately with the style of the existing windows I don't think a sliding unit to replace the entirety of the fixed window.

Has anyone done something like this?

Thanks
Ben

[Boulter]

If I am not mistaken, tempered glass can only be worked before tempering. So to pursue your idea would likely mean removing the existing glass and replacing it with a plastic material as your starting point.

Boulter

[haveaday]

Originally Posted by Boulter

If I am not mistaken, tempered glass can only be worked before tempering. So to pursue your idea would likely mean removing the existing glass and replacing it with a plastic material as your starting point.

Boulter

That's what I feared. Thanks