BrianW
Well-Known Member
There are contrasting techniques of terminating tension wires.
1) threading a solid wire through a wound wire and finishing with a hook in the wire
2) threading a cable through a bobbin and ferrule, secured by two three or four crimps
3) threading a cable through a tapered cylinder, with internal threading for a fork or stud or eye, using two jaws and a washer, against which, the cable strands are spread.
4) threading a cable though a tapered cylinder, spreading cable strands, and fixing them with a molten alloy, often lead
5) swedging a wire cable inside a plain hollow cylinder finished with a stud or eye or fork end.
It seems to me that methods 1) & 2) are lightest and possibly weakest attaining perhaps 90% of wire cable strength.
Methods 4) & 5) are considered strongest but heavy, enabling breakage to occur in the cable first.
Method 3) is occupied by terminals which have been noted to slip well below wire rope breaking strain AND (expensive) types which are advertized at 100% of cable strength.
I have been experimenting with a 10 ton electrical cable swedger. This $30 device was intended for swedging coax cables with a steel ferrule or heavy copper cables with copper terminals using hex dies.
For this purpose it requires two dies with a suitably sized circular hole between the two dies.
Acquiring a load cell & instrument amp to register the force applied to test articles seemed excessive so a jig with a 6 in long 1 X 1/4 in mild steel cantilever which deflects 240 thousandths inch when deflected by a 2000 lb pull (typical of 1X19 1/8 in diameter stainless cables) with a micrometer clock gauge on hand is the chosen approach.
1) threading a solid wire through a wound wire and finishing with a hook in the wire
2) threading a cable through a bobbin and ferrule, secured by two three or four crimps
3) threading a cable through a tapered cylinder, with internal threading for a fork or stud or eye, using two jaws and a washer, against which, the cable strands are spread.
4) threading a cable though a tapered cylinder, spreading cable strands, and fixing them with a molten alloy, often lead
5) swedging a wire cable inside a plain hollow cylinder finished with a stud or eye or fork end.
It seems to me that methods 1) & 2) are lightest and possibly weakest attaining perhaps 90% of wire cable strength.
Methods 4) & 5) are considered strongest but heavy, enabling breakage to occur in the cable first.
Method 3) is occupied by terminals which have been noted to slip well below wire rope breaking strain AND (expensive) types which are advertized at 100% of cable strength.
I have been experimenting with a 10 ton electrical cable swedger. This $30 device was intended for swedging coax cables with a steel ferrule or heavy copper cables with copper terminals using hex dies.
For this purpose it requires two dies with a suitably sized circular hole between the two dies.
Acquiring a load cell & instrument amp to register the force applied to test articles seemed excessive so a jig with a 6 in long 1 X 1/4 in mild steel cantilever which deflects 240 thousandths inch when deflected by a 2000 lb pull (typical of 1X19 1/8 in diameter stainless cables) with a micrometer clock gauge on hand is the chosen approach.
