When placing the hatch slam latch to check the fit and clearance I am not sure if I can make the fit precise enough to have it close securely. I've seen it in many other builds in this forum and will continue to ponder it.
I had first thought of having it catch along the side walls (they do have a stiff metal frame after all) but there is the ~1/4" gap along side the hatch and the throw of the catch is not huge so I thought about a longer throw bolt latch. I discovered that the T handles I have with their square shaft will also fit a garage door latch and they are pretty cheap. I found them for $8 at the big orange box store and removed the extra latch in it so it won't lock on its own, and filpped the bolt around so one would fit on each side of the hatch.
I saw a nice tall metal catch in the build journal of the
Alaskan Benroy that I may still consider once I get to the point of checking my hatch's fit as I get it all installed and trimmed.
Before I worry about the hatch latches, however, I have some more hatch issues to resolve.
With the slight crown to the shape of the floor, I need to shape the bottom edge of the hatch and used a block plane to shape the poplar frame.
With some elbow grease I got it really close and the rest can be pulled in by pressing a knee against the outside edge when latching it if needed.
Note there is NO clearance between the hatch and the floor so either I need to remove a small length of the hatch arc or allow the hatch to sit slightly high, which may then affect the ability to seal along the side wall or need a taller rubber seal. Unfortunately, an "opportunity" to remove a fraction of an inch from the length of the arc of the hatch has come along to fix another issue.......
I have realized that I cut my hurricane hinge too short on the moving hatch side of the hinge as I didn't leave an overhang to lay down on the side wall seal.
This was after installed the upper portion of the hinge permanently with rivets and sealant (I had been holding it in place with clecos til the day before I realized this).
And after installing the aluminum skin and carefully shaping and sanding a shim to close the gap I described a couple entries ago....
I looked into arranging the side trim to compensate but I could see a potential for binding it in the hinge and certainly for water to sneak by. I even mocked up a few configurations with scrap pieces I had but I figured the water droplets just won't care how hard I work or how much time I spend, they will still get through. I looked through the forum and found that other have made this same mistake and ended up getting a new hinge. I called Frank Bear and discussed my ideas and decided to get another hinge that should be here soon.
I removed the hinge from the hatch and ended up having to cut holes in the blocking to get to the back side of the carriage bolts I used to attach it so thoughtfully (so much for that idea!). With the top ledger board of the hatch frame exposed again I'll plan to carefully slice off a small fraction of an inch to shorten the arc of the overall frame to recover some of the gap I was missing at the bottom.
Finally, I ran into one more issue but it is more manageable. I had glued the aluminum hatch skin on the luan surface with contact cement as done by some others before me - I figured that since some folks float the skin that the cement would help for while but if it eventually fails all the trim and hardware installed eventually will hold it in place. I had left it clamped for about 4 days but when setting it up to remove the hinge bolts I saw it slowly coming loose. For now I have just re-clamped it and will get the trim all in place once the new hinge arrives. I'll have the hinge on the top, T molding on the sides and a wide band of tread plate across the bottom, plus tail lights, license plate light and hatch handles.