Screw thread help

[banjaxed]

I am trying to locate some longer screws to fit the Skymax 127 dovetail and finder brackets. They are 4mm in diameter but are not M4 thread. If anyone can enlighten me i would be very grateful.

Edited November 1, 2021 by banjaxed

[Laurieast]

The threaded holes in Skywatcher dovetail bars are camera tripod thread 1/4-20 UNC . Most consumer cameras are fitted with 1/4-20 UNC threads.

 

Edited November 1, 2021 by Laurieast

[banjaxed]

8 minutes ago, Laurieast said:

The threaded holes in Skywatcher dovetail bars are camera tripod thread 1/4-20 UNC . Most consumer cameras are fitted with 1/4-20 UNC threads.

 

Thank you very much for your reply. The screws i am looking for are the ones that actually attach the dovetail and/or finder bracket to the OTA. I think they could be 4mm fine thread.

[Carbon Brush]

From your description, I am guessing the OTA has captive nuts (sometimes called nutserts)

Given a sample of the screw, I am sure, like many on SGL,  I could identify the thread.

Hopefully a '127 owner who can identify the thread will be able to help.
It only takes a few minutes to remove and measure the screw.

Good luck with the search, David.