Thimble Dimensions and Compatible Shackles
Good quality, heavy duty galvanised and stainless steel thimbles can present a challenge when it comes to finding a suitable size shackle.
This is especially true with galvanised thimbles for larger diameter ropes.
Commercial Pattern shackles are a tempting solution because they are usually capacious enough to fit over large thimbles.
However the risk of failure is considerable and the galvanised versions will suffer very quickly from corrosion.
Selecting a rated shackle is highly recommended because they are not only much stronger than commercial pattern shackles, but also have the reassurance of a manufacturer guaranteed break load.
e.g.
Green Pin Shackles Yellow Pin Shackles Jimmy Green Galvanised Pin Bow Shackles Jimmy Green Galvanised Pin D Shackles
All these shackles derive extra strength from three important design factors:
- Increased pin diameter size for size, compared with the crown diameter
- Short pin = narrow jaw width
- Small overall circumference
The second two factors mean that a strong enough shackle will not necessarily fit over/around the next attachment/connection point e.g. a swivel, thimble, another shackle
Consequently, you may need more than one shackle to bridge the gap
The tables below chart the inside dimensions of the galvanised and stainless steel thimbles, together with the overall thickness.
The Jimmy Green Team have physically checked the Green Pin shackles (Yellow Pin and and Jimmy Green Galvanised Pin are the same) on each size of thimble and tabled the smallest size shackle that will both fit over, and sit comfortably on each size of thimble.
Thimble | L | W | D | Shackle |
---|---|---|---|---|
6mm | 32mm | 21mm | 11mm | 5mm |
8mm | 34mm | 24mm | 14mm | 9mm |
10mm | 39mm | 26mm | 16mm | 10mm |
12mm | 47mm | 33mm | 18mm | 11mm |
14mm | 47mm | 33mm | 18mm | 11mm |
16mm | 63mm | 42mm | 23mm | 16mm |
18mm | 70mm | 45mm | 25mm | 19mm |
20mm | 93mm | 70mm | 34mm | 22mm |
24mm | 110mm | 74mm | 35mm | 22mm |
28mm | 120mm | 80mm | 42mm | 25mm |
32mm | 160mm | 115mm | 48mm | 25mm |
Thimble = thimble size by rope diameter
L = approximate internal length
W = internal width at the widest point
D = thickness
Shackle = the smallest size shackle (Green, Yellow or Jimmy Green Galvanised Pin) that will fit over, and sit comfortably on each size thimble
e.g. a 6mm thimble requires a 5mm Shackle with 6mm Pin
Stainless steel thimbles are smaller size for size than galvanised.
Thimble | L | W | D | Shackle |
---|---|---|---|---|
8mm | 34mm | 21mm | 11mm | 5mm |
10mm | 45mm | 27mm | 15mm | 7mm |
12mm | 47mm | 31mm | 18mm | 9mm |
14mm | 55mm | 34mm | 20mm | 11mm |
16mm | 65mm | 40mm | 24mm | 16mm |
18mm | 73mm | 46mm | 26mm | 16mm |
20mm | 77mm | 45mm | 28mm | 16mm |
24mm | 83mm | 52mm | 35mm | 19mm |
28mm | 135mm | 80mm | 40mm | 22mm |
32mm | 170mm | 90mm | 42mm | 25mm |
Thimble = thimble size by rope diameter
L = approximate internal length
W = internal width at the widest point
D = thickness
Shackle = the smallest size shackle (Green, Yellow or Jimmy Green Galvanised Pin) that will fit over, and sit comfortably on each size thimble
e.g. an 8mm thimble requires a 5mm Shackle with 6mm Pin