bath lead to plastic joint how?

Look for leadloc or leadlock. You'll need to measure the size of the lead pipe. Or a "universal" fitting.

Presumably you are talking about the drain, not the water supply.

Depends on the mechanical detail of the joint. Silicone would usually be better.

For a waste pipe, self amalgamating tape might do the job.

If you can stretch it to twice its length whilst wrapping it around the pipe.

The shopping channel QVC used to sell a meter length of this tape for mega money. The sales pitch showed a demo where someone repaired a leak in a live supply pipe. The pipe was suspended in the middle of a large glass tank allowing the person demonstrating the tape to stretch it with ease. The reviews on the product were not to good as in the real world most water pipes are clipped to a wall with a fraction of an inch clearance and often in relatively inaccessible places making stretching of the tape whilst winding it around the pipe near impossible :) Not too good when trying to repair an emergency leak which the sales blurb claimed was the ideal application :)

How to use the tape

In message snipped-for-privacy@googlegroups.com, "George Miles (dicegeorge)" snipped-for-privacy@gmail.com writes

I had one in the utility room from the washing machine to the lead drain of a Belfast sink. I stuck the plastic pipe inside. I filled the gap with Plumber's Mate as a temporary fix about 25 years ago. I found a rubber boot flexible adapter a couple of years ago that fitted both nicely and finished the job off.

Bit like these.

Brian

Yes this happens as if the flow rate is quite slow, and the height of the water in the bath is higher than the join, its going to be one heck of a job to fix it. I guess there is no way to get a pipe straight onto the plug hole? I guess its either sweated and soldered or completely solid and might damage the bath if brute force were used. Brian