HEQ5 standard ratio 9:47 belt mod.

[malc-c]

Doesn't that sound sweet without that normal graunching sound on spool up and down

Nice work Dave

[Fred_76]

Nice work !

I dont think adding an idler is a good idea. You need to ensure constant speed to the belt, not a constant tension.

In the case there is a little resistance on the 47T pulley coming from the worm, the idler will release some micrometers to the belt and it will add an error to the guiding speed...

[1parsec]

Thanks Malcolm and Fred. It's coming together quite well now.

I took more tracking logs using the belt drive and I very happy with the improvment in the PE and the lack of 'graunching"

Fred. The idler is just a 'cotton reel' shaped spool in a fixed position and doesn't move like a normal tensioning idler.

It modifies the belt path to allow a full 180 degree wrap around the smal pulley which I think is worth investigating.

Another track log for comparison will be needed to confirm or reject this idea. The concentricity of the idler is very good and

it should not induce an variation in belt tension / speed. If there's no negative effect I'll leave it in.

Dave.

[malc-c]

That does look good....and is a neat way of getting more of the belt around the pulley. It would be interesting to see if it makes any difference to the PE or tracking.

I've just used PHDLab to Analise one of the original log files I did after doing the conversion - seems that by improving the the PE performance and providing a tighter drive train the guiding also becomes more precise

[1parsec]

That does look good....and is a neat way of getting more of the belt around the pulley. It would be interesting to see if it makes any difference to the PE or tracking.

I've just used PHDLab to Analise one of the original log files I did after doing the conversion - seems that by improving the the PE performance and providing a tighter drive train the guiding also becomes more precise

Hi Malcolm, I haven't any guiding history for my mount when it had the gear train, but the reduced PE / backlash with the belts will surely improve guiding too. Dave.

[1parsec]

These clear nights are really helping with the belt mod upgrades ready for darker nights The idler hasn't had any negative effect on PE but still has its benefits Without the idler the direct belt path meant the motor was very close to the casting (I had to trim a bit off the motor) and no idler makes fitting the belt over the pulleys difficult. With it fitted it makes it easier to get the belts on and get the motor to be in the middle of the adjustment slots. PecPrep screen grabs of the belt drive with and without idler - Dave. (Sorry for this being all in line - Carriage return not working )

[Freff]

It may be your browser if you are using Explorer 10 messing with the return carriage. Try using the mode toggle button. HTH

[1parsec]

I'm working on the spacer for the cover and just to give it a final check for size, plotted the profile 1:1 on card.

All holes and sides aligned with the mount ok. The intention is to get the spacers laser cut in white acrylic.

Dave.

[Teslar]

Any progress on the cover ? I'm very interested in this mod

[1parsec]

Any progress on the cover ? I'm very interested in this mod

Hi Teslar, I've been on holiday for the last couple of weeks but should have some progress to report with the spacer / cover in a few days.

Dave.

[1parsec]

Phew ! The spacer fits to the mount and aligns with the cover very well.

I'm glad I went for the white acrylic as it matches the mount and blends in really nicely.

Dave.

[Teslar]

Neat job there it looks perfect

[malc-c]

Very neat...

[JamesF]

Indeed it is. You barely notice it's there.

James

[1parsec]

Thanks Telstar, Malcolm and James.

Dave.

[kookoo_gr]

Very nive mod. Since it interests me how well does it behave during astrophotography, asuming you have tested it. If it works better that the stock gears is it possible to place some kind of an order for an extra?

[Teslar]

I'd be interested too if you plan to supply Kits for this mod

[1parsec]

Very nive mod. Since it interests me how well does it behave during astrophotography, asuming you have tested it. If it works better that the stock gears is it possible to place some kind of an order for an extra?

Hello Kookoo,

The tracking of my was improved on my mount.

The previous posts up the thread show the Pecprep data with before and after curves.

And it's so much quieter too

I am making more kits, but forum rules mean I can't advertise here .

Dave.

[Teslar]

I've fitted this mod to my HEQ5 and I'm well impressed with the kit and the difference it's made to my mount. Much quieter and smoother. Not had the chance to do any plots yet but no reason to suspect I won't see the improvements that others have. I posted a video on YouTube but not sure if I can link it here. If anyone wants to see it PM me

[malc-c]

I'm sure its fine to include a link to the video, and I'm sure people would like to see this in action

[Teslar]

I did post it in suppliers reviews but it's not been approved yet so I though there might be a problem with the admin team. I'll check there first and see if there's a problem

[gary1968]

That is a very neat, professional soution to a long standing problem with these otherwise great mounts....... I would be very interested in buying a kit if you are considering kitting it.

Gaz

[JamesF]

That is a very neat, professional soution to a long standing problem with these otherwise great mounts....... I would be very interested in buying a kit if you are considering kitting it.

You can buy (most of) the parts as a kit here: http://www.beltingonline.com/heq5-belt-mod-drive-kit-12097

You just need to get the spacer made up one way or another. if and when I get to the point of doing the upgrade and if no-one else beats me to it I will try to remember to make up a PDF of the spacer design for others to use.

James

[gary1968]

thanks for the link James, however I am interested only in the conversion if it preserves the standard ratio as I will want to use the handset as well as eqmod.

Gaz

[JamesF]

Ah, you're right. Sorry. I was getting confused. I'm still suffering from lack of sleep at the start of the week. Can you tell?

James