More than three crimps on 1/4" aircraft cable

slim1357

Member
I keep running across wire rope terminations that have been made with 4 crimps instead of 3. I am well aware that 3 crimps is what is prescribed for nicopress copper sleeves but loos and co. say 4 crimps for their sleeves. Is there any difference between loos and co. sleeves and nicopress sleeves that would explain this? They appear identical to the naked eye. I am probably going to replace the pick lines that have 4 crimps just because I can and I have anecdotal evidence that the crimps were made with a cheapo Chinese swager. Just curious what other rigger's opinions on the subject are.
 
From the thread http://www.controlbooth.com/forums/scenery-props-rigging/22238-locoloc-v-nicopress-swage-tools.html :
As several have pointed out, and the load lab tests by Delbert Hall seem to verify, mixing brands of sleeves and tools does not seem to make a difference. However, if you are an installer, don't mix. Your insurance company and their lawyers will agree. The reason is no manufacturer will guarantee another manufacturers product. So, if you mix, and there is a failure, all the manufacturers will claim it is the other companies product that was responsible. The result will be that, you, as the installer who did not follow the instructions with the tool or the sleeve not to mix, are at fault because you mixed products.
Delbert's website, with the results of the load tests referenced above, appears to be going through a renovation at the moment.:(

See also the threads http://www.controlbooth.com/forums/scenery-props-rigging/26915-aircraft-cable-use-swages.html and http://www.controlbooth.com/forums/scenery-props-rigging/26433-nicropress-crimp-size.html .

Bottom line answer:
Number of crimps = whatever the manufacturer specifies, for the size of cable and specific model of the tool and swage sleeve.

If that's (for 1/4" GAC) three for Nico but four for Loos, even though the swage sleeves are virtually identical and interchangeable, then so be it.

EDIT: This may better answer your question:
... Sometimes you can look at the crimp and tell what tool was used. For instance the Loco-Lok hand tool has a really narrow jaw, which is why 4 crimps are required. ...
 
Last edited:
Thank you. Some more googling and inspecting the suspect (4 crimp) terminations makes it clear that the tool used has a much narrower jaw than the nicopress tool. I know from a discussion with the installer that they used loos and co. copper sleeves and a nicopress swaging tool to make the compressions on the majority of the terminations during the install. All of those have 3 compressions and despite many failing a go/no-go (we are re squeezing them) they appear OK. I am replacing lines on my fly system and fortunately I was able to convince the muckity mucks that using all nicopress tools and sleeves was the smart way to go.
 
Updates to this thread:
Nicopress Technical Bulletins

Efficiency of Wire Rope Connections
(Download)
Nicopress Theatrical Industry Product Brochure https://www.nicopress.com/documents...chure_Theatrical_Rigging_Connectors_Tools.pdf

Comparison of Aluminum and Copper Compression Sleeve Materials Used for Terminating and Splicing Wire Rope https://www.nicopress.com/resources/technical-info.aspx
(Request for literature to be sent)

The following items are normally here (https://www.nicopress.com/resources/technical-info.aspx), but the link is temporarily broken, so I have attached the documents.
· TB 1.0: Proper Press Sequences, Wire Rope End Protrusion, and Thimble Clearance for Oval Sleeve Eye Splices
· TB-2.0: Go-Gauge or Go-No-Go Gauge
· TB-3.2: Proper Material Selection for Wire Rope Sleeves
· TB-4.0: Proper Construction of Eye Splices & Lap Splices Using Multiple Compression Sleeves
 

Attachments

  • Nicopress Tech Bulletin 1.0 - Number of Crimps.pdf
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  • Nicopress Tech Bulletin 2.0 - Go-No-Go Gauge.pdf
    178.6 KB · Views: 351
  • Nicopress Tech Bulletin 3.2 - Crimp Sleeve Materials.pdf
    272.1 KB · Views: 561
  • Nicopress Tech Bulletin 4.0 - Eye and Lap Splices.pdf
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