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Repairing a RA fault

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#1 MikeMS


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Posted 13 June 2013 - 12:09 AM

I have just repaired a new ETX for a local school. Whilst still with the tissue over the OTA the plastic ring that holds the gearbox to the shaft on the RA worm has snapped. I glued it back together and glued some string around it to spread the load.
I have some spares from a previous repair and the older ETX had blue plastic for the gearbox casing and this new one black. Not interesting, but the blue plastic looks a bit thicker around this part and less prone to snap. Now, the older part is better made and survives longer. As this is an internal part, human activity is not a factor on its life. I had the same on two motor bikes, 10 years apart and the same model, the older dust caps lasted longer than the new ones, in front of me I had 14 year old dust caps good as new and 4 year old ones splitting. It is as if failure is being put into newer versions.
Kind regards,

#2 *skyguy*



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Posted 13 June 2013 - 11:21 AM

The CN ETX-125 review includes a photo that shows the plastic ring that holds the gearbox shaft to the RA worm. It also shows a broken mounting bracket for the gear box. Another common problem!

ETX-125 Review

Great information on repairing the ETX. It does seem the older models on most products ... including telescopes ... are built better and last longer. Not always the case ... but, often true! :(

#3 Geo.



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Posted 18 June 2013 - 07:09 PM

It's a common failure. I don't think there's any difference in the gear boxes other than the color. If I was desperate for the part it look like something could be done with some aluminum and a ball bearing. I just set my last spare off to Cyprus! Here's a Alt motor getting a real bearing before being asked to do some heavy liffting.

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