I'm a great believer in not stripping down unless neccesary,too.
I have many medium format folders & my favourite are the Zeiss Ikon ones, such as the Nettar, because they almost always work well with nothing at all done to them (unlike Agfas, which always need the bellows repairing or replacing or Voigtlanders which usually need the leatherette gluing back on...:rolleyes
You may find the slow speeds will work after the shutter has been fired a few dozen times - if not, does it matter?
I certainly would clean the lens. Get the dust off with a soft brush first (so as not to scratch it), clean it wet with plenty of pure ethanol with a CLEAN lens cloth or lens tissue. If mucky inside, remove the front bezel (tiny screws) and then unscrew the front element. Ditto the rear element, ONLY if neccesary.
I have a slight difference of opinion about "Collimation". I won't claim to be an expert on such things, but I humbly submit that this word is sometimes misused in this context on APUG. If you strip a lens right down to it's components (take all the seperate glass lenses out of their mounts) then you will need to re-collimate the lens. This means alining each element so it's axis is perfectly centred on, and parrallel to, the optical axis of the lens. You will need an optical bench, a laser and special tools. Assuming you don't have them to hand... NEVER, EVER, EVER strip a lens down this far - a most folding cameras would never be worth enough to justify this being done professionally, either.
With a simple lens it is not neccesary. You can unscrew the brass front and rear mounts, clean them, screw them back in and all will be well (just be careful not to cross thread them!)
What you
do need to do is reset the infinity focus - which I suspect is what some people mean when they say collimate...?
To do this you need a peice of ground glass to place in the film gate (you can improvise with tracing paper stuck to clear glass or with frosted plastic, or matt varnish on glass etc.) With the lens wide open, camera on tripod, dark room, focus on a bright lamp at a carefully measured 20 feet or so (not critical, but too near and the depth of focus at the film plane is too great - everything looks sharp). Get it as sharp as you can. Now rotate the outer bezel to 20ft without moving the lens and tighten up the screws. Check it at 10ft and then take it outside (with a cloth to go over your head) and focus on the moon or a very distant tree or something to check infinity. Once you got your ground glass organised this is a 5 minute job. I've checked all my folders like this and sometimes it is all you need to do to transform a 'lemon' with a suspected poor lens into a great, sharp shooting, precision instrument
