- Sep 9, 2013
- 620
- 3,106
- Funster No
- 28,022
- MH
- Hymer S840
- Exp
- First moho 11/2013, second 11/2014 current from 09/2019.
I've just spent a few hours (while quite a few hours if you include thinking time) improving our black tank waste system.
I’ve replaced the weakest link in the system - the easily blocked 90-degree bend that enters the tank.
The pipe from the macerator is substantial with an internal diameter of 38mm...however, the 90-degree bend and entry to the tank is 23mm i/d.
I’ve blanked off the original 23mm tank entry with the rubber bung off a walking stick.
A 50mm diameter hole was cut in the tank access cap, the hole was enlarged to 53mm by filing to accept the tapered boss.
A flexible 90-degree 1.5-inch diameter bend was fixed to the tank boss and the new longer flexible pipe back to the toilet.
Here are some photos - not necessarily in the correct order - the parts were purchased from a fish pond supplier.
The small hole in the tank cap was for the tank level alarm. I don't think the tank alarm was originally in that position as in one corner of the tank there is an identical tank sensor. I’ve put the working one in its original location.
The cost of the parts was about £25
https://www.japankoiimports.com/.../flanged-tank.../
https://www.japankoiimports.com/.../elbow-1-5-evolution.../
https://www.toolstation.com/puraflex-40-pu-sealant.../p85566
The new 1m flexible, smooth bore pipe was bought from our local garden center/fish pond shop - the same diameter as the original.
A reminder of school maths lessons...area of a circle = π × r²
Circle area = π × r² = π × 1.32 cm² ≈ 4.155 cm² for the original 90-degree bend and the pipe into the tank.
Circle area = π × r² = π × 3.61 cm² ≈ 11.341 cm² for the new 90-degree bend and the pipe into the tank.
So I think the new setup is nearly three times the surface area (presumably).
Hopefully, I won't need to carry a supply of disposable gloves any longer.
DavidG58
Kim H
I’ve replaced the weakest link in the system - the easily blocked 90-degree bend that enters the tank.
The pipe from the macerator is substantial with an internal diameter of 38mm...however, the 90-degree bend and entry to the tank is 23mm i/d.
I’ve blanked off the original 23mm tank entry with the rubber bung off a walking stick.
A 50mm diameter hole was cut in the tank access cap, the hole was enlarged to 53mm by filing to accept the tapered boss.
A flexible 90-degree 1.5-inch diameter bend was fixed to the tank boss and the new longer flexible pipe back to the toilet.
Here are some photos - not necessarily in the correct order - the parts were purchased from a fish pond supplier.
The small hole in the tank cap was for the tank level alarm. I don't think the tank alarm was originally in that position as in one corner of the tank there is an identical tank sensor. I’ve put the working one in its original location.
The cost of the parts was about £25
https://www.japankoiimports.com/.../flanged-tank.../
https://www.japankoiimports.com/.../elbow-1-5-evolution.../
https://www.toolstation.com/puraflex-40-pu-sealant.../p85566
The new 1m flexible, smooth bore pipe was bought from our local garden center/fish pond shop - the same diameter as the original.
A reminder of school maths lessons...area of a circle = π × r²
Circle area = π × r² = π × 1.32 cm² ≈ 4.155 cm² for the original 90-degree bend and the pipe into the tank.
Circle area = π × r² = π × 3.61 cm² ≈ 11.341 cm² for the new 90-degree bend and the pipe into the tank.
So I think the new setup is nearly three times the surface area (presumably).
Hopefully, I won't need to carry a supply of disposable gloves any longer.
DavidG58
Kim H
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