Not quite sure which I should reply to, but I'll go with this one.
jim Jarvis wrote:
> Crazyhorse:
>
> Interesting pic. I've SEEN this before, somewhere, but I'm not
> bringing up a name.
>
I've seen a number of aluminum towers like this but no steel.
> Recommend you re-post to the reflector, with a link to that pic.
> Someone will know what it is.
>
> Guys: Crazy has what seems to be a 25g knockoff, which uses external
> sleeves to join
> sections, rather than swaging. Sleeves are welded to the tower
> legs, such that the bottom
>
That does complicate the fit as there is little of no give in this type
of connection leaving the bolts doing more of the work than they would
in a 25 or 45G
> of each section fits over the top of the one below. (except in his
> case, they don't fit very well.)
> Anybody know who might have made this? It has cross bracing design
> like 25g.
>
>
I'm assuming from the description and photo that it's also about the
same size as a 25G with the same leg spacing.
> Back to the original problem... you're trying to assemble some stuff
> that won't go
> together. Suggest we focus on that.
>
> There are two basic problems, crud in the sleeves, and mis-alignment
> of legs.
> To separate the two, you could use a piece of leg, and test-fit it
> in each sleeve.
> If there's only dirt and gunk in there, the tube may be enough to
> clean things out.
>
I'd get one of those wire brushes that fit a drill motor or high speed
grinder to clean the crud out of the legs. They look much like the brass
brush used for cleaning shotgun barrels. "Typically" they do a good
job of "de-crudding"
> If not, a rat-tail file gently applied around the inner part of the
> sleeve should clean it
> out enough to allow the tube to fit.
>
I'm not a fan of files on towers as they can dig pretty deep leaving
scratches that are a breeding ground for rust and it's difficult to get
much in the way of uniformity.
In addition to the wire brush, there is the old trick we used to "port
and polish" engine heads. We'd take a 1/4" or 3/8" rod, cut a slot
about 3" long, cross wise and insert a strip of emery cloth. Using the
coarser grades it can get pretty aggressive, but does a much more
uniform job than the file. Those coarser grades also make removing crud
a quick job and leave a pretty nice finish. If it needs to be smoothed
a shot of 200 grit will leave it shinny. Of course if you are a purist
600 grade will leave a chrome like finish<:-)) (You just stick the
emery cloth through the slot with about equal lengths on each side. You
turn the rod slowly, wrapping the emery cloth around it with the
abrasive side out.
> Then there's leg alignment. Once you know that each sleeve is
> clean, legs can
> sometimes be bent slightly out of column. A tower-jack multipurpose
> tool has a
> leg-straightening fixture on it. Or, you can use that short piece
> of leg as a lever to
>
Unless actually bent I don't see leg alignment as being much of a
problem. I've seen legs out by as much as 3/8" on 45 Gs which created no
problems. With the new section suspended above the existing sections, I
let it down to the point where two legs match and just slide together
slightly while the third rests on top of the lower leg. There is enough
spring that I can easily pull the leg into alignment with one hand and
it will drop into place. Releasing the tension on the support cable has
always resulted in the section sliding all the way to the shoulder.
> pull an errant leg in or out, appropriately. It would pay to test-
> fit all sections, on the
> ground, rather than discover a mis-alignment in the air, and have to
> wrestle with it
> aloft.
>
A tower the size of 25 G would have less tolerance of a leg being out
than one of 45 G size, but as I said above, I've never had one that
created a problem "up there". BUT a bent leg would be an entirely
different matter. This can be checked on the ground (preferably
driveway or any flat surface). Lay two sections end-to-end and slip the
two best fitting legs together. Now look at the third. Can it easily be
sprung into place? I'm not talking about actually putting the sections
together here, just whether they can be matched up. If they can with a
one hand pull even if it takes a hefty one hand pull they should be good
to go, but that indicates all sections should be checked. Normally the
sections are a lot easier to slip together "up there" than "down here"
unless the legs are really out.
If they are out only enough to be annoying or even add a little work,
I'd leave them alone. Don't bend anything on a tower unless you really
have to. Every bend that is enough to change the shape permanently
represents some degree of weakening. Bending it back is another bend and
further reduces the strength to some degree. So, if it can be sprung
over by hand I'd call that a better way to go.
The bolts *appear* to be "centered" or pointed at the center of the
tower in the photo so unlike some Aluminum towers I've seen it
*probably* won't matter as to leg orientation.
> Don't forget to use grease on all legs, before assembly. Not only
> improves things
> going in--they come OUT a whole lot easier, when the tower gets taken
> down.
>
I never grease tower sections. Most are designed for the legs to grip
which reduces the load on the bolts. Lubricating the joints also
increases the tendency of the tower sections to move or pivot slightly
at the joints in strong winds, eventually resulting in elongated bolt
holes. I've taken some apart where the bolt holes were greater than 50%
over size. This seems to be endemic with aluminum towers.
> It MAY be old grease in those sleeves, too. In which case, use of a
> leg piece or similar
> pipe will clean things out.
>
I'd use the round, wire brush and solvent if necessary to clean out
those joints.
73 and good luck,
Roger (K8RI)
Roger (K8RI)
> N2EA
>
>
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