[TowerTalk] Kellems Grips---A Reprise
Larry McDavid
lmcdavid@lmceng.com
Sun, 10 Aug 1997 00:36:42 -0700
There were many responses and some additional questions resulting from
my previous post, "Kellems. . . All You Ever Wanted." Since there
appears to be considerable remaining interest, I'll answer the questions
and clearify some issues here.
1. For all those who wrote to share their good experiences with Kellems
grips: I congratulate you on striving for excellence and I hope you
will share your thoughts with more amateur friends.
2. For all those who wrote to further the use of black tie wraps, tape
and scrap pieces of wire: I congratulate you on your successes and
satisfaction in "doing it your way."
On the advancement of coathanger wire cum Phillystran coax-grip: I'm
willing to be convinced, but I'm hopeful this concept was advanced some
four months late . . . . .
3. While I did list some specific coax types in my earlier posting, this
really was to identify the RG-8 style size and the corresponding Kellems
grip to fit it. Not all coax is suitable for hanging free from one end
alongside a self-suppoting tower. In particular, type 9096 (and similar
types with open spiral dielectric) which offers the combined
characteristics of garden hose and silly putty, is not a good candidate
for free hanging by Kellems or any other means.
4. I've never used any RG-8X so I cannot speak for hanging it free from
one end. It is specified to be 0.242-inch diameter, so a Kellems grip
P/N 02216001 with a range of 0.23-0.31 should work.
5. I could be proved wrong, but I believe it is impossible to install a
Kellems grip using only one hand. If you're holding onto the tower with
the other hand, there is a bigger problem here than how you hang your
coax.
6. In my posting I did suggest that the Kellems grip be installed before
the coax connector. Let me amplify this: you *must* install the
closed-mesh Kellems grip before the PL-259 is installed. Else, your
friends and neighbors will not consider you acceptable company for some
time to come.
There are "split-mesh, lace closing" and "split-mesh, rod closing"
Kellems grips available if you must install the grip after the coax is
attached. If you want to pursue this, you really need to get a Kellems
catalog to appreciate what is available. These items are more expensive.
7. In response to several individuals who asked about the use of more
than one coax cable in a single Kellems grip, I discovered a table in
the technical data section of the catalog which identifies the correct
grip size to be used when multiple cables of the same diameter are to be
installed in the single grip. Assuming all the coaxes are RG-8 type with
about 0.410 diameter, the following are recommended:
No. of Cables Grip Dia. Range P/N
1 0.38-0.44 inch 02216003
2 0.62-0.74 02217008
3 0.75-0.99 02217010
4 1.00-1.24 02217014
I have not priced these larger grips so I cannot judge whether they are
cost effective over multiple small grips.
I have deliberatly identified the "Heavy Duty" style Service Drop grip
for the 2, 3, and 4 cable cases while continuing to use the "Light Duty"
style for the one-cable case. The light duty grips should be ok as well
and will cost less than the heavy duty models. Widely-varying cable
diameters within a single grip are not recommended. I believe that coax
and a heavy-duty rotor cable would be usable in a single grip.
8. Installations I am familiar with all use a Kellems grip or grips at
the top only of the unguyed tower and the full length of coaxes hang
down from that. In a tall guyed tower, I think I would put one grip at
the top and possibly another one near the middle of the tower height;
and, yes, in this case, I would tape the coax to one tower leg every
five or ten feet. But, this second grip is really not needed.
Truth is, in an unguyed tower with free-hanging coax bundle, I prefer to
include in the bundle a fairly large size UV-resistant rope; I tension
this to reduce cable flop. This rope, however, invariable stretches more
than the coax and does not support the weight of the coax.
Friends, in these two rather long postings I have barely scratched the
surface of the info in the Hubbell or Kellems catalogs. If you are
serious about these grips, you should really try to get one of these
catalogs. I suggest you just go buy one of the Kellems 02216003 grips to
fit a single RG-8 size coax and see for yourself if you like it. This
would be $6.45 well-spent from which you can form your own opinion.
Again, I'm not selling or promoting anything. But I enjoy a job well
done and I believe Kellems grips do their job well.
Best wishes and happy climbing to all,
Larry McDavid W6FUB
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