ABS Pipe for sanitation runs

[AKA-None]

Originally Posted by Cheechako

Plastic should be as good or better than anything flex IME. BUT, I would not do long runs, break up the length with flexible hose. ...it's rigid and boats change shape when sailing etc!
Avoid the black stuff, it cracks readily from my home experience.

The grey PVC is tough but I have seen multiple failures in industrial applications using schedule 80 thick wall. I think the problem was vibration though in those instances. It was low pressure.

Right

You need flex built in there somewhere rather than ridged from end to end

Even ships have flex sections unless it all ties into a single gram separate from the ship itself

[mcm]

I lost the sale of a boat due to pvc piping rejected by survey in the sewage system, too low a flame and smoke spread rating, do not forget that this pipe connected to a thro hull can melt off and create a dangerous situation, there are numerous occasions when pvc piping will not even be accepted in high rise residential construction. The odd thing is that corrugated crappy piping is accepted for bilge pump discharge which I have had leak at the discharge end.

[boatpoker]

Wow ! so sad to hear ABS will fracture. We did three round trips from Toronto to Honduras and two round trips to Bahamas on this C&C custom trawler with ABS and never had an issue.

We are now in NJ on our fourth round trip from Toronto to Bahamas on this Benford 38 Fantail and never had an issue with ABS. I guess I better replace it right away !

[boatpoker]

Originally Posted by mcm

I lost the sale of a boat due to pvc piping rejected by survey in the sewage system, too low a flame and smoke spread rating, do not forget that this pipe connected to a thro hull can melt off and create a dangerous situation, there are numerous occasions when pvc piping will not even be accepted in high rise residential construction. The odd thing is that corrugated crappy piping is accepted for bilge pump discharge which I have had leak at the discharge end.

Unless it was in the engine compartment your surveyor was wrong. There is nothing in ABYC, Transport Canada TP1332, US Title 33 or Title 46 Code of Federal Regulations to support that. Plus previous comments here have said the ABS or PVC has several inches of hose connecting it to the throughull.

[Rumrace]

Sorry. To be clear the heavy hose between your tank and the deck hardware where the pump out collar is attached is vital. The old Black one came from aviation the red one I think DuPont , modern blue silicone I’m not sure but it’s a short list.
ABS is a polystyrene weak as heck really. Fails under sunlight just fine buried in walls
Neither Polystyrene likes the cold which I’m guessing is why a polyvinyl is used. Hard to argue with the Epoxy family.
But go ahead I have their number

[AKA-None]

Originally Posted by Rumrace

Sorry. To be clear the heavy hose between your tank and the deck hardware where the pump out collar is attached is vital. The old Black one came from aviation the red one I think DuPont , modern blue silicone I’m not sure but it’s a short list.

ABS is a polystyrene weak as heck really. Fails under sunlight just fine buried in walls

Neither Polystyrene likes the cold which I’m guessing is why a polyvinyl is used. Hard to argue with the Epoxy family.

But go ahead I have their number

Ahhh my misunderstanding I thought you meant on the outside not from the tank to the pump out fitting
Thanks for the clarification

[akopac]

I found the certified hose for $5/foot in LaPaz, MX bought 20 ft. And replaced all my hose.the last hose I bought was 25 years ago in La Paz. I think I got my moneys worth.

[skipgundlach]

Just a quickie:

Flying Pig survived a red-helicopter wreck of 3 days, ~3-5000 impacts on a flat rock in 8-10' surf, with all PVC.

I did the transitions by carefully shaping the ends, and using drain collars (a rubber sleeve) with an extra hose clamp over the butt-joint connection, as well as at the ends of the sleeve, as is the sleeve is designed.

I made the external pipe and the toilet exit the same size by slipping a short sleeve of regular hose over the nipple; the butt, then, matched up.

My picture gallery server took a dump or I'd refer you to the job. NEVER a head smell aboard Flying Pig, even in the days well before that magic hose Peggie referred to earlier.

As to clear pipe, here's a view of the exit of the forward head, seen as I pulled the Y-valve, to replace it, 15 years after installation; the second shows the sleeve:

The secret is to pump, a LOT, to remove the effluent, and to follow it with the same number (or until the through-hull burps) of dry pumps. If your anti-siphon valve is in good nick, you then have a dry stack, with the pressure keeping the valve closed...

[skipgundlach]

Just a quickie:

Flying Pig survived a red-helicopter wreck of 3 days, ~3-5000 impacts on a flat rock in 8-10' surf, with all PVC.

I did the transitions by carefully shaping the ends, and using drain collars (a rubber sleeve) with an extra hose clamp over the butt-joint connection, as well as at the ends of the sleeve, as is the sleeve is designed.

I made the external pipe and the toilet exit the same size by slipping a short sleeve of regular hose over the nipple; the butt, then, matched up.

My picture gallery server took a dump or I'd refer you to the job. NEVER a head smell aboard Flying Pig, even in the days well before that magic hose Peggie referred to earlier.

As to clear pipe, here's a view of the exit of the forward head, seen as I pulled the Y-valve, to replace it, 15 years after installation; the second shows the sleeve:

The secret is to pump, a LOT, to remove the effluent, and to follow it with the same number (or until the through-hull burps) of dry pumps. If your anti-siphon valve is in good nick, you then have a dry stack, with the pressure keeping the valve closed...

[ranger58sb]

Originally Posted by Rumrace

When you pump out you thread a collar into the deck hardware.

Originally Posted by AKA-None

What?
Around here it’s a rubber fitting on the pump out that seals into the boat fitting

You remove the screw in deck cap and that’s it

There is nothing else

Yes, not as common but some pump-out stations around here do indeed thread another fitting into the boat's deck fitting... and then the pump-out hose clamps to that.

It's a relatively positive connection, and the operator (boat person or dock person) doesn't have to hang around holding the hose up against the deck. Not uncommon for that to be the dock person who can then temporarily wander off to do other chores (fuel, other boats, whatever).

-Chris

[skipgundlach]

We have one of those fittings on Flying Pig, though I've never used it...

[rslifkin]

Those screw in fittings are absolutely wonderful for those of us with large holding tanks (when using one is an option).

[AKA-None]

Learn something new every day

[sailingharry]

We carry one on Circe. On this trip, up the Erie Canal and down the St lawrence, we used it more often than not. A 3" long fitting, screws into the deck fitting and has a groove that accepts a cam lock suction pipe. Pretty slick actually.

I think this is the exact one we have
https://www.amazon.com/AMRS-31034350...dp/B00NJ7SQV6/

[skipgundlach]

Originally Posted by sailingharry

We carry one on Circe. On this trip, up the Erie Canal and down the St lawrence, we used it more often than not. A 3" long fitting, screws into the deck fitting and has a groove that accepts a cam lock suction pipe. Pretty slick actually.

I think this is the exact one we have
https://www.amazon.com/AMRS-31034350...dp/B00NJ7SQV6/

Yup, that's what we have as well.