Author Topic: I ready to start the plumbing...  (Read 2679 times)

Offline Danny

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I ready to start the plumbing...
« on: July 04, 2006, 08:18:59 PM »
This may seem like elementary questions, but -

(1)  You buy a black or gray tank with no fittings and then add them in the location you need them - is this correct?  Would the fittings glue on with PVP or CPVP glue as standard plumbing?

(2)  Can the tanks sit on the floor of the bay or do they need to be elevated to assist in them dumping?

(3) Where is the best place to buy the waste and clean water tanks?

I have heard it said, "life comes at you fast".  I didn't know it would be in the shape of a bus  :-)

Offline TomC

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Re: I ready to start the plumbing...
« Reply #1 on: July 04, 2006, 09:00:47 PM »
(1)- the fittings (at least from Ardemco and El Monte Plastics [both in Los Angeles area]) are spun on with a drill motor.  Meaning they spin the fitting against the hole and the heat from the friction causes the tank plastic to melt at that point, and when it cools, is welded on.
(2)-they can sit on the floor since the sewer drain is lower than the bus.  You can just use a rectangular tank for the gray and have that sit on the floor.  But it is suggested that the black tank be elevated a bit since a properly built black tank should have the base slanted towards the 3" opening so to be able to completely evacuate the tank every time it is emptied.  The gray tank is not so critical.
Good Luck, TomC
Tom & Donna Christman. '77 AMGeneral 10240B; 8V-71TATAIC V730.

Offline JackConrad

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Re: I ready to start the plumbing...
« Reply #2 on: July 05, 2006, 05:08:33 AM »
    Most of the plastic tanks use spin-in fittings. I just used a system called UniSeal to install a couple pipes in the top of a black water tank. I drilled a proper sized hole with a hole saw, installed the UniSeal, lubed it with dish soap and installed the pipe. I don't think I would trust this for a fitting in the side or bottom of the tank.
If you are on the west coast Ardemco or El Monte, if you are on the east coast Dura-Cast in Lake Wales, Florida. You can also check with local agricultural supply companies. They use similar tanks for fertilizer and chemical uses.  Hope this helps, Jack
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Offline DrivingMissLazy

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Re: I ready to start the plumbing...
« Reply #3 on: July 05, 2006, 05:33:20 AM »
When I visited the plant in El Monte, they were using a router to spin the fittings in. Much higher speed than a drill motor and heated the plastic up a lot faster.
Life should NOT be a journey to the grave with the intention of arriving safely in an attractive and well preserved body. But rather to skid in sideways, chocolate in one hand, a good Reisling in the other, body thoroughly used up, totally worn out and screaming:  WOO HOO, what a ride


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Re: I ready to start the plumbing...
« Reply #4 on: July 05, 2006, 08:59:57 AM »
The other day I was working on a friends Newell coach. The top fitting for the grey water sight guage was FUBAR and I didn't have time to order a new larger fitting.
I tried different methods of putting a new fitting in but didn't see a way to really make it strong or tight.
Since this had to be done within a time limit, I ended up buying a larger off the shelf PVC fitting and swiping a small chunk of the same kind of plastic I was working on.
I used my new plastic welder to attach the 3"X3" chunk of plastic to the tank and drilled a hole slightly smaller than the fitting I was going to install.
Next I took my plastic welder and heated the new plate and tank up and screwed the new fitting in until it was bottomed out in the soft plastic.
After that I screwed it back out a couple of turns and then let it cool.
Once cooled, I tried to remove it with an end wrench and really cinched down on it. I couldn't move it at all, even when hanging on to the wrench and jumping up and down.
When I had hooked everything back up again, I filled the grey tank with water and closed the valves and plugged the drains so that there was no way to relieve pressure. I then pounded on a 4"X4"X24" wedge to make more pressure and never had a leak.

I wouldn't use this method for a pressure system but it did work for a grey water system.



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Re: I ready to start the plumbing...
« Reply #5 on: July 05, 2006, 01:46:57 PM »
My question is, m' would Cat have handled the situation if your 'cave man' test had not substantiated in the end result? ::)

My guess is...copious amounts of tomato juice, applied generously and a GI shower with lots of pressure. :-\

Mmmmm, glad it worked out! ;)