How to Equatorialize a dobsonian

[EA2007]

Pretty simple 'acey', just point it north!

I don't think at this stage it needs a perfect alignment, I aren't doing any photography, so a rough polar alignment is all I require.

All that is needed is to locate Polaris, aim the fork arms towards that location and then set the scope up so that it is tilted at the same 34 degrees as the arms, look through the eyepiece for Polaris and align from there. Good idea to use a laser pointer for this, saves getting into stupid positions and getting the wrong star.

Hope this helps.

[acey]

You mean you point the dob straight "up" to aim it at Polaris? (ie at 90 degrees to the wedge-top and dob base). Your pic of the scope aiming "north" shows it at an angle, which kinda threw me - but I suppose your daytime/indoor view of Polaris wasn't perfect.

Andrew

[EA2007]

You position the black wooden base (mount) in such a way that the fork arms are pointing due north.

From this you then insert the OTA, because the wedge is at 36 degees, a tilt of the OTA on a 90 degree right angle will have it aimed at Polaris, I shall draw an image for you to clarify:

[acey]

All is clear - many thanks!

[Doc]

http://www.roundtableplatforms.com/

I use one of these on my 14" Dob, it works a treat.

Gaz can you tell me if they ship this to the uk.

Btw EA you have done yourself proud, looks really good.

[EA2007]

Cheers Doc, I have to award the effort to my dad though, he got the wood and stuff for it.

Just after a motor for it, but its not deperate for the moment

[ngc2403]

that look great,

really nice job mate

[Chris Stacey]

Cheers Doc, I have to award the effort to my dad though, he got the wood and stuff for it.

Just after a motor for it, but its not deperate for the moment

I liked your design so much I decided to try it myself.

Have you had any joy with the motor yet?

[Lux1]

Reviving an old thread here, - has anyone managed to motorise this type of mount and if so how did you do it? I knocked a similar mount up today for my skywatcher 130 dob. In theory it will work, seems stable, eyepiece is always easy to get to, however I think due to more sideways stress than the poncet mount a motor with a stronger torque may be required. Any ideas for a possible motor, - I dread to think about stepper motors, I was moreso thinking about a cordless screwdriver with adjustable speed and reverse? I will try to post my photos over the next day or two.

[pixelsaurus]

Any more updates on this? Having bought a dob last year, I'm intrigued by this possibilities of this. Somewhere between a fork and a horseshoe mount. Perhaps the central pivot pin should be replaced by something like a stub axle. Use skateboard wheels to help support the outer rim (a la horseshoe) and then drive the system as normal.