Community Forums

dp7 · 02-12-2021, 12:15 PM

While planning a Seelevel install I noticed that the black & gray tanks have seams running around the perimeter. It appears that the upper & lower parts of the tanks are bonded to a flat sheet & then the seam is ground down to be somewhat flush. A portion of the unground flat sheet is visible in the second picture. Curious why there is a seam, unlike the fresh tank that is rotomolded without any seam. Perhaps the holding tanks are molded as a clamshell to allow insertion of an internal baffle. If so, wonder if that would interfere with the seelevel reading. Anyone have an insight on this?

Capt. Bill · 02-12-2021, 04:18 PM

Your black & grey tanks are PVC molded- they are made in two pieces to accommodate the sloped to drain bottom in them. They are hot PVC welded at the seams completely around the perimeter. I think they would then leak test them in a water tank using about 5-8psi air pressure inside to detect any leaks.

Your fresh water tank is poly propylene & is blow molded with all flat sides & ends.

Happy Trails

dp7 · 02-13-2021, 02:02 AM

Quote:

Originally Posted by Capt. Bill

Your black & grey tanks are PVC molded- they are made in two pieces to accommodate the sloped to drain bottom in them. They are hot PVC welded at the seams completely around the perimeter. I think they would then leak test them in a water tank using about 5-8psi air pressure inside to detect any leaks.

Your fresh water tank is poly propylene & is blow molded with all flat sides & ends.

Happy Trails

Thanks Bill. The fresh tank is rotomolded in one piece without seams. Why isn't the black & gray tank molded the same way? Rotomolded tanks can have sloped bottoms just as easily as parallel surfaces. It appears that the bottom of the tanks are not sloped. The slope is provided by angling the mounting rails.

So why is there a flat sheet sandwiched between the the two sections?

Steele · 02-13-2021, 06:49 PM

In my case those seams have caused the seelevel strips to fail. Garnett advised me to sand them flat before I replace the one that the seam damaged the diode.

Also Newmar told me that this is not virgin material and one of the reasons the sensors can read improperly was foreign material in the tank plastic.