AirHead Installation in Cape Dory 30

[CD30C]

I did this work in the spring of 2016, and at the time, didn't think of writing it up and putting it online. Recently, I was asked about this work, and started writing an email to describe it. When I got to the third page, I decided it would be best to put it on capedory.org. Capedory.org has been very helpful to me in the early days of our Cape Dory ownership. Recently, however, we have been studying more about navigation and foreign countries. This effort is a small way to pay back capedory.org. A warning, I don't log on very often, so I may miss any comments left here. I could not find any pictures; the boat is in Plymouth, England, and we are home in Charlottesville, Virginia, so I can't take any pictures for a long time. Sorry.

We have a 30 foot Cape Dory cutter which came with a typical holding tank toilet system in poor repair. Initially I replaced the hoses, cleaned the tank, and increased the size of the vent to encourage air (oxygen) to get into the tank, but none of this really worked, and when the wind was blowing from the vent toward the cockpit, the smell would turn the stomach of a vulture. Clearly, this kind of system, where you keep smelly liquid poo INSIDE the boat is a bad idea. I took a long hard look at the various types of composting toilets, and picked Air Head solely on geometry. I measured the angle of the hull in the head and compared it with both Nature's Head and Airhead. They both had tanks that had an angle cut off the back, but Air Head's angle matched the Cape Dory 30 much better. I also purchased the larger pee tank, with the understanding that I could exchange it if it didn't fit, but I didn't need to. I took out the old toilet and tank (where chain now resides), and inspected things. The boat liner had been cut away a bit to accommodate the old toilet. I found I had to cut away a bit more to accommodate the new toilet. I also angled it a bit (5 or 10 degrees aft I think), and when it was installed, I had to flex the head door about 3/4 inch to get it to latch. This is a nice feature since it keeps the door from rattling underway. A few more details:

0) I got the airhead with the handle on the right (forward) side, the tank with the beveled back, and the large (standard) size pee tank.

1) Optional: The mounting system seems a bit wobbly, since the brackets will not compensate for the head being set on an uneven surface. You certainly could put some polyester body filler down before setting the toilet in place. The Poly Polypropylene tank shouldn't stick well, and it should be possible to get it off when the filler is not quite set. What I did was to make a fiberglass/polyester pan by turning the tank upside down, taping it thoroughly with polyethylene packing tape, and covering the bottom with 4 or 5 layers of fiberglass. I think I embedded the brackets in the fiberglass at the same time. I then epoxied the pan to the boat, and bolted the tank to the pan. Measure twice!

2) The hardest part of this installation is the vent, or perhaps I made it hard because of my persnickety nature. I pondered this for quite a long time, and this is what I did. I am not recommending you do the same. I took out the Dorade vent from the wood box, fixed and varnished the box, and replaced the Dorade with an "SVB #17031 - Deck Ventilator" 80 Euros from Germany. This was the only one I found that fit on the box. I could have used the flexible hose out the left (aft) side of the tank, up to the vent, but the fan shroud didn't fit anywhere inside without building another box on the inside. Being an electrician, I am fond of using grey PVC conduit for boat plumbing. It is a nice neutral color, is UV resistant, and is exactly the same size as PVC plumbing pipe, and will accept all the same fittings in 1/2 3/4, 1, 1-1/4, 1-1/2, 2, etc sizes. I came out of the right side of the toilet with the flexible hose that came with the toilet, and into the fan shroud mounted on a 5x5 inch (special order) grey PVC electrical box mounted behind the toilet on the right side, just behind the crank. From the box, I routed 1-1/4 (I think) grey conduit aft toward the bulkhead, starboard along the bulkhead, and up to pass through the existing vent and a couple of inches into the box on deck. I made a board for the bottom of the box, to seal the pipe completely. When routing this pipe, I made use of my electrician skills and bent the conduit using a heat gun. This was fairly difficult even for me, and if you try this, you should approach it with a philosophical attitude, that you will have to do it two or three times to get it right (fortunately, conduit comes in 10 foot lengths). Use a real electric heat gun, with lots of ventilation. PVC puts off nasty fumes. It can be done with a propane torch, but it is much harder to control the heat, and of course there is fire to worry about. Do NOT skip the vent. Do NOT do a sloppy job of the vent. We have used this throughout a trip to the Bahamas, the Caribbean and Europe, and have never had bugs in the media. There must be no way for insects to find their way into the toilet. Do not leave the seat open between uses.

3) Electrical hookup: I wired this directly to a fuse on my panel, but not through a switch or breaker so there is no way to accidentally turn it off except by removing the fuse. So long as the battery is on, there will be power to the fan. I also use this circuit for my car stereo which has a wire that should be powered at all times to remember its settings. The two of these loads together are something like 0.1 A or one Watt. I find that any solar panel large enough to keep a battery charged, can keep up with this load, and keep the fan running at all times.

4) Eventually my wife and I got tired of wedging ourselves around the two doors in the cabin, and we decided to remove them. We feel privacy is overrated anyway.

5) Smell: Under normal operation, the toilet will issue forth a smell something like really fertile potting soil. It is not very strong and will only be smelled on deck in the vicinity of the vent. However, when we are living onboard, as the tank starts filling up, it will start transitioning to a more familiar poo smell. This is how you know when to empty the tank and replace the media. We don't like to put this stuff in the trash, since we believe that most trash nowadays is inspected for recyclable material by some other human being, and of course we don't want to dump it in the harbor, so we have to carefully time our dumping procedure with times we are offshore 3 miles. This means we occasionally have to dump the toilet when it isn't quite full. This is not the most pleasant of jobs, but isn't too bad. You just give a hard shake over the side of the boat, and it comes out in one sploosh.

6) Media: We like the coconut coir bricks which can be found at garden supply stores, AirHead, or online. When we were in the Bahamas, we nearly ran out and started using sawdust we collected off the ground at a boatyard. We found this to work great, the only downside was that it took up more precious storage space than the bricks. When you use the bricks, soak them in a bucket overnight. If you put a dry brick in the tank, and add water, you will have hard spots and won't be able to turn the crank. As you use the toilet, try to keep it fairly dry. It is OK to get a bit of pee in the poo tank, but don't let it get soupy.

7) The pee tank: We empty this daily when we think about it, otherwise every other day. We keep a flashlight in the head to check this. When we are in a marina, we dump it into their septic system or toilet, otherwise we dump it overside. This is a grey area and we don't like doing it, but we do it anyway.

8) Sitting: I am 6' 2", and Salli is 5' 7". I have plenty of headroom. On a Starboard tack, it is fairly easy to use, on a port tack, I need to brace myself by jamming my feet on either side of the head, or hanging on. It isn't too bad. Salli hasn't ever complained.

[Jim Walsh]

Ahoy Olive Oyl. Glad to hear you made it safely to Plymouth. It would be great to see something of your adventures across the North Atlantic here on the forum. Meeting you and Salli in Bermuda was one of the highlights of my trip to Bermuda. I’d be there now if it wasn’t for the pandemic.

[username]

Greetings,

I started the Airhead install on Amiable last year, and haven't been able to finish it yet due to COVID restrictions - getting to the boat is difficult. I chose the same unit you did. I need to finish the patch from the removal of the seacock. I installed a solar vent near the dorade box- fairly low profile, and I will place the supplied vent fan inline with it. I also found a 120 AC adapter from some forgotten gadget with the appropriate output, as there was a shore power outlet installed in the head. Your PVC idea is intriguing.

The removal of the storage tank created a lot of new space below the v-berth as well- I could lay in a large supply of coco coir there and still have space available.

I'm glad to hear that it's been working out for you!

Ian

[ghockaday]

We went a simpler route but we don't take extended cruises. We made a cabinet and a lid (johny house) that contains a 5 gallon bucket with a liner and clumping kitty litter. Dispose of as you would your litter box. I don't notice any smell at all. The old sewage take made the boat smell horrible. This is our 3rd sail boat and we have removed the marine head everytime. We also removed both doors for the same reason of getting by them. Dennis