What's this connection called, and how do I fix it?

If you take the hot/cold disk off the top of the handle, you should find a hole where the screw/bolt goes into the spindle. Perhaps if you took the other tap apart, you would find what should be there and be able to match it.

Jonathan

find one then ...

Example taken at random so possibly not the correct size but the photo of the product shows the screw in the spindle

I think "splined" is the word you need.

I'd be tempted to introduce something into the gap. Even paper, card, or a bit of plastic bag might well make enough difference to help, at least for a while.

Chris

Surely there should be a screw in the 'handle' that engages with the ?threaded hole in the end of the spindle. I would expect the top of the handle to have a removable disc of some sort that will prize off with care, revealing the screw head. In your case that disc might be a classy bit of white porcelain labeled H.

Either that, or the screw has broken off and part of the threaded section is left embedded in the hole in the end of the spindle. Examine that hole to see if it's threaded.

Failing either of those, try araldite!

Even our cheap and nasty Screwfix ones have a cap with "Hot" or as it might be "Cold" on top. Unscrew this and observe a screw underneath, that screws into the top of the splined jobby.

It happens that WeeBob formulated :

Usually / always, there will be a screw which goes into the shaft to pull the handle on tight. The screw is then hidden by a removable cap. The shaft in the photo looks as if it may be drilled and tapped to accept the fixing screw.

Might the cap not be well glued on, hiding a screw?

Spline. As already said, use just the right thickness of paper to wedge it on fairly firmly. Plastic is more slippery so doesn't work as well, but it may do the job. The other option is silicone, put some in the socket before pushing it onto the spline. But acetic curing silicone does corrode brass and ruins brass plating, so use nonacetic.

NT

Thanks for all the useful replies.

uk.d-i-y is still be the best newsgroup on the planet!

I've got some that have what I'd describe as a spider washer in the top with a screw through it then the cap popped in over it. Brian

If the covers with the hot/cold logo are ceramic the cover may screw off. To unscrew try cripping with rubber cloves or an elastic band between the ceramic and your fingers.

Even when they're not glued on, the caps can sometimes be a pig to remove without damaging them.

not so much when the head has falleon off the shaft as a rod can push them from inside.

Soaking in descaler for a few ways should free any limed up threads too.

There is a hole in the centre of the splined shaft.

Is this threaded ?. If so it is the same as the standard taps fitted in the 70's, and in the centre of the tap head will be a decorative insert which can be carefully removed with a sharp knife or screwdriver.

Under this decorative cap you would normally find the brass machine screw and washer that holds the tap head onto the splined shaft.