Any binoculor repairers here

[Davey-T]

Been sorting out unused stuff to give to a young lady school teacher that wants to get her class interested in astronomy when they eventually return to school.

Found a few old pairs of binoculars but this pair look to need collimating as see two of everything, stars that is, doesn't notice in daytime, also the view through them is very misty.

Can anybody versed in these things take them apart and see if they're salvageable please.

Dave

 

 

 

[DaveL59]

judging solely on the last pic they likely have prism tilt screws under the mismatched coloured circles (indicated)

Have you checked both objective tubes are tight and also square? Not uncommon for a slight knock to jump a thread and leave collimation out. Fairly simple to unscrew and refit, with care as the thread is quite fine and easy to cross thread.

Problem would be to achieve collimation rather than just an alignment for a specific IPD which would need proper gear which I don't have. No sign of fungus so likely just a bit of hazing which should be easy enough to clean up. Again though, once you pull the prisms to clean them you'd need to mess with getting them aligned or you're back to double vision. I doubt these will have eccentric rings in the objectives so should be simple to strip those out and clean both sides. Might be a simple clean of the occulars and objectives inside and out will be all it needs and perhaps the prism faces that are accessible when apart.

 

[Davey-T]

54 minutes ago, DaveL59 said:

judging solely on the last pic they likely have prism tilt screws under the mismatched coloured circles (indicated)

Thanks Dave, just have a feeling if I take them apart they'll end up in the bin 😁

Dave

[DaveL59]

Happy to give pointers on removing the occulars and so forth, it's not so hard if only doing minimal basics. Messing with the prisms tho can be, overdo it and you risk chipping them for example. Add in lots of patience to make small adjustment and check and repeat, can get frustrating. I guess the key things would be having the right tools tho like a small jewellers screwdriver for the locking grub screw in the hinge pivot screw, lens spanner to undo the rings holding the objectives etc. The trim/coating sections over the prism screws likely just prise off but may well be quite brittle but you might be lucky.

If you do unscrew the objective tubes, best to mark the relative position body vs tube and which side so you can refit to the same side and position as that can mess up the alignment also. You may even find that just removing them and swapping sides may get the alignment to be good enough 😉 

I'd offer but at the mo I'm supposed to be staying isolated and then of course won't be up to very much after 21-Jul for a few weeks, especially if messing about with someone else's gear...

[PeterW]

If you want to have a poke with a screwdriver have a go. I “fixed” an old pair Sam one prism had moved and reseating seemed to fix. To properly collimate (so it’s colimated at all IPD settings) needs special kit, give http://binocular-repair.co.uk a call, it’s not costly to recolimate.

 

petet