In article . com,
Jack wrote:
Does anyone use ferrules(sp) on cable? I need to make some straps out
of 3/64 cable, they will not carry heavy loads, just span a gym and
paper stars will be hung from them.
The ferrules are known as nico-press sleeves.
If you are hanging anything overhead, even just the cable itself, you
need to use the correct fittings, either nico-press, crimped with the
proper tool, and tested with a go/no-go gauge, or a Crosby clip (U-bolt).
If you are unsure of how to properly install nico-press fittings, or lack
the proper tool to do so, you must use Crosby's instead.
There is NO safe way of installing nico-press sleeves without a proper
crimp tool.
Can I use ferrules if I just crimp them "Detroit Style" by pounding on
them with a hammer?
NO.
How about smashing them in my bench vice?
NO.
I have seen the tools specifically for the job but they are way to
expensive.
There are two styles of tool for nico-press sleeves:
One type looks like a pair of bolt cutters, and will cost a couple hundred
bucks.. (I haven't priced them recently). This is the type you get if you
are going to be installing them regularly.
The other type is much simpler, but very slow.. it is basicly a two piece
clamp with bolts that you tighten down to make each crimp.
Check with your local theatre companies, they may have a tool that they
will let you use, and they may even help you make the cables, and help
with the initial installation. Ask nicely.
Another place to check would be a marine supplier, or an industrial rigging
company..
Do I really need to use thimbles, or can I just make loops.
Yes, you must use thimbles to avoid exceeding the minimum bend radius of
the cable, which can lead to kinking, and loss of strength in the cable.
If you are just using the cables to lock things up, you can get away without
the thimbles, but if you are using them for overhead rigging, you must use
them.
(I want to use cable because we decorate the gym frequently and it
would be nice to just have a set that we can string up, rather than
re-invent the wheel every time and start tying rope, and trying to keep
them from stretching... etc. )
Remember that you may not always be there, and that somebody in the future
may decide to try and hang something heavier than paper stars on the cable,
so do it right the first time.
The last thing you want is for a mirror ball to come crashing down on
somebodys head in the middle of a dance.
Any thoughts?
If you are going to use nico-press sleeves, there are several very important
things to consider:
1. you MUST use the correct size sleeve for the cable. there is zero margin
for error. do not use 1/4" sleeves on 3/16" cable.
2. you should crimp each sleeve in at least two locations. (I normally do 3).
srart at the thimble, and work out.
3. remember that the sleeve will expand lengthwise when crimped, so if you
trim the cable to just barely peek out from the end of the sleeve,
you should end up with the cable end flush with the sleeve when you
are done.
4. Test each crimp using a go/no-go gauge.
If you are using Crosby clips instead of nico-press sleeves, remember that
the U-bolt ALWAYS goes on the dead (cut) end of the cable. Do not stagger
the clips.
When using Crosby's, always leave a couple inches of tail, but feel free to
tape it down after you have installed the last Crosby.
Remember the rule: "Never saddle a dead horse"
Helpful tips.
When cutting cable, if you wrap the cable with tape (electrical tape, or
masking tape work well), and cut thru the middle of the tape, the ends don't
fray. This is important because it is hard to get frayed cable into the
sleeve.
Always cut your cable slightly longer than you need. Install the nico-press
or Crosby's on one end, re-measure, and then make your final cut.
Make sure your anchor points are solid.
Make sure your anchor points are solid.
You can alys install turnbuckles if you need to tension the cable, in which
case you want to make the cable slightly shorter by the length of a turnbuckle.
measure the turnbuckle when it is set at it's mid point.
turnbuckles should be rated for load, and connected using rated shackles
or quick-links.
make sure the cables are properly stored, and are not kinked in the process.
I have visions of volunteers wrapping cables over their elbows in the manner
that destroys many an extention cord...
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