When I bought the boat in February the front hatch was toast. Split completely in two.
I decided to just replace it, rather than affect a repair, even though plexi can be expensive. Professional Plastics has a warehouse near me so I just went there, although they are on the web as well. The shipping can be quite a bit for this sort of large and heavy item. The 30" x 30" x 0.5" square cost me $108 including tax.
I have a combination blade in my table saw, and I used it to cut the straight sides. Take it slow and it will cut nicely. In fact, I trimmed it again where the plastics company cut it off, as I liked my cut better than theirs. For the two angled cuts, I decided rather than to make a jig to use on the table saw, I would just take a small dovetail handsaw and cut them by hand.
Then using a little mouse sander and 220 grit paper, I smoothed and slightly beveled the sharp edges. I rounded the corners a bit as well, and then with the 220 sandpaper, frosted one side of the plastic so the hatch will let light through but it will not be see-through. You can see the paper backing in this picture showing through.
Here's my scrap test piece after trying the 'frosting' technique.
We used the old hatch to mark all the mounting holes in the new piece. The technique I used for the hinge holes which were way too close to the edge for my comfort as they were 1/4" I think, was to drill pilot holes increasing in size, and then as I got closer to the big diameter, I put the drill in reverse, and bored the holes with the bit going backwards so it would sort of melt its way through the plastic, rather than grab and split.
On the boat:
Stan
I decided to just replace it, rather than affect a repair, even though plexi can be expensive. Professional Plastics has a warehouse near me so I just went there, although they are on the web as well. The shipping can be quite a bit for this sort of large and heavy item. The 30" x 30" x 0.5" square cost me $108 including tax.
I have a combination blade in my table saw, and I used it to cut the straight sides. Take it slow and it will cut nicely. In fact, I trimmed it again where the plastics company cut it off, as I liked my cut better than theirs. For the two angled cuts, I decided rather than to make a jig to use on the table saw, I would just take a small dovetail handsaw and cut them by hand.
Then using a little mouse sander and 220 grit paper, I smoothed and slightly beveled the sharp edges. I rounded the corners a bit as well, and then with the 220 sandpaper, frosted one side of the plastic so the hatch will let light through but it will not be see-through. You can see the paper backing in this picture showing through.
Here's my scrap test piece after trying the 'frosting' technique.
We used the old hatch to mark all the mounting holes in the new piece. The technique I used for the hinge holes which were way too close to the edge for my comfort as they were 1/4" I think, was to drill pilot holes increasing in size, and then as I got closer to the big diameter, I put the drill in reverse, and bored the holes with the bit going backwards so it would sort of melt its way through the plastic, rather than grab and split.
On the boat:
Stan