Jjust got some split rims of ebay (£20:00 )
Noticed one has bath sealer round the flange not sure if it actually leaks or not need to have it checked for a puncture first .
So my question is how are split rims normally sealed ? is there some sort of sealant or is it just a good machined finish ?

Usually some sort of sealant. Not usually tub sealer, good quality auto silicone is the way to go, a nice smear between the sealing surfaces should suffice.

AFAIK when you splt them it's good practise to replace all of the nuts & bolts with new.

Cheers, Ted

Many thanks
I was going to replace all the capheads and nylocs anyway tbh as there looking very shabby .