[Amps] HV clearance? and feed thru Capacitors

[Neil Carr G0JHC]

There is a common 680pf "6kv" HV feed thru Capacitor on the market, that
many seem to use, manufactured by Sprague,  seen here
http://www.rfparts.com/caps2.html#high

 

I was just about to put one of these in my latest project to get 5kv through
the RF chassis wall, but became nervous at the clearance, which is 4mm from
HV pin to locking nut.

 

Pleas give me your opinion on this item. I have designed a min of 25-30mm
(2"+) elsewhere.

 

Does anyone run this device at 5kv or above and  had problems?  

 

Thanks for your time.

 

Neil G0JHC