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Three Simple iOptron Improvements
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Three Simple iOptron Improvements
Michael A. Covington
Michael Covington is the author of Digital SLR Astrophotography and observes clouds, and sometimes celestial objects, from Athens, Georgia.
In what follows I want to tell you about three things I've done to improve my early-model iOptron GEM45 mount. With a bit of adapting, you can apply the same ideas to many other mounts, both iOptron and other brands.
1. Better saddle knobs
Fig. 1: Saddle knobs made from bolts and wing nuts. Note also added declination index mark.
After finding the original iOptron saddle knobs hard to turn, and even experimenting with larger knobs from an industrial supplier, I figured out what I actually needed to do: make my own out of bolts, wing nuts, and ordinary nuts. Because the GEM45 saddle has been through several engineering changes, I'm not going to give exact specifications; instead, remove one of your existing knobs, go to a hardware store, and see what you can put together to substitute for it.
Fig. 2: A hex-socket-head bolt, a wing nut, and two ordinary nuts make a good saddle knob.
Mine had M4 metric threads, and I was able to build the new knobs around hex-socket-head bolts that take the same hex wrench as the mount uses for polar axis adjustment. Now I can tighten and loosen them by hand and also use the wrench if they get stuck. After confirming sizes, I put a dab of epoxy on the threads to hold the nuts onto the bolt.
2. Index marks
Unlike Celestron mounts, iOptron mounts don't have index marks to show zero position. That leads us to do various tricks with bubble levels and the "Search Zero Position" electronic function on mounts that have it.
But index marks are easy to make. I used white-on-black tape from a Brother labelmaker with just the letter I printed in the middle of each piece. You can see the added declination marks in Fig. 1 above, and the R.A. marks in Fig. 3 below. They aren't perfect, but neither are the index marks on any other mount; they certainly make it easy to get close to zero position quickly, and to confirm that you've returned to it at the end of a session.
Fig. 3: Added index marks for right ascension. (For dec. index marks, see Fig. 1.)
3. User-friendly labeling
Good labels on scientific equipment make it easier to use and prevent mistakes. And if they make it looks a bit less elegant, a bit less like fine furniture and more like a piece of laboratory equipment — well, that's what it is!
Fig. 4: Added labels prevent mistakes and make equipment easier to use.
With that in mind, I've added several labels to my GEM45 to indicate what I normally plug into each socket. Besides what you see in the picture, I added, elsewhere, a label with my name, cell phone number, and e-mail address, and another saying "Delicate equipment — iOptron GEM45 mount — read instructions before moving or handling," just in case someone else, perhaps a non-astronomer, has to handle my mount in an emergency. These were made with a Brother labelmaker that was connected to a PC and equipped to make larger labels.
- eros312, darkstar3d, rekokich and 17 others like this
Love the DIY saddle bolts. The star knobs on my ZEQ25 are plastic and smooth; possibly the worst in the hobby.
I was going for that true ‘lab look’ and went with blue painters tape and a Sharpie…
White artist's tape (removable, opaque) and a black fine-point Sharpie are one of my standard labeling methods. Very easy to read by dim flashlight. The tape can be cut to any size... the Sharpie has no problem with schematic symbols or Greek letters...
Your index marks look more professional than the pencil on masking tape marks I currently use on my ieq45.
Here’s one: I replaced the metal washers on the bolts that hold the mount to the tripod with nylon washers, after someone’s suggestion here. I can tighten down the mount and still make azimuth adjustments.
I have a GEM45 that's 'bone stock', if you will. I agree the saddle knobs aren't my favorite and now I use a big hex key 100% of the time I put equipment on the rig. I've actually had it cost me about $500 already in damaged gear that fell.
In the end it's really picky about how it's handled - and then really hard to handle when doing so correctly....
Thanks for the great tips, though!
I actually put a label on the front of mine that says:
iOptron GEM45 equatorial mount
PLEASE DO NOT HANDLE OR MOVE
WITHOUT KNOWLEDGEABLE ASSISTANCE
This is in case I have to leave it set up while attending to an emergency, or am sick or injured while observing, or someone comes upon it while I'm away from it. My family has been instructed that if for any reason I am not able to take it down myself, they should disconnect all sources of electricity, throw a waterproof cover over it, and get a knowledgeable person to come help.
Get a BROTHER P-Touch label printer.
If you like organization in your life, then this is the tool.
mine is an older H-100. Just amazing.
I have a small fleet of them (I think 4 total), one of which connects to my PC and can print any typeface, even graphics, on tape up to an inch wide.
In my earlier career I ran the artificial intelligence laboratory of the University of Georgia. Lots of computers, some of them specialized, and also rather rapid turnover of the students working there, because most were in a 2-year master's degree program. As you might imagine, we used LOTS of labeling. (IP addresses on printers, basic operating instructions on lots of things...) One fellow complained, "This doesn't look corporate -- it looks like a laboratory." To which I replied, "That's what it is!"
I label astronomy equipment copiously, too.
Are the original knobs that bad? On my CEM40, they are fine.
I also have a CEM40 and found the knobs a little "finicky" - they would seem tight, but be just loose enough for my scope to slip. I got 2 Eklind ball-head hex screwdrivers from Amazon [https://www.amazon.c...e?ie=UTF8&psc=1] , fantastic solution. Very easy to tighten the 6MM hex bolt for the knobs now and the 4MM make it SO easy to assemble the head to the tripod:
Good, simple fixes for nagging issues.
Problem with a lot of mid-line equipment are poor tolerances, right down to the tapped holes in things (I've seen bolts rock side to side owing to this) and cheap, course anodizing which inexplicably, they sometimes put on the threads of a tapped hole. Be much better if they'd just leave it as raw aluminum but cut it right in the first place. That pretty much goes for all thread cutting from China, not just bolt holes.
Index marks are a necessary addition to these mounts. Right now I just use a Sakura silver-colored Pentouch to place marks. The ink is permanent but my mount (CEM25P) has a off-white paint scheme so I first made a black background with a sharpie. I like your label maker idea, much cleaner way of doing this!
Great Idea, even if I do not own one of these mounts. Nate Goodman (Nato). Salt lake, Utah.
To me, the worst part of the mount is dealing with the two bolts that connect the mount to the tripod. The hex wrench takes forever, and the vertical clearances are so narrow, so I used this: https://www.amazon.c...0?ie=UTF8&psc=1
It still doesn't quite fit in there, the wider bit holder presents a bit of a challenge, but you can get enough of the bit in there to screw in/out most of the bolt, and finish off with the hex wrench.
Yes, I use a ball end hex screwdriver for the same purpose.
I don't beleive they are for my version of the GEM45.
I'm assuming there was 2 different variations of saddles.
Also 2 different versions of mounts with electronic ports in different positions.
At least 2 versions of each of the things you mention.
I did the markings on ra and dec on my ieq45pro many years ago and it works great for referencing home position.
Great article Michael! I've got a T-wrench for my GEM45 saddle knobs but may look the type of knobs you've made.
I really like my CEM40 except for the saddle knobs that are hard to tighten, and the fact that the saddle has to be modified to switch from Vixen to Losmandy plates. I contacted Anthony at ADM and he has just released a saddle for the GEM45 that also works for the CEM40. It actually uses an adapter plate to mount one of his saddles onto the CEM40. I am the second customer and it works well. Now I can switch scopes without having to modify the saddle and the saddle knobs are much easier to use and the saddle is smooth and secure. Here is a link to the product. Needless to say this is a much more expensive solution.
Already had 2 out of 3, Index marks are next. Nice article.
Threads in aluminum usually suck, especially if the piece is only a couple or three threads deep. And they're even worse if done sloppily loose or overtight because a worn tap was used. The best cure (if it can be done on a given piece) is to drill the holes bigger and tap them to accept helicoils.