Welcome, Guest
Username: Password: Remember me

TOPIC: QUcik and nasty idea for an EQ mount

QUcik and nasty idea for an EQ mount 6 years 2 months ago #4489

  • CraziestOzzy
  • CraziestOzzy's Avatar
JUst a simple one, remember reading about it thrity odd years ago in an astro mag my parents used to get me. But plum forgot the details.
Is it possible to have an equatorial "mount" if I used a car axle and pointed the axle directly at the south celestial pole and drove the wheel hubs by a motor to keep track of the rotating star field?
Mounting the axle with a pair of "U" bolts onto something so that the lattitude is set and preserved, haven't gone there yet.
Just thinking big before going small-scale.

WIth the car axle being driven by a motor on the one end of the wheel hub, a camera fixed to the other end of the axle's wheel hub would allow complete sky coverage...BUT only if I used a ball head camera mount afixed to the wheel hub to hold the camera.

Just thinking out loud and if you have a name used in astro circles for this single axle drive would be great if you threw it my way so I can search a bit on duckduckgo.

EDIT: forgot to mention, I think single axis tracking systems are also typical for some solar panels that track the sun...albeit a bit crudely relative to the precision needed for tracking stars.
Last Edit: 6 years 2 months ago by CraziestOzzy.
The administrator has disabled public write access.

QUcik and nasty idea for an EQ mount 6 years 2 months ago #4490

  • Dave
  • Dave's Avatar
  • Offline
  • Administrator
  • Posts: 680
  • Thank you received: 28
  • Karma: 0
Yep - remembering that an EQ mount is exactly as you say aligned to the SCP and thus the only rotating element is RA. just have it moving at 15 deg / hr and you're on to it
Last Edit: 6 years 2 months ago by Dave.
The administrator has disabled public write access.

QUcik and nasty idea for an EQ mount 6 years 2 months ago #4491

  • CraziestOzzy
  • CraziestOzzy's Avatar
Yeah, thanks for that. As you know, been looking at the Double Barn Door drive.
davetrott.com/inventions/double-arm-barn-door-drive/
Despite the apparent simplicity of the design, there is not much room for error in various places during fabrication - which in contradiction, adds to the complexity if one wishes to have an error free tangent or expecially an easy means of aligning the hinge axis to the SCP. A type four Barn Door being a classic example of complexity and critical design/fabrication skills..
The basic Barn Door (type one) is a no brainer and easy to make in an hour, giving a good minute before any slew in tracking and appearance of star trails on anything over 50mm focal. The Type One drive shaft can even be turned by hand...one complete turn every minute if your thread count is 1mm.
But I am a lazy slob and also need my hands free during exposures.
So it got me thinking about using the concept of the Barn Door drive with respect to how it holds the camera and applying it to a typical German Equatorial type drive....but using only one rotating axis...throwing away the "junk" axis and keeping the all important one that lines up with the north and south celestial pole..
SUper simple and likely reinventing the wheel and my idea is far from unique.

So thanks again.
...and here is the idea I came across that got me thinking again about my car axle idea, it's the pic in the middle at the top of the page with a black scope.
astro.neutral.org/homemade-diy-gem-telescope-mount.shtml
DItch the entire Declination area and replace it with my camera and mount camera to the end of the RA shaft in similar fashion to the Barn Door method.
The only issues I need to contend with is aligning the main axle to the SCP.
I also think that having a long axis will make CP alignment a breeze in the park :silly:

So off now to the dump and car yards to find a lighter weight and smaller drive shaft than a car axle
Last Edit: 6 years 2 months ago by CraziestOzzy.
The administrator has disabled public write access.

QUcik and nasty idea for an EQ mount 6 years 2 months ago #4492

  • CraziestOzzy
  • CraziestOzzy's Avatar
Yup, similar has been done before, where a camera is attached to the end of the RA axis.
So this is basically what I am thinking of doing...
www.flickr.com/photos/edhiker/3132751114/sizes/o/in/photostream/

I think two collar bearings on the shaft will make this a solid idea and also light enough to fit in a backpack.
MUch like this guy here has done:
cdn.instructables.com/FAZ/YM78/GQX1NQMK/FAZYM78GQX1NQMK.LARGE.jpg

Also, those old Austar radar dish mounts with the adjustable threads (before they went to a roof top smaller version) have just what I need for getting the lattitude angle adjusted...
Last Edit: 6 years 2 months ago by CraziestOzzy.
The administrator has disabled public write access.

QUcik and nasty idea for an EQ mount 6 years 2 months ago #4493

  • CraziestOzzy
  • CraziestOzzy's Avatar


To make a long stroy short, three hours hard labour at the STuart dump...have my main RA shaft.
THose bolts/nuts were not easy to screw off :silly:
As this is a DIY project and I have just a few hand tools, have to be adaptable.
So, will have to see what I can get to turn this thing...pulley, gear or whatever I can scrounge and will fit without any machining or tech stuff.
I will be removing the pulley pictured, need something that requires less torque to turn.
THinking of a bike gear and chain, but will see what I can round up...a toothed pulley will be great, so liekly off to the wreckers as well as the Range dump tomorrow.

DIdn't find the bracket I wanted that holds those old Austar radar dishes, still looking.
Cheers
Last Edit: 6 years 2 months ago by CraziestOzzy.
The administrator has disabled public write access.

QUcik and nasty idea for an EQ mount 5 years 1 month ago #4617

  • Savarin
  • Savarin's Avatar
  • Offline
  • Administrator
  • Posts: 6
  • Karma: 0
dont go bicycle chain, too much backlash.
Toothed belt is better
The administrator has disabled public write access.
Time to create page: 0.349 seconds
Back to top