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Heq5 Pro adjusting

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#1 hanva

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Posted 19 March 2018 - 03:11 PM

I'am sorry my poor English. I need to use Google translator now and then but I hope that you will understand me.

 

I would like to ask if there is any experience how small the backlash of that mount can be obtained? I drove the guide assistant in PHD and it suggested dec-axis backlash compensation 2400ms. It would seem like a little big in my own mind. I have adjusted the pressure of both the axis upon a worm screw in such a way that the play in its movement does not seem like much, but the cogwheels rotate with your fingers.

 

Then I'm thinking of rotating the axles when the locks are open. How slick should the axles rotate and whether it is relevant to tracking accuracy? In my own mount, the RA axle rotating more slick than the DEC axle, but there is also a certain point when the motion will stick to the hint. The Dec axis makes the movement more sticky all the way and there are also points where is more stick. This is when I rotate the axles without load. When the load is on, the axles seem to be moving more slick.



#2 leveye

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Posted 19 March 2018 - 03:26 PM

Some of this may help...

 

http://www.astro-bab...ld/heq5-we1.htm



#3 sg6

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Posted 19 March 2018 - 05:24 PM

My HEQ5 I ended up pulling apart - it was sticking at too many positions.

I found that the original grease had been removed and replaced but it seems that the person just hadn't put it back together carefully enough. Bearings and aligments were wrong, think one bearing was incorrectly inserted so at a slight angle.

 

A little care and doing things "better" and the mount is now fairly smooth in both RA and Dec - you could find that Dec is the standard problem area. Although smooth mine could be better.

 

Probably the simplest improvment came from setting the motor gear and the driven gear of the worm "right". I found that the motor gear had to be about 1/2mm lower then the worm gear, if the 2 were on a level then it would stick. Getting the mesh was simply trial and error. Fairly obvious too tightly meshed then it stuck, too loose and it was not smooth.

 

The other area was the setting up of the grub scerws where the rod for the weights exit. That was another area where it seemed easy to cause slight distortion and so the Dec axis would stick as it rotated. If you get that far be careful of those grubscrews, easy to lose and a pain to get back in the correct place. Took me about 4 attempts.

 

Astro Baby's guide is a good one, although the one I had was for a strip down and rebuild which may be more then you anticipate. I sort of pulled half (Dec) of mine apart.

 

When you get into the mount you realise that people at the factory assembly stage are not going to carefully set it all up and double check things. They likely are expected to do 4, 5, 6 or more a day. If you want a really smooth running one then some knowledge and a few days are required. And several plastic tubs for the assorted bits.


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#4 frito

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Posted 19 March 2018 - 09:57 PM

sq6 is spot on, i've done both the RA and DEC on mine its a bit tricky esp the DEC for some reason but well worth taking the time to teardown clean and adjust it all if its an old unit and performing poorly. they are fairly easy mounts to work on overall though main thing is watch out for set screws, use the astrobaby guide as a reference. there are multiple places where threaded things are held in place by set screws and if something gets hard to unthread theres likely a set screw not back out enough in the way as the cause and if you force anything you will mess up the threads if its a set screw causing it. 



#5 hanva

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Posted 20 March 2018 - 11:53 PM

Thank you for the information.


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