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I have used a crank up for 30 years now and have been involved with =
several other installs. The main reasons for crank ups to fail are:
1. wire rope starts to get snags and lose strength. See a snag replace =
the rope.
2. Rohn crank ups had problems with the rope coming off the pulley. =
Always make sure pulleys are oiled and working.
3. The clamp breaks under tension. Make sure each clamp is secure. many =
of the clamp machines used for boating only hold well for horizontal =
loads. A crank up is a cervical load. Get it done at a foundry or at a =
manufacturer. If all else fails use wire rope clamps. My lower section =
is held by 4 wire rope clamps.
4. The winch (manual or motor) freezes up.
Overkill in winch, clamps, and rope size are just more insurance.
Dave K4JRB
=20
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<DIV><FONT color=3D#000000 face=3D"Courier New">I have used a crank up =
for 30 years=20
now and have been involved with several other installs. The main =
reasons=20
for crank ups to fail are:</FONT></DIV>
<DIV><FONT color=3D#000000 face=3D"Courier New"></FONT> </DIV>
<DIV><FONT color=3D#000000 face=3D"Courier New">1. wire rope =
starts to get=20
snags and lose strength. See a snag replace the rope.</FONT></DIV>
<DIV><FONT color=3D#000000 face=3D"Courier New"></FONT> </DIV>
<DIV><FONT color=3D#000000 face=3D"Courier New">2. Rohn crank ups =
had problems=20
with the rope coming off the pulley. Always make sure pulleys are =
oiled=20
and working.</FONT></DIV>
<DIV><FONT color=3D#000000 face=3D"Courier New"></FONT> </DIV>
<DIV><FONT color=3D#000000 face=3D"Courier New">3. The clamp =
breaks under=20
tension. Make sure each clamp is secure. many of the clamp machines used =
for=20
boating only hold well for horizontal loads. A crank up is a =
cervical=20
load. Get it done at a foundry or at a manufacturer. If all else =
fails use=20
wire rope clamps. My lower section is held by 4 wire rope =
clamps.</FONT></DIV>
<DIV><FONT color=3D#000000 face=3D"Courier New"></FONT> </DIV>
<DIV><FONT face=3D"Courier New">4. The winch (manual or motor) =
freezes=20
up.</FONT></DIV>
<DIV><FONT face=3D"Courier New"></FONT> </DIV>
<DIV><FONT face=3D"Courier New">Overkill in winch, clamps, and rope size =
are just=20
more insurance.</FONT></DIV>
<DIV><FONT face=3D"Courier New"></FONT> </DIV>
<DIV><FONT face=3D"Courier New">Dave K4JRB</FONT></DIV>
<DIV><FONT color=3D#000000 face=3D"Courier New"></FONT> </DIV>
<DIV><FONT color=3D#000000 face=3D"Courier New"> =
</FONT></DIV></BODY></HTML>
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