I've been doing various adjustments and trials with my new chamber setup, which I'll pin up once I've settled on the final arrangement, and have configured circuitous venting in front of and behind my flow restriction. This has added many bits of additional plumbing to an already 'well-holed' set-up.
In total I now have 22 rubber seals [directly exposed to the chamber vacuum], it must be some 150-200 cm worth of rubber seal length! (Mostly buna, with a few viton)
The point of this post is to explain that I did not wet any of the seals. 'Common sense' tends to suggest one might want to add some sort of substance to aid the rubber-surface sealing, usually vac oil, and many suggest to do just that. However, as I was just experimenting and have not finalised a set-up, I did not bother to do so.
But it turns out that the chamber seems far better sealed than I might have expected. The pressure comes up so slowly from e-5's torr that I am getting bored waiting, when I want to run the next flow-rate test starting at a higher pressure! Maybe 1 micron in 5 mins, poss longer! I did not expect such good sealing from so many seals, and the difference to past installations is that all the seals have gone in bone dry, straight from an IPA wipe-over.
Does anyone else have any 'wet-versus-dry seals' anecdotes? I guess most go for CF-copper gaskets so may not have so much experience at the 'softer end' of kit build that I am at, but I would like to get a feel for whether mounting wet or dry seals have any other pros or cons people have identified that I've not thought of... Basically, once finalised, if I have to go back and refit them all, for a reason I've not yet thought of, there are so many that it might take hours!