Hi Larry!
The flush hatches secured by magnets seems to be a hot topic. I've briefed some of the other responses, and the bungie straps inside the bulkhead is a good idea for me, as the boat I installed them in is touring single, not really suited to carry too much gear. I figured my love would be riding with the hatch only half or less than half full of gear, most of the time, and thought some kind of method of securing loose gear was in order. I remember seeing a method of securing hatch covers "internally" by a system of bungie cord secured to the inside hull surface of the bulkhead, so that the line ran at an angle to the hatch lid, such that the line did not interefere with storage space as much. The line was secured by pvc pipe that had been cut in half lengthwise, and then cut into short pieces. These pieces were then epoxied to the hull and glassed over. I don't remember their set up exactly, but I did it in my wife's boat to secure the "webbing of bungie cord" as described by one of the other respondants in this thread (sorry to not get your name right away, but I can't seem to go "back" right now to look up the info). I tied off some thin parachute cord to the pvc half pipe pieces to secure the bungie cord. You might be able to do the same for your boat, but put a pvc half pipe on the inside surface of hatch. I think I saw this on the Newfound Woodworks' website (www.newfound.com), but it was a while ago. They're friendly folks and if you e-mailed them, I'm sure they would respond soon. I saw the magnets in use on Rob Macs' "Shooting Star", and he describes installation in his instructions for the boats he designs. He'd be sure to get back to you with any questions. Rob Macs' company is named Laughing Loon, and the web address is www. Laughingloon.com.
Another of the respondants (Sorry I can't identify you by name, but I can't figure out the bulletin board thing without loosing the stuff I've written here) mentioned the strength required to pry open their hatches attributing that to the stregth of the magnets, but I wonder if it was air preasure that made it difficult to open up the hatch. Thanks for including me in your discussion, Sincerely,
Bill

: Bill,

: Most of the wate this boat sees is inland water, the Ca Delta and such. i
: carry a compass in my pfd, but do not have a deck mount. I have checked
: out the 3/8 magnets and the compass doesn't seem to be affected after
: about 10 in away from the magnets. I placed the forward hatch so that i
: have 3 in from the bulkhead (my feet) to the aft edge of the hatch. That
: puts the compass 12.5 in from the hatch should I mount it in the deck.
: Right now there is no need for a semi-permanent mount.

: I am concerned about something banging the hatch loose when inverted. I'm
: going to check and see what forces are required to push the hatch off from
: the inside soon. If all else fails, I'll run a permiter line and use that
: as an excuse to put a strap or two across each hatch.

: larry.