With the new mahogany panel installed on the V-berth bulkhead, next I had to fit the side panels. I knew this was going to be a challenge, and I’ve been mulling over how to tackle it for a few years. The approach Chris Craft used involved 1/4″ medium density fiberboard, which (with enough screws) can be forced to contort into shapes that plywood doesn’t like to take. But I want to use mahogany rather than painted fiberboard, and of all the berths on a boat, the V-berth is the most ‘boaty’…I wanted the walls to follow the curves of the hull. But first, I needed to adjust the aluminum frames and the cleats that a clown of a woodworker installed a few years ago so the curves would be smooth.
The OE fiberboard panel
I saved this panel during the disassembly phase back in 2008 because I thought it would come in handy as a template. Recently though, I realized that fiberboard makes a great pattern for new panels made of the same material. But when using different materials with very different properties, it’s only useful in the roughest sense. More on that later.
Cleats installed by a former woodworker didn’t make smooth curves
The spray foam insulation and aluminum frame in the pic above obscures the mahogany cleats a bit, but if you can see the two pieces of wood don’t even come close to lining up. I’ll have to sand that down to make a smooth curve.
Completely meaningless cleat
I’m not sure what the woodworker was thinking putting that little mahogany cleat up above the porthole. I mean, I understand why it might be best to have a cleat there to support the plywood, but for that to happen the cleat has to be a very different shape so it aligns with the plane of the porthole surround plywood. A profile shot might make the point clearer.
See? Completely meaningless cleat! No way plywood could make that bend
On the bottom side of the round porthole opening, I’ve got some Chris Craft goofiness to deal with.
The mahogany cleat is proud of the plywood porthole surround, but so is the aluminum frame
There’s no way 1/4″ mahogany plywood will warp enough to seat on the plywood that surrounds the porthole opening, so I have to sand down the mahogany cleat and the aluminum frame here.
Finally, ready to test the fit the pattern
I attached a cleat to the new mahogany panel that tracks the shape of the closest frame cleats. But since the mahogany panel added thickness to the bulkhead, the original fiberboard panel needed some trimming to get it to fit again.
Close-enough fit at the top
Close enough at the bottom, too.
Fiberboard panel finally matches up to the round porthole opening
I need to trim a bit here
Next I took the fiberboard off and traced the outline on a sheet of cheap luan 1/4″ ply. It was looking pretty good until I tried to fit it up to the V-berth frames.
What fit well as fiberboard doesn’t fit well at all with plywood
Turns out plywood is a lot less flexible than fiberboard, especially when you try to make it bend in the X, Y, and Z axis all at the same time. No amount of clamps helped. When I tried to make the panel conform to the V-berth wall curves, I could only get two of the three axes to work at once. And that’s when it occurred to me that if there is a big difference between how fiberboard and cheap luan plywood behave, it was likely that the mahogany panels would also be different than the cheap luan.
I’m going to ponder a bit more on this before giving it a go. That mahogany plywood isn’t cheap, and I don’t want to end up with expensive scraps.
Next up in our 1969 Chris Craft Roamer 46 Refit: Cutting and Fitting the V-berth Port Side Mahogany Panel