2025 Ronstan Marine Catalogue - Catalog - Page 60
KEELBOAT BLOCKS
Series 75 Core
58
14mm (9/16”)
RF74100
RF74100AW
RF74108
RF618T
RF74202
RF74251
RF74151
ALUMINIUM SHEAVE
RF74110
RF74500
2 x 10mm
(3/8”)
RF74140
RF74108A
14mm
(9/16”)
RF618A
8mm (5/16”) pin suits
single shackle head blocks
RF74108A suits 14mm (9/16”) mast
collar post (not supplied)
4 x 6mm (1/4”)
Universal head can be fixed at 0° or 90° or left free
to swivel, by using a 2.5mm hex key.
Mainsheet, spinnaker sheet, vang, halyard and
backstay applications on boats to 14m (46ft).
Ball bearings: High compression strength acetal.
RF74108 Halyard block has a removable
8mm (5/16”) screw pin for attaching to
mast collar or mainsail headboard.
General applications on larger yachts.
Pins: Grade 2205 stainless steel
(RF74108, RF74108A, RF74202).
RF74108A Mast base block has removable
8mm (5/16”) clevis pin to suit a 14mm (9/16”) wide
mast collar post.
PRODUCT No.
Cheek plates: Aluminium alloy.
Sheave: UV stabilised acetal, or anodised aluminium
(SP models).
DESCRIPTION
Ball Bearing
RF618T
Twist shackle body, suits RF64202 & RF74202, for 90° attachment
RF74100
Single block, universal head
RF74108
Halyard block, screw pin with roller head
RF74108A
Mast base block, clevis pin head
RF74110
Single block, becket, universal head
RF74140
Stand-up block, swivelling
RF74151
Foot block, single
RF74202
Double block, non-swivel shackle head
RF74251
Foot block, double
RF74500
Fiddle block, universal head
Special Purpose - Aluminium Sheave
RF74100AW
Single block, rope/wire sheave, universal head
Shackle, post & hub: Grade 316 stainless steel.
SHEAVE MAX. MAX. PIN
DIAM. ROPE WIRE DIAM. M.W.L.
mm
mm mm mm
kg
Padeye: Grade 15-5PH stainless steel.
SHEAVE MAX. MAX. PIN
DIAM. ROPE WIRE DIAM. M.W.L.
in
in
in
in
lb
B.L. WEIGHT
lb
oz
40
354
234
230
428
468
259
506
530
478
3
3
3
3
3
3
3
3
3+1 3/4
9/16
9/16
9/16
9/16
9/16
9/16
9/16
9/16
9/16
6600
6600
6600*1
6600
6600
6600
6600
6600*2
6600
432
3
9/16
B.L. WEIGHT
kg
g
75
75
75
75
75
75
75
75
75+45
14
14
14
14
14
14
14
14
14
-
8
8
8
8
8
1500
1500
1500*1
1500
1500
1500
1500
1500*2
1500
3000
3000
3000*1
3000
3000
3000
3000
3000*2
3000
75
14
8
8
1500 3000
*1 Full block rated load can only be achieved with uniformly distributed load across full length of clevis pin. i.e. 14mm (9/16”) diameter mast collar post or 14mm (9/16”) wide mast collar plate/tang.
*2 Total block load. Maximum load on top sheave not to exceed 50% of total block load.
-
5/16
5/16
5/16
5/16
5/16
3300
3300
3300*1
3300
3300
3300
3300
3300*2
3300
5/16 5/16 3300 6600
1.4
12.5
8.3
8.1
15.1
16.5
9.2
17.9
18.7
16.9
15.3
