26 Aug
2006
26 Aug
'06
3:34 p.m.
Do mechanical adding machines / calculators favour any particular kind of oil
(or grease) - or is it just a case of going for the lightest stuff possible?
I've got one here (adding machine - Bell Punch 509) that's in remarkably good
condition, but some of the mechanism needs a little 'help' for it to work. I
don't think it's binding due to any mechanical distortion (although it could
well be simple wear) - chances are that whatever lubricant was used has long
since given up though and sorting that out may well get it going again.
You're not going to want to hear this, but...
Old lubricant does 'turn to glue' and cause things to stick. And adding
more lubricant won't really help, you need to clean off the old first.
Now I've been flamed for this before, but any _real_ clock repairer will
tell you the only way to do this is to take the thing apart and clean the
parts in a suitable solvent. And then put it back together with the right
lubricants.
As regacds what lubricant to use, I use 3 :
High melthing point grease (normal car grease, Castrol LM, etc) on very
slow moving parts like the carriage slideways and the handle gearing
Clock oil (obtained from a watch/clockmaker's supplier) on most parts.
Watch oil (a thinner version of that) on small, fast-moving parts. Not so
much on calculating machines, actually, but it's what I'd use on the
bearings of a camera shutter timer [1].
[1] As to what I'd use on the gear teeth in that mechanism, I wouldn't.
They are designed to run dry. Maybe 1 drop of watch oil on the 'scape
wheel and pallets.
-tony