Thanks very much judging by some of the responses I suppose what I should have asked instead is.
"For the Speedfit Tank Connector fitting to form a watertight seal do I need to make a hole exactly the diameter of the thread or do I get a few mm grace. The thread measures 36mm so does it seem likely that i'll be able to get away with a 38mm hole or do Speedfit connectors require more precision?"
From wiggikins answer it seems like it might work out ok?
If you need to find a tradesperson to get your job done, please try our local search below,
or if you are doing it yourself you can find suppliers local to you.
Select the supplier or trade you require, enter your location to begin your search.
Please select a service and enter a location to continue...
Are you a trade or supplier? You can create your listing free at DIYnot Local