Holesaw size for 2 1/4" immersion element ?

[Andy]

Hi,

I need to cut a hole to accept a standard 2 1/4" immersion element thread and am looking to use a holesaw to cut the hole. Anyone know which size holesaw I should use ?

Plumbworld seems to think a 66mm saw :-

this correct ?

Thanks,

Andy.

[Bob Minchin]

I've got a new flange washer here and it is 65mm bore. No idea it it would be a tight fit or a slip fit but looks ike you would not go wrong with a 66mm saw.

hth

Bob

[Roger Mills]

Assuming the thread is 2 1/4" BSP, the *actual* thread OD is 2.587" which is

65.7mm - so it should just about go through a 66mm hole - but there ain't a lot of clearance.