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N1LAF
08-14-2007, 04:41 PM
Couple years ago a friend gave me a tower with a CDR rotor, and a Mosley Classic CL-33 beam. Two weekends ago I poured the concrete for the base, and the antenna checks out fine. Last weekend I went after the rotor, rusty bolts and rusty plate expecting the worst. turns out that the bolts just broke free and didn't have any problems removing the rotor from the base. I figure I would get inside the rotor before i plug it in and give it a try. Good thing I did, this is what I am up against...

90 of the 98 bearings are rusted. The brake frozen locked. All the internal springs associated with the brake are broken. Looking at the Hy Gain rotor that is the closest to it, its $550 - $600 rotor. The electrical, no problem, and I have the can-do attitude, but I am not so strong on the proper mechanical handling. So I am going to rehabilitate this rotor, as long as it is not too expensive (ie, cheaper to buy new or second hand).

Should see the rotor control box, looks really old. Bet I could 'modernize' the insides.

This is what I have done so far:
1. Rotor is just about completely disassembled, all parts in one box
2. With help of penetrating oil, I have gotten the brake bar out of its slot (with the help of a screw driver and hammer).
3. Motor windings look great. This weekend I will give it the power on test to see if the motor works fine, and the brake coil activates.
4. I am loading up on the penetrating oil on the spring clips, if lucky, I will eventually be able to pull them out.

I think I can get replacement springs from True Value.

Here are my questions:
1. Where can I go to replace these round bearings?
2. What kind of lubricant will I need for the bearings when I put the rotor back together?
3. Best way to clean the junk off the rotor housing, and again with lubrication of moving parts?

Once I get the bearings and proper lubrication, no reason why i couldn't get this rotor back together. I'll take some pictures so you can see what I am up against.

N9FE
08-14-2007, 05:57 PM
most guys i know with rotators send them to the rotor man, 130bucks rebuilt, and he does a very good job, with a good gurantee to boot

N1LAF
08-14-2007, 07:00 PM
Pictures of rotor disassembled (http://paulfelgate.com/hamradio/cdr)

N1LAF
08-14-2007, 07:30 PM
I found this:

Norm's Rotor Service
448 Green Glade Rd
Birmingham, AL 35244

http://www.rotorservice.com/index.htm

This may be a better way to go.

N9FE
08-15-2007, 08:30 AM
I found this:

Norm's Rotor Service
448 Green Glade Rd
Birmingham, AL 35244

http://www.rotorservice.com/index.htm

This may be a better way to go. i'm pretty shure thats the guy

KF5ER
08-15-2007, 08:42 AM
C.A.T.S Online http://rotordoc.com/ did a very good job on my
old Ham IV and for a reasonable price.

Get the terminal board replaced with the plug in for the rotor cable and
get the heavy duty brake.

I installed the 5 second brake delay. Now the 15 year old rotor looks
and operates like a new one.

KB9ZGB
08-30-2008, 03:40 PM
bearing distributor international or motion industries for the bearings. give them the numbers off the bearing and race insist on timken or ntn or skf. a lot of cheepo bearings you will pay more for the quality. ohm the windings if more the .6 .8 take it to a motor shop and have the windings meged. if you have a lot of oil grease in the windings the deturgent proportys of the grease will toast the varnish on the winding wire. i.e. dead motor. if it megs ok a wash and bake of the winding may be needed. a good diaelectric grease will be needed in the bearings insist on c3 or motor grade. you dont want stray electical currant passing through the bearings to the mast to the ant to the coax to the radio. ect thought thats not apt to happen it should go to ground via the tower as far as the controller it will either work or it wont no need to moderize it not sure what else to tell you