We have erected five towers at K5XI using HPTG6700 Phillystran. The 100',
110' and 140' use the old potted heads. The new 200' and 250' use the new
stuff with four cable clamps (the riggers call them "crosby's). They work
great! According to the manufacturer, they have made the vynil jacket
sufficiently thick to withstand the compression and hold tension without
deforming the strands. I removed the clamps from a piece after about 24
hours and there appeared to be no permanent deformation.
We havent noticed any stretching. Each guy is tensioned to 600 lbs using a
series dynamometer. If you are using the "it feels tight" method, you
aren't tightening them enough. Don't forget, use about 3' of steel cable
at the top of the tower, in case someone drops a tool or antenna. Use 15'
to 20' of steel cable at the ground in case of fire or vandalism.
73 and DX,