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How many benefits you can count, plastic VS metal focuser for 60d refractor

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#1 Kiriakos_GR

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Posted 12 October 2019 - 06:27 AM

I am now having the awareness that my 60d refractor this seems as a small boat in the ocean when this aiming the sky or terrestrial targets.

Due lack of equatorial mount at default setup, and with only a slow-mo adjustment, I do find my self using the plastic focuser end as this be a steering wheel.

I do have a few shaking problems, and I think that the plastic focuser tube is to blame, because other telescope parts they are metallic (production 1994).    

Nowadays at the back of my head there is the thought buying a used identical telescope from the Japanese era which even the 0.965 inch focuser this is metallic.

 

And now here comes the question of how many benefits you can count at plastic VS metal focuser for 60d refractor?



#2 kurbs

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Posted 12 October 2019 - 06:34 AM

Plastic warps, expands, retracts, scratches, cracks, breaks. Metal is more stable, more consistent with grease, not prone to cracking breaking in pieces after a bit. However depending on the scope you may find the focuser to cost about the same as the OTA for a 60mm. There are folks here who sell them used for decent prices though.


Edited by kurbs, 12 October 2019 - 06:44 AM.

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#3 Kiriakos_GR

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Posted 12 October 2019 - 06:47 AM

At my side of the pond and regarding costs, I am able getting by spending about 45$ to get entire (used) 60-700mm telescope, so to remove the metallic focuser and transplant it at my own tube.


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#4 Littlegreenman

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Posted 12 October 2019 - 05:42 PM

Metal can rust or suffer corrosion. If you live near the ocean the salt water in the air speeds this up. Metal to metal contact can freeze up or bond together--if anyone knows the technical for this please speak up.

Over time it will re-crystalise and become brittle, although that usually takes decades to occur.

Metal vs. plastic also conducts electricity and may be magnetic, properties that would usually be irrelevant.

(But keep them away from Tesla coils and definitely MRI machines).



#5 Kiriakos_GR

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Posted 12 October 2019 - 06:20 PM

Metal can rust or suffer corrosion.

On that I assume that I will have to trust the research made by Japanese engineers, but thanks for the pointer, I can request additional pictures so to see the chromed pipe condition and it total length.   

 

While the plastic focuser from 1994 this is still undamaged, I think that a metal focuser made by finer teeth this it could possibly assist at more precise focus adjustment. 

 

My hidden fear this is that any upgrade to Plossl eyepieces , this it will increase the Yoyo motion at the plastic focuser due the increase of weight.


Edited by Kiriakos_GR, 12 October 2019 - 06:21 PM.



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