: I should have remembered that.... good thread, and excellent 'explainin'
: photos, btw. Thanks.

: Ric - It's monday, and I haven't had my fair share of caffeine - since the
: cutouts are more or less oval (at least in my plans) how do you align the
: pattern, externally, with those four holes and the work you've done
: internally? I can see me getting this part messed up.

Sorry, I left some details out.
Step 1: tape the pattern to the deck and draw the outline on the outside of the deck. Choose 4 spots to mark the position for the holes eg. front and back of the hatch on the midline and outside edges or near the "corners" such as they are. Mark these spots on the pattern and the deck. (Just to be clear, the holes are on the rim of the hatch, what will be later be the saw cut.)
Step 2: drill the holes from the outside.
Step 3: remove the pattern from the deck and turn the deck over, locate the four holes on the inside and line them up with the 4 marks you put on the
pattern. Tape the pattern in place and draw the hatch outline again, this time on the inside.
Step 4: put plastic film or some kind of mold release in place and make the lip, aligning it on the outline you drew.
Step 5: take out the lip after it has cured and cut the hatch from the outline you drew on the out side.

I hope this helps, I don't think you can mess it up. It is important though to try to get the holes square to the surface of the deck ie. you don't want them on any kind of slant.

Ric