HEQ5 Rowan belt mod problem - only one grub screw on gear on motor

[athornett]

Hi All

Can someone offer advice?

I started process of HEQ5 Rowan belt mod this morning only to find that both RA and Dec motors on my HEQ5 Pro only have ONE grub screw on gear axis rather than two as stated on the mod instructions. I have loosened the one grub screw but the gear will not pull out - according to instructions it should now slide out easily but it won't budge a mm!

What do I do?

Andy

[athornett]

I have received this reply from Rowan Astronomy which explains the problem I am experiencing:

Hello Andrew,
 
Thank you for your e-mail.,
 
From your description I think you have an older HEQ5 mount.  These mounts have the transfer gear mounted on a shaft with a hex head. This photo shows the type.
http://rowanastronomy.com/lphoto5.htm
 
Once the grub screw is loosened the shaft has to be unscrewed from the motor plate.
 
The hole in the motor the plate is threaded and there are 2 options to fit the idler roller shaft.
a. Cut the idler roller shaft with a dremel or grinder and then epoxy the idler shaft in position.
b. Drill the motor plate through with a 5.0mm drill to remove the thread.  I recommend this is done on a drill press and not ‘free hand with a pistol drill to ensure the hole is drilled square to the plate. The idler roller shaft is then fixed in position with the side locking grub screw.
 
Kind regards,
Dave Rose

Rowan Engineering Ltd
www.rowanengineering.com

[smashing]

38 minutes ago, athornett said:

I have received this reply from Rowan Astronomy which explains the problem I am experiencing:

Hello Andrew,
 
Thank you for your e-mail.,
 
From your description I think you have an older HEQ5 mount.  These mounts have the transfer gear mounted on a shaft with a hex head. This photo shows the type.
http://rowanastronomy.com/lphoto5.htm
 
Once the grub screw is loosened the shaft has to be unscrewed from the motor plate.
 
The hole in the motor the plate is threaded and there are 2 options to fit the idler roller shaft.
a. Cut the idler roller shaft with a dremel or grinder and then epoxy the idler shaft in position.
b. Drill the motor plate through with a 5.0mm drill to remove the thread.  I recommend this is done on a drill press and not ‘free hand with a pistol drill to ensure the hole is drilled square to the plate. The idler roller shaft is then fixed in position with the side locking grub screw.
 
Kind regards,
Dave Rose

Rowan Engineering Ltd
www.rowanengineering.com

Wow, a timely post as I've just finished the mod to my old HEQ5 this morning remove the grub screw and use a spanner to undo the hex bolt (it will take a bit of effort)

I opted to drill out the plate with a 5mm drill bit and tbh i have worried about it for a long time and it was actually fine.

I find it odd that they are saying to use the grub screw to secure as the heights on mine wouldn't have made that workable and used a little epoxy to secure it in 

Edited April 10, 2021 by smashing

[Penguin]

And it looks like I have the same issue. already had to fashion my own DIY spindle puller as I forgot to order one with the kit, now I have to drill out the plate as well! So glad I got a drill press for Christmas. 

[Penguin]

Hmm, On the Dec axis, I drilled out the plate and the shaft was so snug I had to ease it in with a vice, so I've not bothered with any epoxy. We'll see how it goes.

I now have another issue on the RA axis: the sprocket is really loose one the motor shaft, like there is nearly a millimetre of play! I'll start another topic rather than hijacking this one and I've emailed Rother Valley Optics who supplied my the kit in case they can advise.