Orpington Astronomical Society

Astronomy => Technical => Topic started by: RobertM on May 24, 2010, 09:08:24

Title: HEQ5 noisy bearings?
Post by: RobertM on May 24, 2010, 09:08:24
I have this problem (well not quite sure it is!) with an HEQ5.  When the mount is coming to a halt after a slew there is a noise which sounds suspiciously like very loose rattly bearings.  I can't quite work out where it's coming from but whilst slewing it is quiet; it also occurs to a much lesser extent when beginning a slew.  The motor gearboxes appear good and reduction gear mesh is sound.

Are these noises normal and if not has anyone come across them before?

Robert
Title: Re: HEQ5 noisy bearings?
Post by: Rocket Pooch on May 24, 2010, 09:13:06
Hi Rob,

Its the worm end adjustment again, my EQ6 does it all the time mine does not affect tracking. 

Chris
Title: Re: HEQ5 noisy bearings?
Post by: RobertM on May 24, 2010, 09:21:58
Thanks Chris, I'll check that tonight.
Title: Re: HEQ5 noisy bearings?
Post by: Tony G on May 24, 2010, 10:27:07
Robert,

My HEQ5 sound the same when starting or slewing on a fast rate, and it's been like that from new, with on problems in tracking or manoeuvring.

Wear eyeplugs like me, and all your troubles seem to fade away, and disappear.  ;)

Tony G
Title: Re: HEQ5 noisy bearings?
Post by: RobertM on May 24, 2010, 11:15:19
Thanks Tony, I did wonder about your eyesight but didn't want to offend.  For you I guess it's a case of see no evil hear no evil ;)

PS. Hope you don't drive with them in :o
Title: Re: HEQ5 noisy bearings?
Post by: RobertM on May 24, 2010, 22:49:46
The worm end adjustment is too stiff to move so it looks like a bit of a stripdown might be necessary.
Title: Re: HEQ5 noisy bearings?
Post by: Tony G on May 25, 2010, 10:32:29
Quote from: RobertM on May 24, 2010, 11:15:19
Thanks Tony, I did wonder about your eyesight but didn't want to offend.  For you I guess it's a case of see no evil hear no evil ;)

PS. Hope you don't drive with them in :o

Who said that?????????????? :o

Tony G
Title: Re: HEQ5 noisy bearings?
Post by: The Thing on May 21, 2011, 15:28:03
Quote from: RobertM on May 24, 2010, 09:08:24
I have this problem (well not quite sure it is!) with an HEQ5.  When the mount is coming to a halt after a slew there is a noise which sounds suspiciously like very loose rattly bearings.  I can't quite work out where it's coming from but whilst slewing it is quiet; it also occurs to a much lesser extent when beginning a slew.  The motor gearboxes appear good and reduction gear mesh is sound.

Are these noises normal and if not has anyone come across them before?

Robert

Hi Robert,

Now this mount is mine I took the cover plate off the cog housing to have look (as ya do) and lo and behold, a bolt fell out. The DEC motor plate was loose and this bolt had fallen out completely! I have rectified the situation and applied some nice boron grease then adjusted the worm. Much quieter! Some time soon I will do a complete strip down as there is still nasty rattle but only on the DEC axis. RA axis is very quiet.

Duncan
Title: Re: HEQ5 noisy bearings?
Post by: JohnP on May 22, 2011, 10:49:50
Robert - my eq6 makes same noise - again since new... TBH I have been using mine for about 4 years now with no probs. If I was you I wouldn't strip it may introduce other probs. Is this new or did you buy 2nd hand?
Title: Re: HEQ5 noisy bearings?
Post by: Carole on May 22, 2011, 10:54:55
My brand new NEQ6 makes a slightly metallic noise when it first starts slewing for 1 - 2 seconds, but then it disappears and it is fairly noiseless.

Carole
Title: Re: HEQ5 noisy bearings?
Post by: The Thing on May 22, 2011, 15:59:39
Hi John,

It's at least third hand since I have recently acquired it from Robert. I will strip it down as there is a glitch in the RA axis. It's nice and quiet but very tight, when I'm balancing the scope it doesn't move freely, it requires a shove. Also the giuding (been out the last three nights) jumps as if something is binding. It may just be the worm bolts and end float so I will try that first.

I adjusted the worm and end float on the DEC axis and it made a marked improvement to the noise (as did screwing the motor on!). The DEC axis also has a jump every few minutes so it looks periodic. I had a similar thing with my Meade fork mount and it turned out it was a tiny hard lump of grease on the worm. I suspect it all needs a good degrease and regrease.

Title: Re: HEQ5 noisy bearings?
Post by: Rocket Pooch on May 22, 2011, 16:13:35
Duncan,

The stiffness will not be the bearings but the brass bush the clutch goes onto, it might need 1,000th or so removed to make it move better.

Chris
Title: Re: HEQ5 noisy bearings?
Post by: RobertM on May 22, 2011, 19:21:16
Duncan,

I'm not sure you need to worry about it, the tracking was nearly perfect when I used it at DSC.  Not only that my new NEQ6 makes more noise than that HEQ5 and about the same as Fay's NEQ6.  The guys at FLO have said that's par for the course with these mounts and does not seem to affect performance.

Robert