Why Are Long Radius Bends less than 90 Degrees?

[jonjack]

Hi

I am replacing an old soil stack and some underground drainage coming of it with upvc and have hit a bit of a snag and need a pro to explain my school boy error!

I have bought a long radius bend (eg. Double Socket Drain Bend 87.5Deg - Underground Drainage - Guttering & Drainage -Building Materials - Wickes) for the base of the vertical stack but because its 82.5 degrees it means I cant get it to fall away to connect up with the nearby existing salt-glazed which I reckon has about a 1:30 fall away. A 87.5 degree bend that connects to the vertical on one axis will then mean that the 'horizontal' bit coming off is going slightly upwards right?

Can you get a 92 degrees bend or something which would seem more logical in order to get a slight fall coming out of it? I cant find any such product at Wickes or Screwfix.

 

[REDSAW]

just use one of these
Toolstation > Roofing & Drainage > 110mm Underground > Adjustable Bend 110mm

 

[dancinplumba]

this thread is hilarious

 

[ecowarm]

The 87.5 degrees is taken from the other side, i.e. 180 - 87.5 = 92.5

 

[dancinplumba]

spoilt it

 

[Keefy]

Hey mate, you just sold me a pipe shaped like a boomerang.

 

[jonjack]

The 87.5 degrees is taken from the other side, i.e. 180 - 87.5 = 92.5

cheers mate, looks like I've got the soil pipe coming out the bottom end falling away too steeply then.

Thanks

 

[dancinplumba]

its gone funny again