I might check with Hubbell/Chance regarding the use of their fiberglass guy
strains on a rotating tower if the devices in the link below are what you
are planning to use.
https://www.hubbell.com/hubbellpowersystems/en/Products/Power-Utilities/Line-Construction-Hardware/Guy-Strains/c/561514
Those guy strains look very robust, but I would suggest they are designed
to be used for static guy wires that only see lateral stress at the clevis
fitting primarily as a result of aeolian vibration. When a rotating tower
starts to move, I would expect there is a more significant lateral load on
the fiberglass junction at the crimped/glued clevis fitting. The repetitive
lateral force that may occur at that junction every time the tower rotates
is of concern to me. The fiberglass fibers in the rod are super strong in
linear tensile loading, but my suspicion is the fibers do not do as well in
lateral bending.
I do not claim to be an expert and hate to pour cold water on your plans.
If you feel you want to insulate the Philly Big Grip from the K0XG torque
arm, the DXE Bent Pin Clevis is likely a reasonable option. I, too, have a
K0XG rotating tower and have plans to replace the fiberglass polygon rod
guys. My reason is more related to the fact that I can visibly see
UV/weather effects on the polygon rod which has me concerned. It appears
Hubbell has those guy strains available with a silicone coating, which you
may want to consider if you opt to use them. I bit the bullet and
purchased the Bent Pin Shackles and new Philly a while back in
anticipation of the planned work ahead at my station.
GL/73
Mark WH7W/WH7T
On Sun, Oct 16, 2022 at 4:22 AM <john@kk9a.com> wrote:
> I would have cut the guys off the rings when dismantling the tower to
> insure
> that the Phillystran was not damaged. I believe your tower was originally
> in
> Florida and you're in Ohio. Depending on the frequency of the antenna(s)
> near the rotating ring, insulators may or may not be helpful. Just cut off
> a
> few feet of Phillystran and install new grips on previously un-gripped
> cable, I have done this myself without issue. I had to frequently replace
> the Big Grips at my P40A station due to corrosion and I have also done it
> when moving a tower. Compared to all of the other costs with your project,
> $350 for Big Grips is very minor.
>
> GL
> John KK9A
>
>
>
> James w8wts wrote:
>
> I wish that I could use shackles to fix this problem. The original builder
> of these guy wire assemblies (NOT me) threaded the loop of the PS big grip
> through the hole of a K0XG guy ring torque arm with a thimble. The PS big
> grip and the rest of the tower were electrically connected. In my new
> build, I am installing an insulator between the torque arm and the PS big
> grip. Obviously the only way to insert an insulator is to remove the
> present PS big grip. I am not happy about disposing of $350 worth of PS
> big
> grips, but I'm willing to eat that cost to have insulators between the
> torque arms and the PS big grips. I have Hubbell fiberglass rod down guy
> insulators to attach the torque arms to the new PS big grips with thimbles.
>
>
> That is why I wondered if I could wrap new PS big grips over the same
> length
> of PS that used to be under the old big grips. I certainly could just snip
> off the old big grips and the three feet of Phillystran under the big grips
> on every end and start over, making the EHS tails about 3 ft longer. I
> would end up throwing away over 36 ft of Phillystran, which I am loath to
> do.
>
> I will not try to reuse PS big grips in any way. I only wonder if I can
> put
> new big grips on the same length of PS that had a big grip installed there
> once before. I have not checked to see if the polyurethane jacket and the
> aramid fiber core have sheared apart at the end, but will do so.
>
> I appreciate everyone's input.
>
> 73,
>
> Jim, W8WTS
>
> _______________________________________________
>
>
>
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