What nut for a thermostatic shower valve?

[TonyR1]

I am fitting a thermostatic shower control. The flow knob fitting has a threaded section - 27mm OD - and it would be helpful to get a nut to go on it. Can anyone advise what I need and where to get it please?

 

[Ben-gee]

Don’t know, however this is not needed.

Why do you want to do it? Just out of interest.

 

[TonyR1]

Don’t know, however this is not needed.

Why do you want to do it? Just out of interest.

Just to add a bit of extra rigidity to the fixing

 

[ShaunCorbs]

3/4 inch nut / hex

 

[TonyR1]

3/4 inch nut / hex

Thanks. I tried one of those so it is 3/4 inch. The theads on the nut were too coarse though so it would only do a fraction of a turn before binding.

 

[Basher]

Just to add a bit of extra rigidity to the fixing

Wouldn't adding a screw to the fixing bracket in the pic help? Or is that piece of timber not fixed either!

 

[TonyR1]

Wouldn't adding a screw to the fixing bracket in the pic help? Or is that piece of timber not fixed either!

It is fixed by screws through those two tabs but there are only two which means it can still rock slightly up and down

 

[Ben-gee]

To stop rocking you just need to glue a shim/wedge at the appropriate location.

 

[TonyR1]

To stop rocking you just need to glue a shim/wedge at the appropriate location.

Easier said than done especially when you can easily spin a nut on the threaded shaft. A shim means trial and error trimming to the right thickness as its impossible to get in there to measure the gap. When I’ve got the right in-out position with the tiles in place I plan to foam behind it for insulation and to stabilise it. Looks like that is going to have to do as no-one seems to know what nut/thread it is.

 

[Ben-gee]

Nowt wrong with trial and error.
In reality with a box of assorted shims this task would be completed in less than a minute. Once the appropriate thickness is in there, a quick squeeze of silicone to hold the shim in place and leave it alone.

Honestly, you’re overthinking it - but that’s where experience comes in . At least you are striving to make a good job if it and I’m sure your final result will serve you well for the years to come, good luck.

 

[TonyR1]

Nowt wrong with trial and error.
In reality with a box of assorted shims this task would be completed in less than a minute. Once the appropriate thickness is in there, a quick squeeze of silicone to hold the shim in place and leave it alone.

Honestly, you’re overthinking it - but that’s where experience comes in . At least you are striving to make a good job if it and I’m sure your final result will serve you well for the years to come, good luck.

OTOH years of experience tells you also that if its threaded there should be a standard nut to fit it and secure it in place as intended - or perhaps the thread was machined in for decorative purposes 😉. A shim only works in one direction to stop the mixer block pivoting backwards. A couple of nuts work for both directions. Sorry its the engineer in me.

 

[Gasmk1]

How would the nut hold it and stop it moving, it may be 3/4 as stated but it is a fine thread, so you would need to find out what the thread type is contact manufacturer.

 

[Basher]

Sorry its the engineer in me.

Can you not exploit him to establish what thread It is?
Do you have a pair of verniers? If it is 3/4" the o/d should be 26.44mm. Could it actually be that?
Then mark off an inch and count the TPI (or measure the thread pitch directly)
3/4" should be 14 TPI, if not, what is it?
I just wondered if the thread binding you observed is due to a little damage somewhere, the above would confirm that's not the case.
If it's something different, time to exploit the interweb 🤔
eg: Thread Identification - Checkfluid - https://www.checkfluid.com/pages.php?pID=20&CDpath=3_20

 

[Ben-gee]

As I thought, you clearly have no skill/practical experience in this area.
This would be a complete non-issue to me that would be solved within minutes.
I don’t know how you use shims, but it obviously isn’t the way I do!