1969 Chris Craft Roamer 46 Refit: The Starboard Salon Bilge Vent Duct

I keep hearing from the mobile paint and fiberglass repair guy that the estimate for repairs for the big Nor’easter damage is almost done. But…alas…I’ve still not received it. So I continue working on weatherproofing the bilge and engine room vents on the starboard side of the salon.

Chris Craft’s approach to bilge vents

What we have here is two 3/4″ solid mahogany boards on either side, with 1/8″ fiberboard for the face and back. I don’t know where this one came from, but I removed it a decade ago  because it was failing when we began this project. For some reason, Chris Craft put a piece of 3/4″ plywood over the top of part of the fiberboard on this particular bilge vent. It’s all sealed up with what looks like grey primer and held together with rubbery sealant and some bronze staples. I’m sure it worked fine for ten years or so, but it’s got its problems.

Fiberboard really stuck in some spots

When I pulled the fiberboard off the mahogany, you can tell the rubbery sealant really stuck on the spots where it left some fiberboard behind. But you can also see where the rubbery sealant didn’t stick to the mahogany at all.

Bronze staples are still holding fast 50 years later

The side of the fiberboard that faced the weather

Again, you can see where the sealant really stuck, and where it didn’t stick at all.

Now let’s look at that starboard salon forward bilge vent

I left the forward vent duct in place because it looked like it was in serviceable shape. Turns out it wasn’t in quite as good shape as I first thought.

Moldy white paint on the outside

But up at the top, just behind the longitudinal deck frame, you can see daylight through the pressboard

I’m glad I took off the face panel

Lots of gaps at the top

So, in addition to the hole in the salon-facing pressboard face panel, you can see that the back panel isn’t even touching the mahogany side board. The gray primer/sealant is also gone from the mahogany in spots. And at the toe rail, the rubber sealant is only there for appearance’s sake, apparently. There’s no actual contact between the rubber sealant and the pressboard.

I considered removing the duct and rebuilding it, but the mahogany sides are very firmly attached to the underside of the deck. So I decided to fiberglass what’s there instead.

First, rough up the surface and remove anything that isn’t well adhered

I also confirmed that I can use sticks up against the hull to press the back panel into full contact with the mahogany sides.

Ready for epoxy and fiberglass

Wetted out glass cloth and epoxy thickened with cabosil

I spread a bunch of epoxy out on a piece of scrap shrink wrap plastic, then laid on a sheet of lightweight fiberglass cloth to soak it up. While the ‘glass was still soaking, I wetted out the duct with epoxy

Epoxy thickened with fumed silica to the consistency of whipped cream

Thickened epoxy fills every gap and corner

Longtime readers will know what came next, after I jammed sticks in to force the back panel into contact with the side panels.

Fillets!

I do love my fillets. They look nice and also give a radius to the corners, which makes it easier for the fiberglass cloth to have full contact, and water won’t find any nooks or crannies to hang out in and cause havoc.

Next, I laid on the fiberglass cloth

Next day, the epoxy is cured

The duct needs a face panel

I’m using 1/4″ Douglas fir marine plywood for all of the duct face panels I’m making. I cover them with a layer of fiberglass on the weather-facing side to ensure they’re watertight.

I need to install an insulated panel to the left of the duct, too

Framing out the backing cleats

Next day, the epoxy on the panels is cured

Excess fiberglass trimmed off nicely

Duct panel marked off for screw holes

Countersunk screw holes every 6″

The insulated panel needed a bit of trimming to fit

 

Just about ready for installation

Dry fit is done

These panels are behind the electric panel, so I’m not terribly concerned about appearance.

Next up in our 1969 Chris Craft Roamer 46 Refit: Installing the Starboard Salon Bilge Vent Duct