Hello!
First, a thanks to K5LAD for publishing his illustrated Tailtwister repair page
http://www.hayseed.net/~jpk5lad/Rotors/Tail-Twister.htm
I'd never tried servicing a rotator before and this weekend was my first try.
I was able to get the whole thing apart, replace all the races and bearings and
the direction pot, grease it up and put it all back together without much
trouble.
I sat on the back porch with the rotor, tools and a laptop open to the K5LAD
page to accomplish it. Took about 4 hours total including pulling off the old
terminal strip and replacing it plus adding a trailer hitch disconnect.
I had some notes to add if anyone else is of a mind to try this in the future.
1) If you don't have a pole mount like K5LAD, I used a cinder block with a
cardboard shim. Put the rotator in one of the holes of the block upside down.
By happy accident, the other hole was a convenient place to stick the other
half of the rotator once I'd taken it apart.
2) A notation is made about using a container with sides under the rotator to
catch the bearings WHEN they fall not IF. I put the cinder block inside a
cardboard box. You will be chasing ball bearings. They pop out of the races
easily. Don't skip this.
2) The replacement of the indicator pot was easy. Pull off two sets of screws
and washers, unsolder two wires, solder wires on new pot, reinstall hardware.
3) K5LAD mentions you'll need two packs of MFJ replacement bearings to redo all
of them. Uhm, yeah! I had one pack. I was short a whole bunch of bearings.
This was easy to remedy -- the bearings inside the top most race still looked
new and shiny. I just cleaned off old grease, washed them up, and re-used
them. New bearings inside the other races.
4) I used white lithium grease to re-do all the bearings.
5) All the talk about making sure the W shaped part of the pot is inside the
top slot and making sure the rotor control box indicated 360 degrees of
rotation -- I did this. It worked great. Except, when I turned the rotator
over it slipped JUST A LITTLE and I popped it back into place. This was a
mistake. Because I put it all back together and guess what? It had popped off
enough to get the little W out of place and I had to take the whole thing apart
again to reseat the pot in the right place. If the rotor slips, start again,
rotate it again, make sure it still works before putting the other races on and
the half with the brake engaging grooves.
6) The new races are a little unwieldly, especially because you have to chop
the bottom most race from 49 to 40 slots with a cutter. It was not easy to
slip the bottom half of the rotor back on because the race wasn't just exactly
circular around the bottom -- it stuck off a little. I used a drop of
superglue to glue one end of the race to the other and then the rotor went back
together easily. The race and/or bearings popped off several frustrating times
before I did this.
7) I pulled off the old rusted terminal strip and replaced it with a new
HyGain/MFJ part and was dismayed to find the two screws that hold the sides of
the terminal strip on are not included! If the strip is rusted enough to
warrant replacement, those screws are going to need it also. I still have to
get these at a hardware store or something.
8) Pulled all the screws out of the terminal strip and ran wires for a female 8
pin trailer hitch disconnect through the holes to the internal wiring of the
rotator, sealed holes with RTV. Now if one of my other HyGain's is wired with
a hitch DC the same way, it will make swapping out a rotator that much easier.
This project I would rate as tedious, time-consuming, yet easy. I'll be that
much more prepared to do it the next time.
Scott W4PA
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