Spin Welding fittings

[cody]

I'm going to be adding 2-100 gallon tanks to the bus and I can buy them from Bontragers for about 60 bucks each, the problem is the shape I want, they only have in fresh water tanks, basically rectangular about 2ft wide by 2ft tall and fairly long, I want to use them as a grey tank and a black tank so I would need the drain fittings spin welded in (I'm not sure of the security of the glue in fittings), my question is does any one know of a place in the elkhart area that does this kind of thing, my preference would be to buy a regular waste tank but I'm trying to avoid the high cost of that, especially when I can get them so much cheaper from bontragers.

[jmblake]

Cody
 Master Tech Rv in Elkhart did mine a few years back not sure of price because I got the tanks from him to. Web site is  www.mastertecservices.com

[Hartley]

I have spun my own fittings in with a home-made fitting adapter, hole saw
and good fast 3/8 electric drill and they worked every time.

It is good to practice on waste plastic first however until you get the
hang of the method.

[TomC]

On my big rig truck, I had a 20 gal black tank and a 25 gal gray water tank-both rectangular.  I had El Monte Plastics make the tanks and spin weld on the fittings.  The only problem with using the rectangular tanks for black is that the drain is not at the bottom of the tank, hence you can't ever get it to drain all the way-unless you're on a rather steep hill.  This causes the solids to build up on the bottom of the tank, thus reducing the capacity of the tank somewhat.  The best is to have a black water tank made with the slope towards the drain built into the tank so the tank can completely evacuate every time.  I have this design on my bus and it is definitely superior to the rectangular tanks I had on my truck.  But-the rectangular tanks will work-just not as efficiently.  Good Luck, TomC

[cody]

I've solved the drainage problem in the past by building a slight slope into the cradle that holds the tanks, I would rather save the several hundred dollar difference and use the tanks from bontragers if I can.

[johns4104]

Hey how about tilting the bus to drain!



Have fun John

[cody]

Lol john, maybe if i kept the 24.5 wheels on the passenger side and then changed the drivers side wheels to 22's I'd get a little tilt for the drainage lol.

[belfert]

A lot of the commercially manufactured tanks are polyethylene and difficult to weld.  I wanted to cut a hole in the top of my tank to install a fitting and then have the hole covered and welded, but the places that weld plastic said polyethylene will most likely crack at the weld.  I don't know if spin welding would be an issue or not.

[gus]

The 3" screw in fitting in my waste tank is installed with rubber washers for seals and works fine. I think the tanks are polyethylene farm spray tanks.

My tank is unusual in that the sewer drain pipe goes down from the toilet, across the bus and down to the bottom of the tank. Weird but it works very well.

The slope of the drain is very small. It wouldn't appear to work at all but it has never caused a problem in 3 1/2 years. I just make sure to use plenty of flushing water.

The input to the tank and the drain are both on the same line.

The tanks have a large fill opening at the top so you can reach in to install the inside part of the fittings. Seems to me to be a pretty good system and was installed by the PO.

[Hi yo silver]

John, I've heard of training wheels, but DRAINING WHEELS?? LOL