Low cost Odyssey Compact 10.1 modifications?
Posted 22 November 2013 - 04:34 AM
Posted 22 November 2013 - 06:37 AM
I've recently acquired a 10.1 Odyssey Compact. The former owner replaced the primary mirror with an Orion 10" f/4.5 and added a University Optics right angle finder, so it seems like it will be a fine scope as is, but are there any modifications I can make that will improve usability without breaking the bank?
A few thoughts:
- How's the focuser? A better focuser can make a real difference and the Coulter focusers were pretty basic/crude.
- Primary mirror cell: Does it all proper ventilation of the mirror and accurate collimation? Is it pinching the mirror?
- Secondary spider.
- How is the action, is it smooth? Improving the bearings can make a big difference.
Posted 22 November 2013 - 05:40 PM
Posted 22 November 2013 - 06:36 PM
Posted 23 November 2013 - 05:49 AM
Thanks for the suggestions Jon. I think the bearings will be a good place to start.
Like they say, we want:
We want photos...
Posted 23 November 2013 - 10:21 PM
Posted 02 December 2013 - 01:50 AM
Telrad & telrad riser - I'm lost without one. I added a mirror fan. 2" SkyWatcher dual-speed Crayford + weights to balance. DIY digital setting circles - hardware software, I did this: https://github.com/mdw123/arduino-dsc. Mounting the encoders to the Odyssey wasn't hard. I can post pics, if you want a hint.
Posted 07 December 2013 - 12:35 PM
Here's how I mounted my encoders:
For elevation, I used t-nuts and these handles along with a piece of 1/8th inch plywood and plastic bushings to help keep the plywood from rubbing on the moving parts and to properly engage the encoder. I epoxied the plastic mounting shell of the encoder to the plywood over a hole that the encoder shaft protrudes through. I then could snap the encoder into the plywood mounting arm.
The encoder shaft was a wood screw to 1/4" thread piece of threaded rod. I used the same circle-of-paper trick to mark the center of the round disc that you would to mark the center of a mirror. The Odyssey has a metal disc on that I needed to drill through, so don't expect you're mounting this on wood as I did. It worked out well anyway.
The AMT-102 capacitive encoders I used have a flaw in that the shaft adapters (at least mine) tended to slip and come off. I lost one at a star party, and you can imagine how difficult it was to find that little piece of plastic. I permanently mounted them with t-nuts.
The axis bolt was much easier. I basically copied what someone else did, but had to refurbish my axis bolt first.
I replaced the 1/2" bolt on my Odyssey with a 1/4" bolt. The wood had worn significantly. so I drilled and plugged the hole with a dowel then re-drilled it.
I use a t-nut with a threaded screw through the bottom of the base board, to avoid slip I applied loc-tite to every thread where I didn't have a nylon lock nut, including the interface between the screw and the t-nut. On top of the base board I countersunk the hole with a 3/4" paddle bit and used a washer and a thin nut with loc-tite to ensure that the shaft was completely solid on the base board.
I drilled the base to 1/2" and inserted and shimmed a plastic bushing cut to the thickness of the base. This should avoid the wear issues from before as the particleboard does not do well with the rubbing of the bolt threads. Maybe the plastic will have the same issue, but theoretically I can replace that. I'm looking to do that job in 2025, considering the original life of the shaft.
Using a couple of smaller plastic bushings to create stand-offs, I used a couple of small wood screws to mount the encoder to the base. The base turns around the shaft.
Slip is your enemy. I used loctite on every bolt/nut connection and ultimately needed to epoxy the shaft adapters to the bolt, which means I'll have a hard part taking the shaft off of the base board unless I cut it with a hacksaw. I don't expect to need to do that. If I do, AMT customer service has been good about helping replace the little bits that have been lost or broken on their encoders.
There's only one thing I would change that I can think of now. I don't like the bolt sticking out of the elevation pivot all the time. I might try to create a t-adapter for the elevation axis with another T-nut and use industrial strength velcro to mount the elevation shaft so that I can remove it for transportation.