Some years ago I did simple, non-scientific test comparing sugar wraps
(preforms), 3 cable clamps, and the 3 hole plates that the power company
used to use....
A tree stump and a tractor were involved.
The 3 hole press plates ( I have no idea what they are really called)
have a slot in them for the cable - and the cable was intially used in
them so the size was right. No amount of tightening the bolts caused any
significant load on the tractor. The guy wire slipped thru very easily.
So much for them - I had a 5 gallon pail full so wanted to see if they
were any good.
Next up was the traditional 3 cable clamps (Crosby clips), spaced properly
for the cable thickness (6 times 5/16 I think). They did better and if a
person could re-tighten after the initial pull they might have held.
Last was the "new to me"and "I can't believe it works" sugar wraps. As I
later found out I installed this quite incorrectly - almost no grit left
on the wrap - had been used many times and was slightly oversized for the
wire - the wraps showed no space between them when installed, - a BAD
combination. Yet it held the tractor solidly, nothing slipped at all -
those few thin strands didn't break at all.
I have seen the press fittings but have no experience with them.
What force was involved?? I don't know. A 50 hp tractor, pulling slightly
downhill, on dry sod (it quickly dug down a foot or so) can pull quite a
bit and I felt it was a much greater force than anything that would be
exerted on single guy wire. I slept easier having done that simple test
years ago........never did get the stump out, though!
73 Don
VE6JY is Don Moman email: ve6jy@freenet.edmonton.ab.ca
Box 127 Lamont, Alberta
T0B 2R0 (403) 895-2925
On Tue, 8 Apr 1997 00tlzivney@bsuvc.bsu.edu wrote:
> WE9V's comment about the failure of professionally installed nicopress
> fitting brings forth the following thought - How do we KNOW (proof test)
> the installed strength of our particular connections? I don't use
<etc>
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