Single axis drive for Celestron CG-5 mount

[chrisp9au]

Hi,

I'm looking for a single axis (RA) drive for a Celstron CG-5 mount.
I understand the gearing on my CG-4 motor is 1:11, whereas the CG-5 requires 1:15

Anybody got one sitting in a box in the shed? :)

Thanks :thumbsup:
Chris

[Ian Robinson]

I was told by Extravision, and by ScopeCity, and by people at CN too that the gear pitch on the CG5 is 144:1, mine takes 10 minutes to do one full rotation of the RA worm at 1x speed. Same rate as Vixen GPE, GPDX etc and EQ5.
EDIT (maybe the internal gearing of the CG5 and CG4 motors is different ?? , now I'm not sure , but I have been told the final output speed at 1x is the same ie 144:1==> 10 mins per full revolution of the worm).
See quote from an email I got from Celestron Support not so long ago that might help you :

I have also been told by Celestron that the single and dual axis stepper motor controllers for the CG5 and CG4 are interchangeable only the shapes of the motors are different.

May be able to help you out with a CG5 RA motor , I bought a couple of them not so long ago and was planning on upgrading an old Vixen Polar mount but haven't got around to it so the motors are stashed in the back of my steel locker in my garage.

I don't often log in here, so probably best if you email me , in the mean time I''ll see if I can locate that spare CG5 RA motor.
I've also got a CG4 dual axis drive box , that I don't need now (only got hold of it as backup) and I've now got two modified CG5 dual axis drive boxes (w/ autoguider port) so don't need it.

[chrisp9au]

Thanks Ian,

I have the CG-4 dual drives and controller, mounted on my CG-4 head. I've only just received the CG-5 head and, having not seen any stars for quite a while now, haven't been able to try it out.

My 'wanted' ad was really because 'googling' these drives indicates that the 95322 drives (CG-4) are 1:11 gearing, and the 95323 drives (CG-5) are 1:15.

To try my motors out, I will have to engineer a couple of mounting plates to fit the CG-5 mount, shouldn't be too hard I hope, and I do have time on my hands.

I'll get out in the shed tomorrow and see what I can do, then wait for a clearing in the clouds to see whether they track.

Thanks for the advice and the offer, I'll PM you and let you know how I go.

Cheers :thumbsup:
Chris

[Ian Robinson]

Easy to test (as per my PM).

Take off one of your motors, power it up via the drive and note how long it takes for the toothed gear on the mount drive shaft (external) to do one revolution at 1x drive rate, for the CG5 it should be 10 mins. ==> a wormwheel & gear ratio / pitch of 144:1

If it's different you need to get some extra gearing or do something to change the duty of the 1x rate power signal.

[chrisp9au]

Thanks Ian,

I'm advised, by folks on CN, that the CG-4 motor is geared with 132 teeth, the CG-5 is geared with 144 teeth, so they are not interchangeable.

I guess I will have to sell my CG-4 head with the motors included, and buy myself the CG-5 motors and handset.

Cheers :thumbsup:
Chris