Leaking Bath Waste

[leescortxr3i]

Hi all. Wonder if you can please offer me some advice regarding my leaking bath trap. I've assembled my bath trap as per the hastily drawn diagram below. It's on a free standing bath and I'm using the waste that came with the bath. As you can see, I put a very small amount of Plumbers Gold bon both sides of the rubber washer on the plug hole side of the assembly. I then put a larger bead of Plumbers Gold around the rubber collar underneath before tightening. When I say tightening, I'm unable to use a back nut as one wasn't supplied but I've used a thread extension piece that butted up to the rubber collar and seemed to tighten nicely. However after filling the bath with a few inches of water, I'm getting water leaking around the outside of the waste thread. I can only assume that the rubber collar underneath isn't pressing into the threads enough?

Have I applied the Plumbers Gold correctly please? Should I have thrown the rubber washer at the top as some online have said to do away with this and put a larger amount of sealant here until it squeezes out?
A few extra pics if they help...

The bath has a built in overflow channel and I noticed that water seemed to have collected inside the chamber after I'd let the water out. Is that normal?

If someone can give me a few pointers I'd appreciate it. Many thanks.
Lee

 

[Madrab]

Firstly - never use silicone adhesive on removeable parts like bath wastes. A little silicone sealant can be used if the mating surfaces are uneven or irregular. If it's all smooth then nothing is needed at all. The inner seal isn't really needed, the waste seals at the bottom/under seal. That needs a good fitting wide edged nut to ensure the seal is clamped nice and tight and flat against the underside of the bath. it'll never seal properly without it.
That slotted waste is slightly higher than the low point of the overflow channel I guess so some pooling would be expected.

Even with all of that though, it doesn't look like there's enough thread on the waste for a trap to be fitted properly.

It all just doesn't look quite right I'm afraid

 

[leescortxr3i]

Thanks for the feedback Rob. Yeah the thread isn't that big as you say. It actually came with an extension piece on originally (below). However this piece caused the bath trap to sit too low and was the incorrect thread in any case to fit into the trap - the diameter was too large and so just butted up with the trap thread rather than sitting within the female part and meeting the rubber seal. So I unscrewed this and it left the smaller thread that you can see above which is the right size for the trap. I was then intending on using a small extension from McAlpine as per the second photo below.

But yes ideally I think I need to have a waste fitting with a slightly longer thread.
Regards,
Lee

 

[Madrab]

That looks more like it, with the extended waste body. It comes down to being able to compress that seal properly and uniformly, so you could maybe use the adapter from McAlpine and use a hard flat plastic 11/2" thrust washer to allow the McAlpine extension to compress the seal properly.

 

[leescortxr3i]

That looks more like it, with the extended waste body. It comes down to being able to compress that seal properly and uniformly, so you could maybe use the adapter from McAlpine and use a hard flat plastic 11/2" thrust washer to allow the McAlpine extension to compress the seal properly.

Yeah thank you I'll see what I can do. I'm thinking of trying to use a 1.5' back nut to compress the lower seal and then see if I've enough thread left to get the mcalpine extension on (or even just the trap alone). The issue with using the extension piece to do the seal compressing is that I need to also ensure that the black rubber washer seal inside the extension meet the waste thread at the same time as compressing the rubber bath seal enough. So trying to do two jobs with it if you know what I mean. Will see how I get on.
So you don't think any sealant is necessary on the bath (plug hole) side?

 

[Madrab]

So you don't think any sealant is necessary on the bath (plug hole) side?

No - if you think about it, the only place the water can go from there is downwards by the outside of the waste shank/threads - as long as the waste nut, main seal and threads of the shank are all sealed, then the water can't go anywhere.

 

[leescortxr3i]

Hi all. Further to this I've now used the other part of the original waste extension after modifying it to accept the trap - had to grind off a lip on the end of it that was preventing the thread from meeting the rubber seal in the trap.
Closed the plug and filled the bath with a few inches of water and left overnight. I had a very small amount of water leak through the inside of the waste this time overnight. Not sure why that would be but is that acceptable? Thinking a bit more might leak through with a larger amount of water in the bath. At least it isn't leaking down the outside of the thread like before I suppose.

 

[Madrab]

That'll probably be passing around the plug itself, nothing unusual there with some of the new click clack type plugs.