Dumb toilet ("head") question

[bruce v]

Originally Posted by catsketcher

No ideas is ever ridiculous and some ridiculous ideas find their way back in favour - foils took 50 years to be viable in multihulls (Search Dave Kieper and Wiiliwaw if you want a trip down multi history)

Most boat toilets are below the waterline and need pumping UP to get the waste out of the toilet. As normal toilets are gravity fed they can't work in this way. On my cat the top of the toilet is 100m above the waterline (it helps not sink the boat) but I still couldn't use a normal dunny.

If you decided to put the toilet on the bridgedeck then go ahead. It will work especially well if you plumb it straight down. I have heard of Hitchiker 40 with this arrangement. You could even plumb it into a holding tank that was also above the waterline so you could discharge easily when sailing. (That is what we do when cruising - holding tank on when anchored, discharge at sea when 5-10 miles away from anywhere doing 6 knots or more with a gravity discharge tank).

So if you have a space in the bridgedeck then go for it but there are few cats with bathroom soles high enough for it to work.

cheers

Phil

I hope you made an error 100m = 100 meters or just over 300 feet. That's either a marvelously large vessel or you have your toilet up the flagpole. Even the largest of cruising Cats don't have masts over 75'. LOL.

Truthfully, it sounds like you are bankrolling a venture into curiosity. For a lot less monies, a lot more space saved and a lot less concerns about environmental pollution, you ought to consider a quality composting head. Of course, if you are just blowing smoke up our backsides, I could also suggest an incinerating unit. They say you can even use then while incenerating (watch for toasted buns). In reality your idea could work under most cercumstances but there will always be those situations (even where you thought you were stable) that rocking and rolling create uncontrollable slosh and an unexpected butt wash.

[Mike Banks]

I have seen it done on some vessels but it does not comply with most marine regulations that require excrement and the tissues to be macerated even if discarded well offshore.

I had a pal with a reef charter vessel and they used the fancy TMQ version of electric pedestal type in their vessel, and stored their treated macerated waste for pump-out in port. They replaced the macerator pumps every two years regardless, when they also replaced all of the ships batteries, because it could be done quickly during routine maintenance when the vessel was pulled out of service.

I have had my two electric TMQ's for eight years of moderate use and never replaced anything, but I have had a spare head sitting ready in case I should need to. The complete head ready to install is only a little more expensive than the replacement pump and hoses. Prior to the electrics I had a pump-out system--which was vastly inferior.

The only thing with electric heads is the need to make sure nothing goes in there that has not been digested or is designed for use in a marine toilet system. Sanitary pads and condoms etc are not good things to remove from a stripped down pump at sea or ashore.

[Blackduck]

Originally Posted by Kenomac

Where are you located? I'm also up an estuary here in Italy.

Until a week ago I was in the river Krka near Skradin, now I am at Murter, Croatia

[captlloyd]

Originally Posted by bruce v

I hope you made an error 100m = 100 meters or just over 300 feet. That's either a marvelously large vessel or you have your toilet up the flagpole. Even the largest of cruising Cats don't have masts over 75'. LOL.

Truthfully, it sounds like you are bankrolling a venture into curiosity. For a lot less monies, a lot more space saved and a lot less concerns about environmental pollution, you ought to consider a quality composting head. Of course, if you are just blowing smoke up our backsides, I could also suggest an incinerating unit. They say you can even use then while incenerating (watch for toasted buns). In reality your idea could work under most cercumstances but there will always be those situations (even where you thought you were stable) that rocking and rolling create uncontrollable slosh and an unexpected butt wash.

oK, here we go, off to the races. Composting head on the rail, conventional head on the outside, they are neck and neck at the quarter...........
(My money is on the composter)

[Thumbs Up]

If you want to flush your marine head with fresh water just reach over and grab the handheld shower or put a pull out faucet on your sink and squirt the water in while you pump. Another option could be to plumb a tee and a valve into the tubing going into the bowl then if you want a freshwater flush open the valve for a second. Another consideration is to rig a small cistern as you said but no need to place it above the toilet as the pump on the toilet should be able to pull the water up. Or how about using grey water (dishwater) to flush? You could set the float in your greywater sump so that there is always enough water left for a few flushes. The problem with saltwater isn't smell it is the scale that forms when mixed with urine. By using freshwater you should be able to reduce the volume of each flush which could give you more time between pumpouts. Another big advantage would be that if you eliminated the seawater intake to the head then that is one less way to sink your boat! Some people that replied think that you are talking about using a gravity flush toilet but I think that you are just talking about using a gravity fed fresh water tank to feed the inlet on a marine head. If anyone does want to use a gravity flush house toilet you can buy low flush models that have a pressure tank instead of a reservoir in the tank so there is no sloshing around. You would need to install directly over the tank. I have installed them in a day tour catamaran in Hawaii, the owner switched over to these because of the endless problems with the tourists trying to use marine heads. Hey Catsketcher (off topic) you mention a Hitchhiker 40, do you have any source of info or design sketches about these boats? They are kind of an enigma to non Australians and not much info online. I am asking because I own one and am always trying to find out more about it. It is currently for sale. (in Mexico)

[Fore and Aft]

The biggest problem with a domestic toilet is the amount of water they use with every flush. That could be an issue depending on the size of your grey water tank?
I have a Y valve on the sink in our head and when we want a fresh water flush we just fill the sink and flush the toilet. In the marina we have the toilet on permenant fresh water flush. A bit of toothpaste and hand soap seems to keep it clean.

Cheers

[StuM]

Originally Posted by Thumbs Up

If you want to flush your marine head with fresh water just reach over and grab the handheld shower or put a pull out faucet on your sink and squirt the water in while you pump.

As another poster said, when in regular use, sea water doesn't sit long enough to be a problem. You only need fresh water if the head is going to be left unused for days.

So using the freshwater shower/sink faucet before leaving the boat for any length of time (or when guests depart and one head will no longer be in regular use) is a simple and effective solution.

[catsketcher]

Yes I did mean 100mm - can't get away with anything here.

Whilst we are on the topic of loos I thought I would venture something else - using a "bum gun".

On Kankama we have a pressurised freshwater shower on a hose that is long enough to lead out through the toilet window and use for washing down after swimming. We also use it to wash instead of using toilet paper - it is much cleaner for us and also it means that we never worry about getting the toilet clogged. Instead of reaching for the dunny paper we reach for the shower head and instant bidet.

I am not sure why we use something that clogs and doesn't clean as well as water. We keep meaning to put one in our home as well.

cheers

Phil

[Kenomac]

Phil,

Just spring for the macerating head. No clogs in six years, just push a button.