I have just bought a complete set of Bobs Knobs (Primary Knobs, Locking Knobs, Springs and Secondary Knobs) for my GSO 12". Followed advice on the Bobs Knobs website that recomended ordering parts for Meade 12" lightbridge as they use the same threads. Primary Knobs and springs are fine but when I tried fitting the Secondary knobs they are clearly a different thread. Anyone else had this problem and is there a solution?
Malcolm,
Once you've made sure that your assumption is correct, I would contact Bob's Knobs and let them know of your problem.
If someone close to you has carried out this mod, see if you can check out their secondary knobs.
Good Luck.
I bought a full set for my GSO 12" last week from Bintel in Sydney. When I asked for them, Don asked if my scope originally had any knobs or just screws. It seems there are two different thread sizes on these scopes over the years.
When installing the secondary knobs, they felt like they were the correct thread, but were very tight, but once I put some (very little) silicone grease on the threads, they went in like the proverbial rat up a drainpipe.
