I replaced my original galvanized cable with 7x19 SS wire cable on my
HG70-HD some time back. I live on the ocean. The original cable was from
1982 (installed at the beach in 2003).
The change to SS was at the suggestion of the local fleet rigger in
Newport OR based on years of use. It has a higher wire strand count thus
is more flexible. I've never had to replace any sheaves. all are still
in good condx. I replied heavily on this rigger's long experience with
making up cable assemblies and installing both galvanized and SS wire
cable and rope on small and large fishing vessels operating out of the
port. He also referred me to this site which I imagine is available in
different write-ups at many cable manufacturers -
https://bergencable.com/cable-101
Because of cost most of the fleet vessels use galvanized cable and the
use of SS seems to be reserved to special requirements and needs
The rigger calculated the 4 key items (load, sheave sizes, bending
factors, and possible distortion) to determine if the properly sized SS
cable I was looking at would have a sufficient safety factor. It did.
BUT, there was a significant cost over galvanized cable.
Just more input on the SS vs galvanized cable discussion.
Don W7WLL
On 6/29/2020 11:44 AM, Grant Saviers wrote:
Another reason besides what Steve mentions is SS cable isn't as strong
as hoist wire rope, where are many more choices of construction and
alloys.
My read of the PE wet stamp for my HDX 589 causes me to believe that
it has a below recommended man-lift safety factor when considering the
strength degradation from small diameter sheave wraps (ie smaller than
what Crosby recommends). So better proceed with some expert analysis
in hand before making a substitution.
Or apply Rule #1 - Do what the manufacturer recommends.
Grant KZ1W
On 6/29/2020 11:05, Steve Maki wrote:
For crankup towers? Seems like it should be OK, I'd check with the
tower manufacturer. I think of crankup tower duty as similar to crane
service in that the cable is mostly stressed by the wrap around the
sheaves. So if the bending properties of SS is as good as regular
cable, it should be fine. But I don't know that it is.
You never see SS cable on cranes, probably because it's more
expensive, and the crane companies keep their cable lubed religiously
for corrosion and abrasion protection. Yet they still have to replace
it every so often due to wear, which would apply to SS cable just the
same.
Steve K8LX
On 06/29/20 12:29 PM, Edward via TowerTalk wrote:
Is it smart to use SS aircraft cable in place of the factory
galvanized cable?
I'm guessing you are talking about SS "aircraft" cable, right?
Bolt cutters don't work on finely stranded cable because. For that
you need either cutters meant for the job, or a cutoff wheel on a
grinder. Cutters for aircraft cable are generally bypass type
shears with both sides curved.
If it's 1x7 strand, bolt cutters work, or a cutoff wheel, or cable
cutters meant for the job, which are usually bypass type shears
with one curved side and one straight.
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