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North Star Equatorial Platform


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North Star Equatorial Platform

I’ve never been much of an imager, as in lacking interest. As a kid, I was obsessed with clock drives simply because of the long focal length scopes of the time and narrow field eyepieces. It was probably more a technological interest than actually using one.

On the other hand, as I discovered the Dob, all thoughts of equatorial mounts went out the window. Now, even if I considered an SCT, it would be with a fork mount. No long exposures? Boo hoo.

A few years ago, on a hoot, I decided to get a cell phone adapter for my eyepieces. Given that my Dob is undriven, and after several awkward attempts, I got a few decent shots of the moon. However, the planets were another story, washed out, blurred, you name it. Then I got the idea for an equatorial platform. Guess I should’ve just left it at that, but when I saw an article on the North Star equatorial platform, the price was hard to resist. With their heavier model, it was more than enough to handle my 16-inch LightBridge. Uh, not exactly.

I ordered it last September and received the box, all excited for the new gear, a few weeks later. As soon as I opened the box, I discovered the base was broken. I mean, geez, I can’t even get it in the mail without something breaking?

Woohoo! It arrived!

Okay, so far. However, edge glued boards and not plywood? A bad sign.

Now we get to the base. Uh oh. Broken in shipping.

I contacted the maker and he said it would be better to ship it back Fed Ex rather than hassle with the original shipper (who I forgot). So, I boxed this part back up and sent it through Fed Ex.

They promptly delivered it to the wrong address.

After hassling with them for about a month, they finally admitted the mistake (multiple phone calls with a supervisor) and refunded the money.

I repaid for a replacement with the settlement and guess what? It arrived broken as well. Only this time, it was just a wooden foot, which I glued back on. No leveling yet.

Now, I have a complete platform but I noticed several things.

#1 The drive bolt isn’t machined. It was a regular threaded bolt with the threads ground off. It wasn’t even entirely round.

#2 The second thing was the wood drive surface on the top piece was only roughly cut, with lumps. This means, the thing would have a tendency to jerk now and then. I’d thought of doing the tweaks a few others have tried to resurface both things, but I just wanted to see what it did before I went any further.

The unit is supposed to handle up to 150 lbs and my scope is 130 total with everything. So, I set it up and noticed a few things.

#1 After going through a rigamarole to get the center bolt on the base of the Dob to fit in the hole (the base of the scope weighs about 50 lbs, I finally got the scope mounted

#2 When I tried moving the scope it bounced as if it were on a trampoline. Not good and I’m not exaggerating.

#3 It moved fine north or south, but if I tried moving it east or west, the scope had a tendency to tip off the platform.

#4 To reset it, there’s a small handle to pull the platform back in place after it reaches the limit stops. Okay, except you’re not supposed to drag it back while engaged with the drive bolt. That means having to lift up to pull it back, which could also miss the limiter screw, not to mention slightly lifting a 130 lb scope off the platform.

When I finally got it going, it seemed to work fine. It drove the scope, though not perfectly, but at least it slowed down the drift. With the scope sitting higher, I couldn’t reach my finder without getting on a ladder. That left it real awkward trying to get my Sky Commander alignment stars. I also had to reconfigure the Sky Commander a little bit for using an equatorial platform. It all boiled down to not being able to get a good alignment so this first time I set it up, I couldn’t find anything faint. I managed to get it on Jupiter by using my laser pointer (since the finder was still too awkward), and while there was drift, it was a lot better than no drive. However, I never could get the exact speed dialed in.

After getting up and running, I’d about had enough and packed it in. I left the scope as is and had a big surprise when I went out the next morning. The scope was canted over at a crazy angle because this happened.

The pesky edge-glued boards could not handle the weight.

Not only did it collapse, but it broke a couple of my cables which I had to replace.

It was already after the warranty expired, so I decided to take things into my own hands and I rebuilt the base. I decided to add a few improvements like double layered plywood, a larger compass, and a two axis bubble level. I also added adjustable feet.

Now, the tricky part was remounting the original hardware which was no mean feat as the top half is not exactly square, so the surfaces would not ride properly with the rollers on the base. Not only that but I had to resolder the switch wires which were just twisted together. All in all, it was a real headache to get the top to ride well on the base and it wasn’t all that good, but just cut it.

Because of weather and other circumstances, it was several months before I got to try it again, and while it worked better and subdued the bounce a little, I still couldn’t get it to track very well. Plus there was still the problem of being able to align the Sky Commander. That session ended with no results.

I got another chance to use it at a public event here at Red Rocks and when the platform slowed down the drift, it gave me a chance to show the moon to three people instead of two without a nudge.

The other night, October 7th, I set it up again and same issues, scope tilting, the finder too high, so on and so forth. I also noticed a few additional things that weren’t there before.

Here the scope is set up, ready to fall over as it’s aiming West.

But…

This is the top portion, the part that didn’t collapse. Notice anything? Those edge glued boards are not only cracking at the seams, but wherever they want.

The drive piece has a crack. Notice the rough cut along the drive surface after the stop.

A closeup of the other side, same thing.

I gave it a good try, but that night, I could not get it to track because guess what? The battery was almost dead after only using it maybe two hours total. I also could never get a good alignment with the Sky Commander so outside of looking at Saturn with it not really tracking (though I tried), it just wasn’t cutting it.

The next morning I removed the platform and set the scope back on the ground where it should be. To add insult to injury, when I set the platform against the side of the house, not only did the drive bolt fall off again (the set screw keeps working loose) but the bracket screws had come loose.

Needless to say, without the platform, I was able to align again, use my finder normally, and didn’t have to catch the scope from tilting over.

I had quite a productive night and once in a while I’d look over at the side of the house and see that disaster leaning up against the wall.

In summary, this is a half built, half tested unit and can’t even be shipped undamaged. It also cannot hold a 16-inch scope, no matter what the specs say.

I wasted $400 and came away with some unnecessarily damaged equipment because it collapsed on me.

If you’ve got a light scope and don’t mind the gross lack of precision, this might be the platform for you, but I wouldn’t use anything larger than a 12, and that’s pushing it, if you can even get it undamaged right out of the box. I’ve heard other stories of it working fine especially if tweaked, but in my experience it was an expensive failed lesson.


  • Tinker, Urban Observer, John O'Hara and 11 others like this


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