9 replies to this topic

[andrewpugh]

Hi group!

 

A Summer 2022 I aquired my Celestron 9.25 edge and some related hardware.

All new equipment.

The first night (august? september?)  I put on the celestron 0.7x reducer and took some photos of the moon.

At the end of the session, I was unable to remove the 0.7x reducer from the scope manually.

It was STUCK tight!

I did not torque it down when I screwed it on. Just hand tight.

I managed to get it off but it took some inventive use of plumbing tools and some rubber sheet.

I then applied a thin coat of either a thin liquid silicon lube, or thin coat of a thicker grease. I do not recall.

 

Testing the removal of the reducer afterwards, it seemed to help.

 

October 2022, I intalled the reducer again. This time recalling the effort to remove it,  I was cautious not to over tighten.

It was firm enough to hold camera without any play.

I did not apply any lube, as I had already applied a very thin coat the last time which I thought would be sufficient.

 

At the end of the session... yep,... it was stuck.

In fact it seemed to be tighter than the last time. It seemed to take way more swearing than the last time to get it off using the tools/rubber sheet technique I had used in the past.

The teeth of the pipe wrench cut through the rubber several times during my efforts.

I am fortunate not to have scratched or damaged the reducer.

 

Questions:  What sort of lube is safe to use on screw on optics?

I have heard stories of vapor outgassing issues of certain scopes, that cloud the mirror/optics with a haze.

I do not want a thin layer of hydrocarbons or such building up on my glass/mirrors.

 

How common is this problem? I am aware of one other person who has warned of this.

 

Before posting this I thought that MAYBE applying some heat (hair dryer or such)  to warm up the reducer might have helped.

Does anyone know if this would in fact help? Or make things worse?

 

Thanks for feedback

 

Andy

 

 

 

 

 

 

Edited by andrewpugh, 03 December 2022 - 12:23 PM.

[doole]

I'd try to find a way to test the thread on the Edge for abnormalities and if it works well with other attachments I might just lose the reducer. In any case, I don't think I'd use it again until I knew. (I would normally always coat a new thread with a thin layer of vaseline, assuming I can keep the stuff well away from glass. Haven't had any mishaps related to that.) -chris

[t-ara-fan]

Pipe wrench?!?!?!?!?!!!

Get a strap wrench.

[andrewpugh]

Strap wrench!  Good idea, I will look into that!

[CharLakeAstro]

You might want to look into having the internal threads of your reducer chased. There might be some anodizing in the threads. I have the machine tools here to do it myself, but if you don't, then find someone reputable to do it for you. Gunsmiths usually work to tight tolerances and likely have familiarity with optics also.

 

As for lube, light application of candle wax works well.

[andrewpugh]

Candle wax.. another great idea!

Thanks

 

[andrewpugh]

Strap wrench!  Good idea, I will look into that!

I should mention... I used rubber sheet between the pipewrench teeth and the reducer!!!

[MJB87]

Strap wrench!  Good idea, I will look into that!

A pair of strap wrenches was one of the smartest astronomy purchases I ever made. Can't tell you how many times I have relied upon them. Highly recommended

[t-ara-fan]

A pair of strap wrenches was one of the smartest astronomy purchases I ever made. 

I got some of these too. Ideal for removing a 2mm long male-male adapter. It is too short for the strap to bite on.

 

https://www.amazon.c...duct/B018I84358

[PatrickVt]

It is quite likely that the pipe wrench was actually compressing the sides of the reducer as you attempted to unscrew it.  Compressing the sides (or warping the circular form of the reducer) will add even more friction to the mating threads.  This happens quite often with all sorts of threaded adapters.  

 

The solution (most times) is to use the lightest of pressure on the sides of the parts you are trying to disassemble.  Sometimes, applying the rubber sheet to the end of the reducer, pressing inward toward the scope for friction, applying no pressure to the sides, then turning works.  Sometimes just lightly grabbing the exposed edge between thumb and forefinger to turn it lightly will work.  But applying a lot of pressure to the side will usually only add to the friction between the two parts because it deforms the circular shape of the threaded parts.  

 

Of course, now that you have used a pipe wrench on the reducer, it could be permanently deformed and will always be difficult to unscrew.

 

Patrick