water tank mounted

[kiltedhiker]

I was thinkin about a water tank and that gave me a Idea on how I want mine
Thanks MJ!

[madjack]

...ok, ok, ok already ...Yes the tank is mounted flat against the floor, we considered making one side higher for better flow but during tests we found that it didn't seem to matter...even flat mounted, 99% of the water came out.

Yes there have been some mods since the original pics were put up...they only affected the fill location...in the original pics the fill was on the end and one end was shorter to allow room for the pump...in the new pics there is a coupling in the pic and the fill is located in the top center of it, the reason for this was to keep all things mechanical in the center cabinet of the galley and not take room out of the side cabinets which are shallower than normal because of a 3.5 in curve under in the front and a 6'6" sleeping compartment.

The fill fitting is a 1.25" MIP X male insert fitting, the others are 3/8 MIP X male insert fittings...all of them along with the clear tubing was picked up from the local ACE Hardware store...the mounting block for the pump is a piece of 2X decking made from recycled plastic, Gorilla glued and screwed to the bottom of the floor...

Dale, the plugged hole was originally gonna have the pump screwed into it...now the pump is remotely mounted and there is a supply feed on the bottom and a vent on the top...

Ira, I don't have any pics of the modified tank but will get a couple of pics of the fill where it comes up thru the floor along with the supply line...

Mike, here is a tank capacity calculator;
http://www.watertanks.com/calc.asp
...you can stack fittings together (T.s and such) to increase capacity and if you go up to 6" pipe you effectively double the capacity for a given length

the sch 40 PVc is 1/4 thick as are the fittings...this gives plenty of meat to drill and tap for threaded fittings...the 3/8th tap we had...the 1.25" tap cost 30 bucks on a "deal" sale...
madjack

[cracker39]

MJ, there are several things about your tank that I like. First, it's unique. Second, It's cheap top build. Third, being under the floor, it doesn't take up any space inside. Fourth, it can be retrofitted to a trailer later very easily. Number 4 is my favorite, since I am not putting in a sink or tank now, but thought of adding one later on. One can be constructed to fit into one of my 2' x 5' spaces between sides and cross members, close to the center so it won't drastically alter the balance. Or, make two 4' tubes with a 1" connector tube, and hang one each before and aft of the axle to keep the same balance. My floor bolts through cross members and welded on flanges are perfect to hold the hangers. I've even thought of using a smaller diameter PVC, and more length for the same volume of water. With 3", I'd need 12' to equal the volume of 7' of 4" pipe.

I'm still curious as to the fill process. Do you connect a hose? If so, do you have an overflow outlet to show when it's full? I'm making some guesses here and doing my own version to see if I have it right.

Here’s my idea on how the PVC tank works. MJ, am I right or missing something? It’s not easy to make it clear in 2D and I’m not up to 3D CAD yet.

This is the 4” diameter “U” shaped tank, looked at from the end, and then the side. I have a 1/2” filler pipe coming into one end. At the other end, there is a 1/2” overflow, made of pipe and elbows with a trap similar to those under sinks. When the water comes out the overflow, you know that the tank is full. The trap holds water and keeps bugs from coming in the overflow pipe. A connector to the pump is in the bottom of the tank. If the tank is level, I guess it doesn’t matter where it’s located.

In my End View drawing the overflow pipe system is sticking out to the side. In reality, it can be angled 90 degrees at the first set of elbows to the side of the tank, and the remaining 3 elbows and down pipe can rest against the side of the tank. That is the way it is viewed in the Side View



My only concern, is with a tank that shape, with it hafl full, there is a lot of water that can slosh from one end to the other, putting stress on the hangers if they are not really strong. I doubt that 25 or 30 lbs of water moving around would bother the trailer balance though.

[cracker39]

Sorry, I posted this before I saw your new post.

[mikeschn]

Dale,

Nice sketches... I really like the concept!!! Now I might have to add that to the Lil Diner...

Mike...

[cracker39]

MJ, another question re the 1.25" tap. Thirty bucks is a lot to spend for just one small part. Why not drill into the tank, and insert and epoxy in regular PVC pipe (3/4" or 1") and put a hose connector on it (less than a buck total). Same for the overflow. I'm sure a plastic hose connector for the pump line could be gotten cheaply and epoxied in too. I'm not concerned with putting epoxy in the system, because I wouldn't be using the water in the tank for drinking or cooking, but just for washing purposes.

[Ira]

Dale, why are you concerned about the weight and the water sloshing around?

I would think you would just fill it when you get to your site, and drain it when you leave.

[Guy]

Dear Jack,

It is nice to see the tank in place. Good work.
I have two questions: Is the JC Whitney pump self-priming so that it does not have to be lower than the water level at all times?

Will you be insulating the PVC so that it does not pick up too much heat from the road? Or from the cold, if you choose to camp four seasons?

[Mitheral]

..the mounting block for the pump is a piece of 2X decking made from recycled plastic, Gorilla glued and screwed to the bottom of the floor...

Ah!

MJ, another question re the 1.25" tap. Thirty bucks is a lot to spend for just one small part. Why not drill into the tank, and insert and epoxy in regular PVC pipe (3/4" or 1") and put a hose connector on it (less than a buck total). Same for the overflow. I'm sure a plastic hose connector for the pump line could be gotten cheaply and epoxied in too. I'm not concerned with putting epoxy in the system, because I wouldn't be using the water in the tank for drinking or cooking, but just for washing purposes.

I've done the following in ABS making custom heaters for hot tubs: Drill a hole in the end cap the minor diameter of the threads of the fitting you wish to insert. Heat up the fitting, I use an Actelyne Turbo Torch but a regular propane plumbing torch would work. It doesn't have to be glowing hot, 200-300 degrees F is sufficient. Then slowly thread the fitting into the predrilled hole. Hold in place until the fitting cools enough for the plastic to set. I've sprayed the fitting with a mist of water to hurry things along.

[Guy]

Dear Ira,

Sloshing around can cause some pretty severe swaying while you are towing.

You do not want 30 or 40 (or more) pounds of water at the rear of your tear swinging left and right while you are driving.

[toypusher]

I have a 7 gallon tank and have always filled it prior to traveling and it has always been empty after a camping trip. So, I have never tried towing with the tank partially filled! Never had the occasion.

[mikeschn]

Dear Ira,

Sloshing around can cause some pretty severe swaying while you are towing.

You do not want 30 or 40 (or more) pounds of water at the rear of your tear swinging left and right while you are driving.

40 lbs of water is 5 gallons... Isn't that the size of MJ's water tank?

Mike...

[madjack]

Dale, the 1.25 tap...possibly but we figured that if we wanted to build more tanks for more applications, we would have the tap and yes there is a vent line which can be seen above the supply line...the fill on the side of the trailer is a marine water fill and you use a hose to fill it

Mitheral..that's a good idea...hadn't considered heat and thread...it would probably work just fine

Mike, yep 5 gals is about 42#s and I am not even worried about the sloshing since the water is contained in two legs which will act as a baffle and there is not enough volume/weight in either to be of concern...the strapping that holds the tank up is flat 1.5" strap like that used to suspend garage doors

Guy, the pump is not self priming which is why it is mounted whereit is
madjack

[Guy]

Dear Kerry,

Not every trip is to one place for a few days and then home. Many teardrops are used for longer term travel with one day stays and on. It is these cases that concerns about water weight balance arise. Madjack's system seems to handle this pretty well since he has the "U" to act as a baffle. Many high end water tanks are built with baffles in them to prevent this problem from arising.

[toypusher]

Guy,

I never really considered the potential of my tank being only partially filled and it never came up. Thank you for pointing it out and I will be aware of it in the future.