AZ3 saddle and counterweight mod

[JamesF]

There are a couple of things about my AZ3 that I've never been happy with.  The first is that it has fittings for scope rings rather than a saddle for a dovetail which is a pain if you want to swap between scopes (or put an OTA on that is awkward to fit rings to).  The second is that the OTA doesn't tend to stay where it's put near the zenith.  I decided to fix both of these issues by fitting an aftermarket saddle and a counterweight bar.

The counterweight bar came from Astroboot though I was tempted to use some 22mm stainless bar and probably would have done so had the easy option not presented itself.  I bought a saddle from Sky's the Limit and realised there was going to be a small problem fitting it in that the grub screw tensioning the alt movement was going to foul the bottom of the saddle:

I undid the nut and threaded retainer for the worm, removed it and flipped the block the worm passes through over so the grub screw was underneath.  It's still reachable should I need to use it, but now out of the way of the saddle.

I then made up a piece of 5mm aluminium plate to fit down the centre of the top of the mount, drilled so it could be bolted on where the rings would normally go and for the saddle to be attached:

After I took this photo I actually put another hole in as it later allowed me to put one bolt through the saddle, retaining plate, mount and counterweight bracket all in one go.

The counterweight bracket itself was similarly cut and drilled, bent slightly to push the counterweight bar out at an angle.

That was pretty much it, really.  Then everything just needed bolting together:

The weight is a spare from my HEQ5.  I could really do with something smaller, but for the photos this one was handy.

And here's my ST120, riding at a rather jaunty angle...

James

[Alien 13]

Very nice mod.

Alan

[Peter Drew]

I have done a similar mod that carried a 80mm Ha telescope. I also used a number of smaller counterweights that screwed together offering different balance options for different altitude angles. Modified in these ways the AZ3 becomes a very useable mount. 

[Macavity]

Lovely job. I did eventually use tension springs. If you do try that,

be sure to fix them well. Or you could (sic) "have yer eye out"? 

Whatever, nice to make a genuinely useful mount of this thing...

[Merlin]

I counterweighted mine some time ago and it makes a big difference.My weight is much smaller ( 2kgs ), as I wouldn't burden the AZ3 with a 'scope bigger than my 102mm/f.5 refractor, and even this is a bit over the top.

[happy-kat]

So similar to what I have ready to rig up.

I have a 200mm threaded bar and 3x weights from astro boot that together total 1.3 kilo and two wing nuts either side on bar so can adjust position up/down. Your photo gives me confidence I will be able to balance my ST80 and 1100d now.

[Macavity]

Aside: Indicates a "gap in the market" maybe? Although I enjoyed my free-running "Giro"

mount, I eventually missed manual slow motions! A Vixen "Porta II" (A tad expensive?)

BUT you can add an Azimuth setting circle (+ Wixey) to an AZ-3 for "Push-To"...

[JamesF]

Aside: Indicates a "gap in the market" maybe? Although I enjoyed my free-running "Giro"

mount, I eventually missed manual slow motions! A Vixen "Porta II" (A tad expensive?)

BUT you can add an Azimuth setting circle (+ Wixey) to an AZ-3 for "Push-To"...

I've long thought that SW would be better off ditching the EQ1 and EQ2 and using the AZ3 instead, perhaps with a saddle and small counterweight.  The EQ1 isn't completely useless, but I think beginners buying at that end of the market would be better served by an alt-az mount than an EQ mount with no means of polar alignment that isn't really up to the job of carrying the OTA mounted on it in the first place.

James

[happy-kat]

I have a camera top mount plate on mine, good for my camera and good for my ST80 as mine has the drilled dove bar. My counter weight should allow me to use the camera and ST80 together.