Panic at the disco, belt modding HEQ5

[Thalestris24]

Hi

Remember that you need perfect balance with the belt mod. East heavy in RA, or even a slight imbalance, will cause problems. You also need the belt tension just right...

Louise

[Anthonyexmouth]

Beyond a joke now. now stellarium scope disconnects as soon as it starts, PHD2 wont guide because it says the mount is slewing when its not. Can see this entire setup coming for a little trip on my boat tomorrow. 

[spillage]

Gremlins!!!!. I spent 3 hours chasing usb connections, changing leads and basically ripping everything apart. Next night all works as it should with the original leads.

[Thalestris24]

Sometimes you just need to power everything off and give it all a clean start. Also, you have to be methodical in this business!

Louise

[Anthonyexmouth]

Just as a test I swapped my 12v 5a PSU, that I checked and it's reading 12.4v , for a 15v 7a one I use for my model planes battery charger. Using that the handset worked first time. 

Any ideas folks?

[vlaiv]

Only thing that I can think of that would explain hand controller and PSU is that there is current leak in mount somewhere - maybe pinched wire or something. 5 Amp was not enough to maintain 12V and hand controller did not get enough voltage to run properly - 7Amp is just about enough.

Can you measure amperage being drawn from your PSU - or at least check if it's getting warmer than it should?

[Anthonyexmouth]

5 minutes ago, vlaiv said:

Only thing that I can think of that would explain hand controller and PSU is that there is current leak in mount somewhere - maybe pinched wire or something. 5 Amp was not enough to maintain 12V and hand controller did not get enough voltage to run properly - 7Amp is just about enough.

Can you measure amperage being drawn from your PSU - or at least check if it's getting warmer than it should?

Guess I could make up a little lead so I could run the power through my multimeter to check the draw. 

[Anthonyexmouth]

With both supplies it draws .09 during initialisation then settles at .3 but with the 12v one it errors and the 15v one initialises with no problems

[vlaiv]

2 minutes ago, Anthonyexmouth said:

With both supplies it draws .09 during initialisation then settles at .3 but with the 12v one it errors and the 15v one initialises with no problems

That is strange, but I'm guessing you will keep 15v for tests for now?

[Anthonyexmouth]

15 minutes ago, vlaiv said:

That is strange, but I'm guessing you will keep 15v for tests for now?

Yeah, I know 15v is on the limit but should be ok. I've got a spare 12v supply here for my aquarium in case the pump fails. As is usual for emergency kit, I can't find it. 

[Anthonyexmouth]

Just tried an old wall wart PSU 12v .5a and it fired up ok. Not sure it would slew but there must be some interference coming from the original PSU that's causing the handset to fail at communication with the mount

[vlaiv]

1 minute ago, Anthonyexmouth said:

Just tried an old wall wart PSU 12v .5a and it fired up ok. Not sure it would slew but there must be some interference coming from the original PSU that's causing the handset to fail at communication with the mount

I wonder if such interference can cause micro steps to "misfire"? Maybe it will help smooth out tracking / guiding (I would be surprised, but still ...)

[Anthonyexmouth]

14 minutes ago, vlaiv said:

I wonder if such interference can cause micro steps to "misfire"? Maybe it will help smooth out tracking / guiding (I would be surprised, but still ...)

The handset connection errors are all related to RA or Dec or both axis not responding so it's likely. I just put it down to a dodgy handset cable

[Thalestris24]

Hi

It's probably a good idea to use power supplies (switching ones) that have a ferrite choke on the low voltage side. You can get clip-ons quite cheaply:
https://www.amazon.co.uk/dp/B00V4PS6A6/ref=pe_3187911_185740111_TE_item

Having said that, I've used psu's that don't have a choke without problems but it's good practice to have one

Louise

[Anthonyexmouth]

It's actually got one, unless it's a dummy. Tweaked the RA axis, can't totally eliminate the tiny amount of play without it binding. 

[Thalestris24]

2 minutes ago, Anthonyexmouth said:

It's actually got one, unless it's a dummy. Tweaked the RA axis, can't totally eliminate the tiny amount of play without it binding. 

I'm sure it's good  It may be that binding gears is the source of your current problems. Astrobaby's guide to worm adjustment is very good but you have to follow it exactly. I think she says to only make tiny adjustments since the difference between binding and not binding is very small.

Louise

[Anthonyexmouth]

Just now, Thalestris24 said:

I'm sure it's good  It may be that binding gears is the source of your current problems. Astrobaby's guide to worm adjustment is very good but you have to follow it exactly. I think she says to only make tiny adjustments since the difference between binding and not binding is very small.

Louise

Yeah, i think I got the RA wiggle to at least as good as it was before I started tinkering, maybe a bit better. Forecast Is low cloud tonight but if it clears I'll try with this other PSU. If it's better I'll consider binning £100 and doing a teardown, bearing change and regrease

[Thalestris24]

17 minutes ago, Anthonyexmouth said:

Yeah, i think I got the RA wiggle to at least as good as it was before I started tinkering, maybe a bit better. Forecast Is low cloud tonight but if it clears I'll try with this other PSU. If it's better I'll consider binning £100 and doing a teardown, bearing change and regrease

If it's not particularly old and previously had no signs of wear I wouldn't have thought it was worth it. My heq5 is 5 years old and is fine - I belt-modded it 4 years ago. I've previously given it a stripdown and regrease but have never contemplated changing bearings.

Louise

[Anthonyexmouth]

1 minute ago, Thalestris24 said:

If it's not particularly old and previously had no signs of wear I wouldn't have thought it was worth it. My heq5 is 5 years old and is fine - I belt-modded it 4 years ago. I've previously given it a stripdown and regrease but have never contemplated changing bearings.

Louise

did the regrease make any difference? i was just wondering if quality bearings might make the rebuild and tuning easier. 

[spillage]

I would say the worm shaft bearings maybe be worth changing but if the main bearing look okay with no corrosion then they should be fine with just a clean and regrease.

[Anthonyexmouth]

1 minute ago, spillage said:

I would say the worm shaft bearings maybe be worth changing but if the main bearing look okay with no corrosion then they should be fine with just a clean and regrease.

its only about 8 months old, but read a few stories where bearings were rough from the factory. maybe i'll get some good quality worm bearings and start there. 

[Thalestris24]

59 minutes ago, Anthonyexmouth said:

did the regrease make any difference? i was just wondering if quality bearings might make the rebuild and tuning easier. 

I'd like to think so! Though, in truth, I think the belt mod made the biggest difference and improved guiding considerably. It's quite a bit of work to do a strip-down and opens the possibility of something going wrong. Um - if it ain't broke etc. It's worth bearing in mind that the RA axis only goes one way so there is less demand placed on it.

Louise

[johnturley]

I was planning to get an HEQ5 mount for my ES 127 Refractor when I finallly get my Esprit 150 (which will be mounted piggyback on my 14in Newtonian in place of my ES127), to give me a more portable instrument than my CPC 9.25 (which isn't that portable). I was though a bit undecided whether to order the mount with the Rowan Belt modification, however what I have read on this thread has put me off this belt modication, and made me suspect that it might be more trouble than its worth, especially as the ES 127 would only be used occasionally, such as when the view from my observatory shed is blocked by trees.

John

[Anthonyexmouth]

20 minutes ago, johnturley said:

I was planning to get an HEQ5 mount for my ES 127 Refractor when I finallly get my Esprit 150 (which will be mounted piggyback on my 14in Newtonian in place of my ES127), but was a bit undecided whether to order the mount with the Rowan Belt modification. However what I have read on this thread has put me off this belt modication, and made me suspect that it might be more trouble than its worth, especially as the ES 127 would only be used occasionally, such as when the view from my observatory shed is blocked by trees.

John

The belt mod hasn't been my issue. Looks like dirty power has had me tinkering where I shouldn't have been and chasing problems that weren't there. It's so much quieter with the belt mod. 

That's not too say the whole lot won't end up at the bottom of the sea if I don't correct the problem. I'm very much an outlier as far as modding the heq5 goes, the procedure is dead easy. 

[JamesF]

I believe there's a general consensus that these mounts are happier when fed on something closer to 13.8V rather than 12V.  The PSU's I have for mine are 13.8V regulated, rated for 5A continuous.

James