How to covert a polar mounted c dish to a stationary dish (without actuator)?

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skipticum

SatelliteGuys Family
Original poster
Dec 14, 2009
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ottawa
I have two 7.6' unimesh dishes (donated to me) each with an old rusty actuator. Since I'm only interested in two sats (one dish for each sat), and I doubt if the actuators are still working, I'd like to setup the dishes as stationary dishes. I'd like to either remove the actuators and find an alternative way to prevent the dish from moving freely sideways Or be able to set up the dish(es) as stationary with the actuators attached to keep the dish from moving to the sides. My question is which way is better? And do I have to still account for declination offset for staionary setup with a polar mount designed dish (or ring)? Thanks.
 
I'd align the polar mount to track the arc. Then it's quick and easy to change the satellite it's fixed on. This way the skew is self adjusting. Shouldn't be too tough to just push the actuator in/out to change sat. Or fashion up a rod to take its place, thru a block with a bolt to lock it in place. Check the actuators with a 12v battery, I've seen some pretty rusty ones still working.
 
Thanks Fat Air for the reply.

The problem I have with the actuators is that they're frozen/stack because of rust, and I cannot move the rod in and out of the tube. I do have a 12 v battery, but I have to check if the actuators take 12 or 24 volt. For now, I like the idea of replacing the actuators with a rod (I still have to figure out a way of locking it in). The actuators motors may be still ok, it just the push rods are rusted. One day I'll try to take one of the actuators apart and attempt to refirbush it.
 
You won't hurt the motors with 36 volts (for short bursts).
They're either designed for 36 or for 24 volt operation.
So, 12 volts will just move 'em slowly, if at all.

I'd take one off and gently disassemble it (take pictures so you know how to put it back together).
There's a very good chance you can free it up, and get it working again.

However, the hardware stores have large diameter threaded rod stock in two or three (?) foot lengths.
You could get a piece of that, some nuts and washers, and probably fabricate something to hold your dish in place.

I still vote for working on the motor, though.
In a previous thread, Pendragon described restoring a rusted-up H-H mount that was well beyond its freshness date!
I think an oil-soak was largely responsible for that success. ;)

edit:
Okay, one last thought...
Hardware stores will have aluminum or steel L-bracket material, either drilled or not.
It's one inch by one inch and multiple feet long.
Cheap, easy to work with, etc. Be creative. :)
 
I've also heard of somebody that used two turnbuckles to position a dish without a motor, with one on each side of the dish. They're not terribly expensive.

I'd also make the attempt to get the motor going again as well. Even if the threaded rod is all rusted up, a wire brush on a drill, penetrating oil, and possibly a torch will fix that right up. I could barely make out the threads on the first motor I'd gotten with a BUD. 45 minutes later it was moving. I'd used the wire brush to clean off the threads. Around the acme bolt I used the penetrating oil and the torch (to break the rust away with the heat) and got it to move back over the threads I'd already cleaned. Then I did the other end of the threaded rod with the brush as well.

The acutator I'm using now had the permenant magnets break off the motor housing and would stick to the rotor, causing the motor to jamb. I used super glue to glue them back to the motor housing in their original positions. I could see the outline of where they were originally and put them back in the same places.
 
Well, I removed the cover of one actuator to expose the electronics and the gear box. I was surprised to see that all look in mint condition (I didn't realize that all gears are plastic). One problem though, it appears that the lubicant has dried solid and is acting as glue holding the gears stuck together: is there a recommended product that I can use to loosen up the dried lubricant without damaging the plastic gears or anything else?

It seems that if I can get the gears loose, I may be able to make the actuator work again after removing the rust and add some lubricant.
 
To clean it up - I'd disassemble taking pics, marking parts, writing notes, whatever, to reassemble it correctly. I'd use hot soapy water and an old tooth brush. I like to use DAWN. it cuts grease well. For a new lubricant, I've always used an aerosol lithium grease. I use a General Motors product that's safe for use on plastic. It also doesn't get hard in the cold.
 
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