I just installed my third HAMIV rotor; I got about 4 years each from
the previous two. The most recent failure was the pot, with 5-6 turns
worn through at the spot I usually leave the rotor. Makes me think
the brake wasn't working very well. The previous unit was freewheeling;
I don't remember exactly what was wrong. The screws holding the case
together are always corroded in place so any repair becomes less trivial
as they break off. And anyway the inside usually looks bad enough (with
lots of rusted ball bearings) that repair is unappealing.

On the current (new) unit I noticed that one screw hole for the control cable
cover plate was stripped (and they should have noticed too since the screw
was hanging out) and one mounting screw hole was not tapped to full depth
(I had to get a shorter bolt).

I bought the first HAMIV about 8 years ago to replace a HAMM from the
60's (IIRC). They say the HAMIV is an improvement but it certainly
doesn't seem to last as long. Is there another rotor with the same
mounting pattern that might be better? It's an inside-tower mount
so I'm kind of constrained. Maybe I should look at rebuilding the HAMM?
It was seized but I still have it.

If anyone wants the two failed HAMIV rotors for parts let me know or
I will probably toss them soon...

Dan Lanciani
ddl@danlan.*com

"Dan Lanciani" ddl@danlan.*com wrote in message
...
I just installed my third HAMIV rotor; I got about 4 years each from
the previous two. The most recent failure was the pot, with 5-6 turns
worn through at the spot I usually leave the rotor.

That sure sounds like a short life for a rotator. As you have it inside the
tower (?) I guess that you have a thrust bearing at the top of the tower.
Are you near the salt water or in a very windy place ? Do you contes with
it and turn it a lot ?

I put one up about a year ago that was used,but rebuilt. I am not in an
area that is very hard on the rotators. I hope it will last longer than 4
years. It is in the tower about 5 feet down and I have a thrust bearing at
the top. Just truning a 3 element tribander and beams for 6,2, and 432 on
15 foot booms.

In article , (Ralph Mowery) writes:
|
| "Dan Lanciani" ddl@danlan.*com wrote in message
| ...
| I just installed my third HAMIV rotor; I got about 4 years each from
| the previous two. The most recent failure was the pot, with 5-6 turns
| worn through at the spot I usually leave the rotor.
|
| That sure sounds like a short life for a rotator. As you have it inside the
| tower (?) I guess that you have a thrust bearing at the top of the tower.

There is a collar; I'm reluctant to elevate it by calling it a bearing but
it does prevent any significant mast bending moment from reaching the rotor.

| Are you near the salt water or in a very windy place ?

Yes, about a block from the ocean.

| Do you contes with
| it and turn it a lot ?

I don't turn it a lot and I always leave it in the same position since
that is the position that allows me to lower the tower and I wouldn't
want it stuck in some other position. Obviously this isn't great for
the pot if the brake isn't working well.

But none of this explains the reduction in life compared to the old HAMM
(I think we are talking nearly an order of magnitude) or the screw hole
tapping problems with the latest unit. Was there a stainless bearing
option (perhaps third-party) for the HAMM? That might have had something
to do with it. Other than the bearings (and of course the pot) the latest
failure doesn't look *too* bad inside.

Dan Lanciani
ddl@danlan.*com

Dan,
I think you may have answered one or two of your complaints. I
also think you have had a couple of 'manufacturing defects' that the
company really ought to fix.
Because of where you live, you are going to have corrosion problems
no matter who makes your rotor. About the only simple means of
reducing that corrosion problem is regular maintenance, more regular
than 'normal'?
Two 'duds' in a row is sort of unusual. That tends to tell me that
quality control may not be the 'best' in the woprld, or at least could
be a little better. I'm sure they won't jump for joy with another
complaint, but I certainly think I would complain if it were my rotor!
Good luck.
- 'Doc

wrote in message
...
Dan,
I think you may have answered one or two of your complaints. I
also think you have had a couple of 'manufacturing defects' that the
company really ought to fix.
Because of where you live, you are going to have corrosion problems
no matter who makes your rotor. About the only simple means of
reducing that corrosion problem is regular maintenance, more regular
than 'normal'?
Two 'duds' in a row is sort of unusual. That tends to tell me that
quality control may not be the 'best' in the woprld, or at least could
be a little better. I'm sure they won't jump for joy with another
complaint, but I certainly think I would complain if it were my rotor!
Good luck.
- 'Doc


Dan,

Since you live so close to the ocean, you might want to try and coat (spray
paint) the rotator assy with NEOPRENE PAINT. (This paint is waterproof &
impervious to salt water & diesel fuel and you should be able to find it in
either a well stocked hardware store or paint supply store).

You also might want to coat any open antenna connectors as well as any
coaxial connectors.

Your other option would be to coat your rotator with a 2-part epoxy based
paint, although this is rather expensive, and if you had to take the rotator
apart it would be a BEAR OF A JOB! Personally, I would stay with the
NEOPRENE!

my $0.02
73's de Howard W3CQH

In article , (W3CQH) writes:
|
| wrote in message
| ...
| Dan,
| I think you may have answered one or two of your complaints. I
| also think you have had a couple of 'manufacturing defects' that the
| company really ought to fix.

Yeah, but somehow it didn't seem worth the bother. I was up on the tower
when I discovered the short-tapped mounting hole and of course at that
point it was easier to get a shorter bolt.

| Because of where you live, you are going to have corrosion problems
| no matter who makes your rotor.

Although the corrosion makes the rotors unappealing to work on I don't
think it was the cause of the failures.

| About the only simple means of
| reducing that corrosion problem is regular maintenance, more regular
| than 'normal'?

Perhaps, though I still wonder why the HAMM faired so much better. In
order to do any kind of regular maintenance I think I'd have to replace
the bolts that hold the case together with stainless in advance since
they rust in place very quickly.

| Two 'duds' in a row is sort of unusual.

Three duds...

| That tends to tell me that
| quality control may not be the 'best' in the woprld, or at least could
| be a little better. I'm sure they won't jump for joy with another
| complaint, but I certainly think I would complain if it were my rotor!

Yeah, again it just doesn't seem too productive. I'm sure they would
be happy to have me ship back the latest one and I could wait around for
a replacement with my tower down. (I put it up today.) I think I'd
rather look for an alternative product or revisit the HAMM which I still
have.

| Dan,
|
| Since you live so close to the ocean, you might want to try and coat (spray
| paint) the rotator assy with NEOPRENE PAINT. (This paint is waterproof &
| impervious to salt water & diesel fuel and you should be able to find it in
| either a well stocked hardware store or paint supply store).

I'm not sure how this would help in more than a cosmetic way. You understand
that the rotor is not sealed, right? There is a gap between the bottom of
the bell and the mounting plate. It points down so water shouldn't be
*flowing* in, but the insides are certainly exposed to the weather. The
only thing keeping the bearings from rusting is the grease, and the retainer
strip really can't insure that they are always fully coated. The more I
think about this the more I remember stainless bearings in the HAMM, though
it might have been an after-market modification.

| You also might want to coat any open antenna connectors as well as any
| coaxial connectors.

I've had good luck with a tight spiral wrap of ordinary vinyl tape. Just
took apart some connectors that had been up for more than a decade and
they were shiny as new. Lately I've also been filling the insides with
STUFF dielectric paste but I'm not sure this makes much difference.

Dan Lanciani
ddl@danlan.*com

Dan,
There's no 'fool proof' way of 'fixing' any rotor that doesn't mean
a lot of inconvenience in some way. Picking the most palatable
inconvenience is the 'trick'.
"Productive"? Uh, yeah, I agree with you, probably not very
productive, But I'd do that complaining anyway. Who knows, they
might really surprise you (and me ).
Which solution is the best? I have no idea.
- 'Doc

Beat the @#$ thing to death with a very large hammer. Productive?
No, but @#$ sure satisfying!

Howdy,

In the 70's I worked on a project developing dual use small
boat radar. We had a terrible time with bearing corrosion at
first.

You might want to try wash-out resistant grease intended for
boat trailer wheel hubs.

In the radar we eventually used Andok C which is no longer
manufactured. Nye developed Rheolube 374C as a replacement
for Andok C. Both are an NLGI Grade 4 grease,

McMaster-Carr has a good selection of stainless steel bearings
and they have ceramic balls for bearings I believe. I'd want
to play with those a bit first before putting them up on a
tower.


73,
Grumpy



ddl@danlan.*com (Dan Lanciani) wrote in
:

I've had good luck with a tight spiral wrap of ordinary vinyl tape.
Just took apart some connectors that had been up for more than a
decade and they were shiny as new. Lately I've also been filling the
insides with STUFF dielectric paste but I'm not sure this makes much
difference.

Dan Lanciani
ddl@danlan.*com

"Grumpy The Mule" wrote in message
...
Howdy,

In the 70's I worked on a project developing dual use small
boat radar. We had a terrible time with bearing corrosion at
first.

You might want to try wash-out resistant grease intended for
boat trailer wheel hubs.

Good advice.

McMaster-Carr has a good selection of stainless steel bearings
and they have ceramic balls for bearings I believe. I'd want
to play with those a bit first before putting them up on a
tower.

Most folks instantly think of stainless steels for corrosion protection.
However SS is not a particularly corrosion resistant material around salt
water. All commonly available grades of SS are subject to halogen
corrosion, i.e. chlorides in sea water. Before retirement I worked at
Eastman Chemical company in their research laboratories. They frequently
had to resort to rather exotic alloys, such as Hastelloy C-276, for
applications where halogens were involved. These alloys tend to be
extremely expensive and nearly impossible to machine.

I would suggest using lots of a good grease and frequent maintenance if your
rotor is exposed to salt air.

Barry WA4VZQ