Bathstore sink query

[trigger25]

I've just fitted a new slotted basin waste and aligned the slot towards the overflow hole in the sink. The overflowing water doesn't go out fast enough and could spill over if the tap is left on too long.

The basin is a Bathstore one and when looking at it before fitting the waste I noticed some slots in the waste hole (might have been on the sides 90 degrees to the hole in sink) but I can't remember where they actually were.

Can anyone who has seen one of these sinks advise me how the basin waste should be aligned. I don't particulary want to remove the waste just to see.

Thanks
Trigger

 

[JCplumb]

My guess is that the channel that the overflow takes is not fit for purpose, half the sinks I see these days have a really poor overflow, mine included although it was a cheap chinese import, if that's the case there's nothing you can do other than get a different sink, or use valves to reduce the speed that the water can come through the taps.
To test - take the waste out completely, have a bucket ready underneath and cover the plug holewith a plunger or even your hand then open the taps. If the water still comes out faster than the overflow can handle, then there's not a lot you can do.
It's impossible to identify your basin from the description you give, but I have fitted bathstore stuff before and what I've seen looks good but there never seems to be much thought for the installer or the regs. One example was a cloakroom sink with no overflow and slotted waste??
Lining up the holes in the basin waste and the exit from the overflow won't give you a massive difference in the capacity of the overflow.
You could also fit a running basin waste which is designed for sinks with no overflow, however you won't be able to fill the basin up as there will effectively be no plug.

 

[trigger25]

Thanks for the detailed reply and the various options.

The new basin waste has two much larger slotted holes and one is aimed at the overflow hole in the sink. I think there's enough space around the waste itself as to not matter if it wasn't aligned correctly. The original basin waste had four much smaller holes, each 90 degrees apart.

It also depends on where the water comes out of the basin internally from the overflow hole and without taking the waste back out I won't know. I never tried the overflow capabilities with the original waste as it's something that I would never thought of doing.

As a first option and the easiest for now I might experiment and reduce the rate of flow from the tap using the inline shut off valves and see what happens.

Thanks
Trigger