Swaging ferrules - after-swage dimensions

[stickshift]

I'm swaging aluminum ferrules onto 3/16" 7x19 wire rope. Ferrules I'm using.

Per these instructions at US Rigging Supply, 3/16" aluminum sleeves should be crimped 4x and the maximum after-swage dimension should be 0.475". I borrowed a friend's swager (looks to be a $20 18" swager found at big box stores) and the swages are measuring 0.480 - 0.485". I don't have a go/no-go gauge, so I'm using digital calipers, and I assume the correct place to measure is across the widest part of the crimp?

US Rigging's 0.475" after-swage dimension is supposed to yield 90% of the breaking strength of the wire rope. The 3/16" wire rope itself has a working load limit of 840lbs (which itself I assume is some fraction of the breaking strength). I'll be using loads of less than 200lbs. Any thoughts on whether being 0.01" over spec is good enough?

The swager looks pretty old and had some rust on it, so I assume it's been worn down a bit. If I buy a new swager, can I re-swage these ferrules to try to get down to spec, or should I start over with fresh ferrules?

 

[Strouty]

The way you test the tool is by putting your finger in it and squeezing, if you only see blood it is not working properly, if you see blood and hear a crunching noise, it is working correctly.

If I were in this situation, I would proof test it, where you are using such a small portion of the capacity, you should be fine.

 

[Strouty]

What are the dimensions of the compressed part? Are they between 0.465 and 0.475?

It seems to me that it would be measured where you compressed, maybe measure the die opening when it is completely closed and see what that is.

 

[T45]

OP - I think if people want to chime in on some best practices fine, but you need to be responsible for your end result with this situation.

 

[2oolhound]

Can you line the inside of the swager with some thin shim packing. You're almost there.
When I was rigging in the 70's safe working load was 1/5 of the breaking strength. Pressed ferrules were just making their debut and were all done hydraulically at the supplier so I'm not too up to snuff with this technology but I'd make sure it was to spec. You never know who uses the sling down the road.

 

[woody 73]

Stickshift give them a call at 1-888-260-7444 and they will put you through to a technician that can answer your questions, better to be on the safe side.

http://usrigging.com/

 

[stickshift]

What are the dimensions of the compressed part? Are they between 0.465 and 0.475?

It seems to me that it would be measured where you compressed, maybe measure the die opening when it is completely closed and see what that is.

I'm placing the widest part of the oval ferrule perpendicular to the swager. Then I'm measuring across what was the widest part of the uncompressed oval.



I was getting 0.480 - 0.485", but per US Rigging Supply (http://www.usrigging.com/pdfs/Swage-Inst.pdf), it should measure 0.465 - 0.475".

Good idea on measuring the die opening. Interestingly, the largest measure I got for the die opening is 0.435. There is a bit of play in the swager that prevents the dies from fully closing when there is a sleeve + cable in the die. Seeing that, I snugged up the bolts on the swager a little bit and re-swaged the ferrules and now I've gotten the crimps down to 0.475 - 0.480", so very close to the 0.475 spec for max post-swage dimension.

Can you line the inside of the swager with some thin shim packing. You're almost there.

What kind of material would you suggest for a shim?

 

[Strouty]

I figured the die would be smaller, the metal is hard to squish without some rebound. I don't do many of these types of connections, I usually do what is called a flemish eye and then use crosby style clamps, but I also have to take them apart later, so a crimp is not good for me.

You could proof test it by picking at least two times the load you are going to use.

 

[stickshift]

Stickshift give them a call at 1-888-260-7444 and they will put you through to a technician that can answer your questions, better to be on the safe side.

http://usrigging.com/

Thanks. Just gave them a ring. He couldn't really say what % efficiency I'd get as I move away from the 0.475" spec. He also noted that this spec is for the milspec sleeves that companies like US Rigging and Nicopress manufacture and that not all sleeves are dimensionally identical. I got the sleeves from Home Depot, so they are probably made in China, so even if they are designed to match the milspec, there may be some variance.

One thing he pointed out was that you should crimp sequentially, one crimp adjacent to the next, to help spread the metal out. What I did was crimp at each end and then place two more crimps in the middle. So I'll redo these the way he suggested. That might influence the crimp dimension by just enough to get these crimps in spec.

 

[rlitman]

... There is a bit of play in the swager that prevents the dies from fully closing when there is a sleeve + cable in the die. Seeing that, I snugged up the bolts on the swager a little bit and re-swaged the ferrules and now I've gotten the crimps down to 0.475 - 0.480", so very close to the 0.475 spec for max post-swage dimension.

What kind of material would you suggest for a shim?

You're right, in that tightening the bolts is the way to go. I'd remove the bolts, put a thin coating of grease on everything, and re-install. That should help too. It's like adjusting bolt cutters to close the gap.

...One thing he pointed out was that you should crimp sequentially, one crimp adjacent to the next, to help spread the metal out. What I did was crimp at each end and then place two more crimps in the middle. So I'll redo these the way he suggested. That might influence the crimp dimension by just enough to get these crimps in spec.

I'm not sure it would influence the crimp dimension, but it would influence the pull strength of the swage. Each crimp stretches the wire under it just a little. Crimping the outer two first loosens the wire inside the ferrule between the two crimps. Enough that in the end, all four crimps will not be carrying the load evenly, so you might reduce the strength of the swage by half.

 

[2oolhound]

If it comes to shimming your tool anything harder than the sweges will do. A good source though is an old feeler gage.

 

[shawhite]

Curious are you braiding the eye first then using the swages.

 

[Strouty]

I am pretty sure that style crimp is not for back braiding the cable.

 

[shawhite]

Not sure if it is correct but that is how we do our winch lines at work. Slide the swage on braid the eye then slide the swage in place and crimp. Old timers swear it holds better. We have never had one come loose.

 

[Strouty]

That style crimp is designed for what they call "turn back splicing", the flemish eye is when you back splice and it requires a different style crimp.

https://www.thecrosbygroup.com/wp-c...92320_Termination_Manual_With_Cover_LoRes.pdf

 

[stickshift]

Curious are you braiding the eye first then using the swages.

Not sure what "braiding the eye" means, I'm just taking taking the cable, sliding the sleeve on, wrapping the cable around a thimble and threading the cable through the second hole in the sleeve, then swaging.

 

[2oolhound]

At one time all eyes were spiced which was a slow arduous job.
Then cups were made and zinc ferrules were poured into them.
Then came the pressed ferrules done in factory with a tremendous amount of force and said to be the strongest to date.
Now we have the homeowner or on the job type like what we see here.
Cable clamps we used to form eyes also but they were messy and require a lot of room.
A very simple splice called a Molly Hogan which is a very weak splice could also be used with these ferrules because it doesn't change the size of the cable past the eye. It should add some strength as well.

 

[no704]

I like to end up with the end of the wire slightly inside the swage, I hate getting stabbed by those cable ends!

 

[shawhite]

A very simple splice called a Molly Hogan which is a very weak splice could also be used with these ferrules because it doesn't change the size of the cable past the eye. It should add some strength as well.

That's what I was referring to when I said splicing the eye. Did not know the name of it but looked it up and that is how we always do our eye splices.

 

[Strouty]

Splicing/back braiding/flemish eyes are really easy to do on wire. Splicing an eye in rope is tougher, especially double braided rope.

It appears that they get a bad name because some people won't use any sort of backer and I don't mean tape. They should have clamps or crimps if you are using them for anything more than a dog run or curtains.

 

[stickshift]

You're right, in that tightening the bolts is the way to go. I'd remove the bolts, put a thin coating of grease on everything, and re-install. That should help too. It's like adjusting bolt cutters to close the gap.



I'm not sure it would influence the crimp dimension, but it would influence the pull strength of the swage. Each crimp stretches the wire under it just a little. Crimping the outer two first loosens the wire inside the ferrule between the two crimps. Enough that in the end, all four crimps will not be carrying the load evenly, so you might reduce the strength of the swage by half.

Thanks for the explanation.

I went ahead and cut off the eye loops, and redid them using new ferrules. I crimped sequentially this time, and had to compress each crimp 2 or 3 times to get it within or very close to spec, then made the next crimp adjacent to that.

Over 4 sleeves (16 crimps in total), the range of post-swage dimensions was 0.473" - 0.477". Should be good, and I will load test this with a load greater than any regular use load. I'll also make witness marks on the cable so that I can see if there is any slippage over time.

Thanks everyone for the info and advice.

 

[hogdaddy]

What is the intended use of the wire rope?
We use generally use copper ferrules (Nicopress) over aluminum.

http://www.nicopress.com/products/category/wire-rope/Entertainment-Performing-Arts?type=Oval

In this video it says aluminum sleeves are NOT acceptable for rigging applications and to use solid copper sleeves with galvanized steel cable.