Stripped threads on EFW...

KenV

I was changing around my imaging rig after getting the new OAG-L for my ASI2600, and unfortunately tried using the ZWO-provided screwdriver instead of my own. This has a regular handle on it (my own has no handle---you grip the body which is about as wide as a regular screwdriver's shaft). The problem came from the greater torque I had, and I believe I stripped the threads on one of the small bolt positions on the EFW wheel; I mean one of the three very small screws inside which hold the wheel to the shaft.
I backed off the screw and gently re-tightened to where it felt somewhat snug since I hope to use it in two weeks. But something definitely went south. I do not know if it was the screw threads or the threads in the metal it tightens into.
What should be done at this point? My local shop has no parts for this and recommended that I speak with ZWO.

Has anyone else done this, and what was the resolution (if any)??

Thanks!

Kenward

Tech@ZWO

Hello,
Can you attach some related photos here?
It is very hard to understand through words.

w7ay

@tech@zwo#49339 Can you attach some related photos here?
It is very hard to understand through words.

He needs the three screws that hold the carousel (the big round plate that hold the filters) to the center bearing.

Stainless steel, Flat head, M2 x 2.5mm long, cross head.

Chen

KenV

Chen is correct in the description. I guess I need to take the wheel apart again, since I do not know if the bolt threads are stripped or if it is the threads in the hole of the plate they screw into. Has this happened before, and if so which part gets damaged?

w7ay

KenV if so which part gets damaged?

Aluminum vs Stainless Steel; my bet is stainless steel won.

With small threads that don't have that much surface area, you need to be careful how much force to apply. Smaller the screw, smaller the threads, thus smaller the force. For anything smaller than an M3, I would not tighten the driver more than by using one finger and a thumb, and use a driver with a small handle to further reduce the torque.

Chen

KenV

I'm sure you're right! 🙂 I didn't know from what the underlying disk was made.
I removed the carousel again and examined the holes and bolts. It's very hard to make any good statement about it though. I was at least able to snug down the bolts again using my own, skinny screwdriver. One did feel "soft" at the end.

What would be a way to address this if it later gives way totally? Would using an M2.5 to enlarge and re-thread the hole be possible? Or is a longer M2 possible (does the threaded hole extend further through the disk, allowing one to use a longer bolt)?

Thank you for this information!