We have recently installed a pullout spray tap in the kitchen sink, and overall we are very pleased witrh the flexibilty it provides.
The only problem is that the retaining/securing nut works loose as the tap is swivelled left or right.
No matter how many times I tighten it, in a few days the tap works loose again and the whole unit becomes wobbly.
Either I have loaded the washers and nut in the wrong order, or there is something else.
The instructions say not to overtighten the large nut, presumably because it will distort the barrel's moving mechanism.The only other thing I have thought to do is place a piece of ply with a hole the dimension of the stem before the last washer and securing nut.
On the principal that the plywood would provide greater friction and prevent the nut from loosening...
A bit "Heath Robinson"ish I know, but what else do you suggest?