Mk-1 bulkheads under settee and couch, forward of tanks, are they structural?

[Noah]

I am in process mapping out install of my  tank monitor system which requires foil strips on be attached to holding tank and starboard water tank. As many of you know the tanks are jammed in there tight. There is a thin plywood glassed-in bulkhead (aft end) with a bunch of stuff; macerator pump, hoses, etc. crowding the area on the aft side of the holding tank, and the icebox is tight on the water tank side. The inboard sides of both tanks are flush up against the settee fiberglass. The forward ends of the tanks are buried and not reachable from the locker openings. However, they could be reached from the next compartment forward, if I cut and installed a Beckson-style inspection port in the compartment's aft bulkheads. The bulkheads are about 3/4 in thick. Any reason why I should NOT cut through these and install 4 or 6- inch ports to be able to reach in and install sensors onto. the forward faces of the tanks?

[Stu Jackson]

Noah, they both appear to more more "fore&aft" supports than structural members.  Consider just using a sawzall or a jigsaw with a short blade to cut slots wide enough to give you access for the strips on the tanks.

[Jon W]

Hi Noah,
       When I had bulkhead questions I called Catalina Yachts in Florida and spoke to Warren Pandy. I think the phone number I used was 727-544-6681.   Jon W

[tgsail1]

We recently had the same discussion in the C380 group. My C380 has one such "bulkhead" next to the holding tank. It was in a bad spot for access. When I asked the group how they dealt with it, most said they had no such structure. That let to a call to Warren Pandy who suggested that the bulkheads like those, while not purely structural could have been added in production as an option for the person installing the tanks- maybe easier to glass in a piece of plywood than manufacture a supporting bracket. That said, he did not go as far as to say remove it, but suggested cutting away portions of it as needed to get the job done. This is 100% consistent with Stu's suggestion.

[Ron Hill]

Noah : I agree with Stu that it is a "partition" and not a bulkhead.

However, I'd use a 4" hole cutter rather than a jig saw or saber saw.

A thought

[Noah]

Thx folks. My thougts too. I will take a 4-1/2 in. hole saw to the holding tank side bulkhead (if the hole saw's mandrel  pilot drill bit isn't too long). I don't want to puncture the holding tank!!!  I believe I might be able to install the water tank foil strps and sensors by reaching down with a pusher stick as someone else discribed. That side has a bit more "visable" room.