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[magic612]

I bought a 5" f/9 achromatic refractor about - hmmm... 3 year ago or so (?). Nice scope, though the focuser was a bit iffy. Anyway, at the time, I didn't have a suitable mount for it. And since I couldn't afford to buy a suitable mount at the time, I did what I usually do in those situations: I made one!

Started out as an alt-az with a BIG tall tripod with a lot of "swing" over the top. Not only was this too tall, it was too heavy and awkward (note 25 lb counterweight on opposite side of the azimuth section):



So I did what I usually do in those situations - I REbuilt it!



Ahh... yes, MUCH better. Not as awkward, lighter, and easier to transport. But still not "good enough" for tracking at higher power. When I finally was able to afford a decent EQ mount (an Orion SkyView Pro), I knew I had the right head. Problem was... the pier was too short.

So over the last two weeks or so, I purchased the right aluminum tubing and other hardware to make it work.

(Details and more pictures coming soon!)

[magic612]

And... here it is!



One more shot:



This wasn't all that difficult, really. I cut the 60" tube to 52" length. Then I drilled the three holes for the legs, three more 5/16" holes for the tension rods about 40" up (or so), and finally the holes for the eq head to mount to the top. I used a 1/4" die to thread the 1/4" diameter aluminum tensioning rods, removing one of the original turnbuckle eyebolts and placing the threaded rod in the turnbuckle instead. I'm not 100% certain like the "bent hook" option where the rods insert into the pier - I may add eyehooks and turnbuckles up there too. And lastly, I drilled holes into the legs to insert some U-bolts so the turnbuckles can hook in there, squeezing the U-bolts in a vise to ensure that my 10 lb weights can fit over them. That way I have more mass at the bottom of the legs/pier rather than having 95% of the mass 5 feet up. No "tippy" scopes, please.

Voila! A new pier, and one I am excited to use for the next time I am at a Chicago Astronomer event!

[erikruud]

Nice!

Now add some brass and copper accents and you can say it's "Steampunk".

[magic612]

Hehe - thanks Erik. Now if I could actually AFFORD the brass and copper accents, I might do that! I went with the aluminum mostly because 1) it was the cheapest material I could get that didn't require a lathe to change the internal diameter for the EQ head and 2) it was lightweight. Oh, did I mention it cost about 30% of what the same thing would have cost in steel?

[Chicago Astronomer - Astro Joe]

Dave,

Your are too cool man.

I dig it all, even the first prototype of the mount for the refractor.

But, please to explain the need for the tension rods. Since they are not secured to the ground, my feeble brain isn't registering. Does it minimize plumb movement even if it's self contained? What about uneven surfaces, how does it handle that? And finally, is it top heavy?

I'm with Erik...go for the steampunk look!.... ;D

[magic612]

Hey thanks Joe!

They don't need to be secured to the ground; what they are doing is what you suggest: Maintaining plumb. Because the legs are only attached with one screw each, and aluminum has a tendency to flex somewhat, the tension rods keep each leg "taut" in place, by pulling on the screw holding it in the aluminum. Without the rods, the pier will sway rather substantially (literally, a couple degrees without too much effort). With them, it barely moves, and strengthens is with minimal weight or fuss.

For uneven surfaces, it needs some wood blocks to level it, but I have plenty of those laying around my garage, and will bring plenty of thicknesses with me to ensure level/plumb when setting up.

[erikruud]

Use large vertical bolts and the end of each leg for leveling.

[Chicago Astronomer - Astro Joe]

I hope to catch your mount sometime before the cold weather sits in.

I'm thinking about a session Sunday or Monday...depending on conditions.

[patrickm]

Woah! SA--LUTE!

Attachments:

[erikruud]

You could chuck a wire brush in your drill and give that big aluminum tube one of those swirly brushed finishes to dress it up.

[magic612]

Oct 27, 2011 17:58:33 GMT -6 erikruud said:

Use large vertical bolts and the end of each leg for leveling.

Erik, I did consider that. Problem is, I couldn't figure out a good way to do that and still use the tension rods, especially with the weights. Additionally, the bolts would work fine for hard surfaces, but would still require wood "feet" on grass and other soft surfaces. So ultimately I decided the KISS principle (Keep It Simple, Stupid!) was the best option for that.

[magic612]

Oct 27, 2011 19:38:24 GMT -6 Chicago Astronomer - Astro Joe said:

I hope to catch your mount sometime before the cold weather sits in.

I'm thinking about a session Sunday or Monday...depending on conditions.

Hopefully Sunday - Mondays are more challenging for me since I have work the next day and it's a haul back home from Adler.

[magic612]

Oct 27, 2011 21:09:50 GMT -6 patrickm said:

Woah! SA--LUTE!

Thanks Patrick! ;D

[magic612]

Oct 28, 2011 6:19:04 GMT -6 erikruud said:

You could chuck a wire brush in your drill and give that big aluminum tube one of those swirly brushed finishes to dress it up.

Haha, good idea Erik. Actually, that's why I've got the "almost" in the title of this thread. The pier isn't "finished" yet. I was thinking about getting it powder coated, because that's some seriously tough stuff, and there are some really cool colors out there. The other thing I considered was having it polished and then clear-coated; I know a guy up in Carol Stream who can make polished aluminum look like chrome, and powder coat that clear or with a transparent candy-color, and WOW! Look out - the visual on them is amazing. But that's also likely a $150 or $200 proposition, so I need to make a bit of extra spending money before that happens.

The important thing at the moment though is that it's FUNCTIONAL!

[Chicago Astronomer - Astro Joe]

I like the Rustoleum "Hammered Metal" paint.

Tough and looks good.

I used it on my tripod and C11 mirror cell housing.

But...I think you should etch screaming skulls on it....or Hello Kitty.

[erikruud]

Oct 28, 2011 8:02:36 GMT -6 magic612 said:

The other thing I considered was having it polished and then clear-coated; I know a guy up in Carol Stream who can make polished aluminum look like chrome, and powder coat that clear or with a transparent candy-color, and WOW!

Functional is always good, but now I have to wonder if you are spying on me. I have been considering a candy finish for my PVC/Binoc finder scope.

[magic612]

Oct 28, 2011 8:54:56 GMT -6 Chicago Astronomer - Astro Joe said:

I like the Rustoleum "Hammered Metal" paint.

Tough and looks good.

I used it on my tripod and C11 mirror cell housing.

But...I think you should etch screaming skulls on it....or Hello Kitty.

Rustoleum works great on steel. Aluminum usually requires anodizing or chromate conversion to achieve best adhesion for regular paint. I figure by the time I get that done, I might as well just get it powder coated, and that's super tough anyway.

Hello Kitty... hmmm - there's an idea.

[magic612]

Oct 28, 2011 9:04:36 GMT -6 erikruud said:

Oct 28, 2011 8:02:36 GMT -6 magic612 said:

The other thing I considered was having it polished and then clear-coated; I know a guy up in Carol Stream who can make polished aluminum look like chrome, and powder coat that clear or with a transparent candy-color, and WOW!

Functional is always good, but now I have to wonder if you are spying on me. I have been considering a candy finish for my PVC/Binoc finder scope.

Of course I'm spying! Isn't that what we all do with our telescopes?

[Paulie pchris00]

Nice job.

I liked the 2nd version of the original mount, too.

Was the barbell secured at all on the original mount, or was it just hanging there???

[magic612]

Paulie, thank you. The second version did work very well - it was just hard to keep planets centered when doing outreach with the magnification at 150x. On the first mount, the barbell did have a small latch that kept it in place so it wouldn't accidentally fall.

[magic612]

And here's what I did with the "leftover" piece of aluminum tubing. I bolted a couple of short, pressure-treated 2x2's to it, drilled holes in them, and attached my previously-made adjustable wood tripod to it. Those fender washers you see are the "south" side of the mount (the other sides are regular washers), so the head can be mounted more quickly, as I know where that part of the mount should be on the tube:



Unfortunately, the center support braces for the tripod were made for a slightly smaller diameter eq-head/mount, so the angle to the ground makes the tripod a little more "tippy" and not as stable as I'd like. So I will probably re-drill the holes for where that mounts to the legs themselves (placing it higher up), which will increase the stability.



It doesn't work quite as well for the 5" scope, but that's okay - I now have a very stable and easily adjustable "grab n go" set up for my 90mm refractor. I can pick the whole thing up with two hands and walk out the door.

[Paulie pchris00]

Very nice!

I can see why you'd need to drill new holes for the tripod, though.