Need help identifying Counterweight shaft stop to buy


Howard Hedlund
 
Edited

For testing, try a knob from a counterweight.  It should also have  5/16"-18  threads.
You may want to have someone with a 5/16"-18 tap chase the threads in the shaft.


M Hambrick
 

Actually, they do still sell these. The price is a little higher now. You might need to keep the large washer that you used for the stop on your 1.875-inch shaft.


M Hambrick
 

Hi again George

It might be worth checking with Astro-Physics to see if they still have any of the machined safety stop knobs that fit the old counterweight shafts that used the 5/16-18 thread for the stop. The catalog number was MSSKB.

I bought one of these in late 2016 to use on my old 800 mount. The cost was $27.00. As with all things Astro-Physics, the quality is excellent, and the machined aluminum is much more durable than the phenolic knobs.

Mike


Dan Folz
 

I can confirm that the bolt size is 5/16-18. I recently replaced a broken phenolic knob with whats shown below.
Hope this helps!

Dan

On Friday, April 29, 2022, 05:24:25 AM CDT, M Hambrick <mhambrick563@...> wrote:


I believe that the threads on the stop are 5/16-18, but someone from A-P can confirm this. Do you have a bolt with the same threads that you can try in the shaft ?

Mike


Howard Ritter
 

Or take the shaft to Home Depot and try either their thread template or bolts from the specialty cabinet. I’ve found that strategy very useful!

—howard

On Apr 29, 2022, at 6:24 AM, M Hambrick <mhambrick563@...> wrote:

I believe that the threads on the stop are 5/16-18, but someone from A-P can confirm this. Do you have a bolt with the same threads that you can try in the shaft ?

Mike


M Hambrick
 

I believe that the threads on the stop are 5/16-18, but someone from A-P can confirm this. Do you have a bolt with the same threads that you can try in the shaft ?

Mike


George Lutch
 

I'm trying to identify what counterweight shaft stop I need to purchase as a replacement.  It is on an AP900GTO from 2005.  The shaft is 1.875 in diameter but the stop that is supposed to fit it does not.  Any assistance would be greatly appreciated.