Water Tank Material
- Thread starter WasabiRush
- Start date
All boat builders OEM and "stock" (not custom one-off) plastic water and waste tanks are actually LDPE. Custom welded tanks are usually PP because PP is easier to cut and can be "glued." PE must be heat welded 'cuz there is no sealant that will bond permanently to it.
--Peggie
--Peggie
The fuel tank isn't HDPE either...at least it hadn't better be because that's the wrong type of PE.
HD and LD PE is LINEAR polyethylene....fuel will permeate it enough to make it weep. PE fuel tanks must be made of CROSSLINKED PE and can only be made by a USCG approved fuel tank mfr, of which there are very few left in the US because they also have to meet certain USCG criteria, among which are all fittings must be ON the top of the tank, no surface on which liquids can pool (there are more, but those are the only ones I can remember).
None of the water and waste tank mfrs also make fuel tanks.
--Peggie
HD and LD PE is LINEAR polyethylene....fuel will permeate it enough to make it weep. PE fuel tanks must be made of CROSSLINKED PE and can only be made by a USCG approved fuel tank mfr, of which there are very few left in the US because they also have to meet certain USCG criteria, among which are all fittings must be ON the top of the tank, no surface on which liquids can pool (there are more, but those are the only ones I can remember).
None of the water and waste tank mfrs also make fuel tanks.
--Peggie
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Thanks for the info Peggie. And for WasabiRush in case you're asking because you have a problem here is some info about my desperate last minute solution to a leak. Not knowing what it was made off and having noticed a leak at an upper corner seam of the port tank on my 34 just 1 day before leaving on a cruise in 2021, being desperate and not having the time to have a new tank made, I opened up what then looked like a crack, then using the rope cutting blade on 2 soldering guns to generate heat, I successfully resealed the leaking area. For good measure because even though I filled the tank to capacity to test it, I used some aquamend to cover the weld I had done, then covered the whole thing with Gorilla tape ! Excessive jerry-rigging yes, but it did work and has been leak-proof since !
I'm asking because my vent hose nipple is cracked and leaks. As I've been researching solutions, I've discovered that not all plastics are equal.
By "nipple" are you referring to the female fitting in the tank? Or the male hose fitting?
--Peggie
--Peggie
Since I was part of the manufacture of Both types of PolyEthene.
LD= Low Density LDPE
HD=High Density HDPE
Both are called
ThermoPlastics
This means both types can be heat molded to form shapes.
Jim...