12 December 2017

Baffling Dorades

Today was spent replacing the transmission control cable -- a fiddly job if there ever was one, and a job that required more contortionist skills than I imagined I had, to reach the nearly inaccessible shift lever mechanism. Helena and I got it done, but the job wasn't nearly as interesting as some of the other jobs we've done in the last few months...

I think I've casually mentioned working on our 'Dorade' vents several times. My first goal was to varnish the teak boxes, which had begun to suffer from exposure to the elements. Yes, teak is pretty resilient stuff, but if you abuse it badly enough, even teak will begin to rot. My boxes weren't that far gone, but they had certainly started strolling down that path.

Dorade boxes on the road to recovery
The solution? That lovely stuff called varnish. Not only does it look good, it's good for your wood. What is not to like?

I started by giving the boxes a light sanding, inside and out. This removed all the grey wood (just a thin layer on any piece of teak), and whatever finish (if any) that remained on the surface. In the photo above you can see an unsanded box in the foreground, and three in the background that have already had some TLC.

Then I started varnishing. This is usually a week-long process, because it's typical to have to wait 24 hours for a coat of varnish to dry. I'm sure this is why most people hate to varnish, and if this has been stopping you, I have the perfect solution: Alwgrip Awlspar varnish. You can re-coat after 3 hours, with no sanding between coats. If you stick to it, you can have your 6 or 7 coats of varnish done in a couple of days. Amazing stuff! It doesn't seem to have any UV protection, so I used a UV protected varnish for the last coat.

The results were great, but as I was slathering varnish, I realized that my Dorade vents weren't Dorade vents at all. They were just vents.

"Ah-ha!" I thought. "Maybe that's why they leak."

Yes, Helena had complained several times about the Dorade vent over her bunk leaking.

"Nonsense!" I'd said. "That's the whole point of Dorade vents! They don't leak."

"Then these drips must be my imagination," she'd said. "Lucky me."

I'd been wondering about that ever since, but now that the boxes had my undivided attention, the problem was obvious.

No baffles.

How Dorade's work.
(WikiMedia Commons)

To filter water out of the air, Dorades need to be a sort of maze that air can get through, but water can't. The air goes through the maze and down the vent into the cabin, while the heavier, less agile water just gives up and runs out the drains at the base of the box.

But my boxes didn't have any baffles. The air/water mixture could go through the cowl, and straight into the vent into the cabin below -- right onto my darling's bunk! 

Solution? Add baffles.

New baffles in place

In the photo above, you can not only see how great the boxes look varnished, but the new baffles installed. They are just a piece of plastic, held in place by two plastic brackets. All easily fabricated. These were made by Larry, Howdy's partner, before I could get the chance to do it myself.

The baffle top is level with the top of the box, but there is a small gap under the baffle. This is all that's needed to turn my vent boxes into Dorade boxes.

Dorade box with cover on

And that's what it looks like when reassembled. You can see that the air/water mixture can enter the cowl, then it has to run the gauntlet down under the baffle, and then up and over the vent into the cabin. Air can make it, but water can't.

And that, I think, is the way small maintenance jobs should be done on a boat. No shortcuts, no 'miracle' cures. Just fix whatever needs fixing so it stays fixed for a good long time. And if you can improve it at the same time, all the better.

As I have said before, easy is overrated.

And there can never be enough varnish in the world.

You can quote me on that.

Meanwhile, it is blowing like the Dickens tonight. 20+ knot gusts. Glad we are tucked up in a fairly protected spot. We've got our alcohol heater working, the cabin is toasty warm, Christmas lights lighting up our cozy cabin. My best friend smiling across the table from me... Yes, all is right with the world.



Next Up: Breaking the Ice



2 comments:

  1. Wow! 700+ people following! If memory serves correctly, there were 70+ when I started following. My best friend (wife) and I will never have the luxury of your sailing adventure, however we did buy a small home in Florida's panhandle. We look forward to the day we can retire there.

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    1. Actually, it’s more like 1500. I haven’t updated that sign up form for many years. Good to have lots of folk watching over us.

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