Building a transom deck hatch on my Frisco Flyer?

[WayneS]

My 1964 Frisco Flyer (fiberglass hull, teak cabin and deck, deck fairly new) has a fairly long transom deck, and I would like to build a small hatch on the port side for access and storage.

The teak (actually Iroko) deck is reinforced by:

1.  A king plank about eight inches wide, running from cockpit to transom;
2.  Deck frames
3.  Deck shelf on the quarters.

(There's also a deck clamp, but that is irrelevant for this project.)

I can build a hatch frame which would attach on one side to the king plank, and on two others to deck frames.   These supports would require (and I would make) no alterations to frames etc.  But the deck shelf is too far to one side to use to support the hatch frame, and the shelf is the wrong shape (curved) anyway.

I don't like the thought of installing a hatch frame which would not be supported on all four sides.  Neither do I know a good, solid way of installing a support member to support this side.

Anybody got any ideas?  All assistance appreciated.

Thanks--

[AdriftAtSea]

A photo of the area would help. 

I would suggest you put in a small beam to support the fourth side of the hatch. It could be attached to the two deck frames that you are using to support two of the sides of the hatch. You could glass in the beam, to help protect it from water exposure and help strengthen the area as well.

[Parrothead]

Laminate the last side in place maybe?

[ntica]

I put this here... Been thinking, after some advice from you etc. to install a hatch on my foredeck. A question, when taking/saw up a hole, will not this increase the trength, and worse maby bend the foredeck out of shape???