These blocks have an ingenious load-sensitive mechanism that triggers the ratchet only when the sheet load increases. The transistion from ball race sheave to the tough holding power of the ratchet is incredibly smooth, providing the ultimate in hands free operation. Cheeks are made of glass filled nylon with stainless steel straps. Sheaves are of a carbon composite with Delrin ball bearings and stainless steel axles.

Patented extruded hole design provides up to 14:1 holding power. On/off switch on both sides can be operated under load. Swivel-head posts. Applications: dinghy mainsheets, sportboat mainsheets with swivel base, spinnaker sheets on dinghies (especially modern asymmetric classes), sportboats and small keelboats. Max line diameter is 3/8".

The swivel head post can be locked at 0 or 90 degrees using the head post locking kit (RF62100S). All of the Series 60 Ratchets with posts will fit into the RF2450 Stand-up Base and the RF6170 Snap Shackle Head Adapter and the RF6171 Trunnion Snap Shackle Head Adapter. The RF1055 eyestrap and RF324 Stand-up spring work together to stand up the posted blocks for a more permanent installation.

The Series 60 Ratchets used to be Frederiksen blocks, but have been rebranded as Ronstan.

Patented extruded hole design provides up to 14:1 holding power. On/off switch on both sides can be operated under load. Swivel-head posts. Applications: dinghy mainsheets, sportboat mainsheets with swivel base, spinnaker sheets on dinghies (especially modern asymmetric classes), sportboats and small keelboats. Max line diameter is 1/2".

The swivel head post can be locked at 0 or 90 degrees using an Allen wrench on the included set screw The RF72700_ and RF72900_ blocks have ratchets only on the bottom sheaves of the bottom blocks, and use 50mm sheaves for the smaller blocks. Line diameter is 3/8" to 1/2". Use the 3:1 coarse, 6:1 fine RF72700_ mainsheet system on end boom sheeting systems with mainsails up to 38 square meters (409 square feet) and on mid-boom sheeting systems up to 23 square meters (248 square feet). Use the 4:1 coarse, 8:1 fine RF72900_ mainsheet system on end boom sheeting systems with mainsails up to 42 square meters (452 square feet) and on mid-boom sheeting systems up to 27 square meters (290 square feet).

The Series 75 Ratchets used to be Frederiksen blocks, but have been rebranded as Ronstan.

For high speed, low friction performance. Exceptional holding power enables spinnaker sheet trimmer to gybe without using winches in controlled conditions. Spinnaker sheets on boats up to 33'. Max line diameter of 9/16".

The Series 100 Ratchet used to be Frederiksen, but have been rebranded as Ronstan.

Take the shackle off the post of your block and replace it with this adapter to make a snap-shackle block. Accepts a 3/8" post and 3/16" pin. Works with all Ronstan Series 40 blocks with posts (ie. not loop heads), Series 50 singles (only, the post on the Series 50 doubles and triples is too thick), all posted Series 60 Ratchets, and the light load Series 75 Ratchet single (RF72100L).

For non-ratcheting blocks in this range, please visit Synchro & Synchro Control Blocks.

Lewmar's Racing range is designed for high strength to weight ratio and smooth rolling for rapid line handling. Blocks with posts have a three-position head allowing the shackle to be locked in-line, perpendicular to the sheave or to spin freely. The 60mm Racing Ratchet Blocks have dual Delrin ball races, and alloy cheeks and alloy sheaves, with recessed ratchet lever switch.

Lewmar's Racing range is designed for high strength to weight ratio and smooth rolling for rapid line handling. Blocks with posts have a three-position head allowing the shackle to be locked in-line, perpendicular to the sheave or to spin freely. The 80mm Racing Ratchet Blocks have dual Delrin ball races, alloy cheeks with alloy ratchet sheaves, and recessed ratchet lever switch.

When you need to keep size and weight to a minimum, but you need a ratchet, the 40mm Carbo Ratchets from Harken are made to order! Sheaves are machined, hardkote anodized aluminum with eight facets on the ratcheted sheaves to hold line securely. A recessed switch changes modes between ratchet and free flowing, except on the models with cam arms, which always in ratchet mode. Sheave diameter is 1 9/16" (40mm).

Hand hold loaded lines and control release using 57mm Carbo Ratchets. Machined aluminum sheaves have eight facets to hold line securely with 10:1 advantage when the block is ratcheting. Recessed switch allows on/off control for the ratcheting mechanism. For the ultimate system mount a switchable ratchet in the cockpit and a Ratchamatic on the boom to allow double holding power in heavy air and to ensure the mainsheet runs out freely in light air. Use for main, jib and spinnaker sheets, traveler controls and foreguys. Sheave diameter is 2 1/4" (57mm).

The H2137 Cheek comes with RH fasteners and mounting pad. The load ratings for the blocks with Cams are based on the cam strengths.

57mm sheave, 3/8" maximum line size. The Carbo Ratchamatic is a load-sensing ratchet block that rolls freely in both directions under low loads, and automatically engages the ratchet as loads increase. When changing gears, the over-center shifting between ratchet and light air modes is crisp and seamless. Unloaded main and jib sheets run out like greased lightning during mark roundings. Asymmetrical spinnakers that require the tough holding power of a ratchet, also free instantly to give you perfect, effortless jibes. And how about this terrific feature? With the simple twist of an allen wrench you can adjust ratchet engagement to a higher or lower load to suit your own muscle power or sailing style. Great for main and jib sheets; also asymmetric spinnakers.

Hand hold loaded lines and control release using 75mm Carbo Ratchets. Machined aluminum sheaves have eight facets to hold line securely with 15:1 advantage when the block is ratcheting. Recessed switch allows on/off control for the ratcheting mechanism. For the ultimate system mount a switchable ratchet in the cockpit and a Ratchamatic on the boom to allow double holding power in heavy air and to ensure the mainsheet runs out freely in light air. Use for main, jib and spinnaker sheets, traveler controls and foreguys. Sheave diameter is 2 15/16" (75mm).

The H2672 Cheek comes with RH fasteners and mounting pad.

The Carbo Ratchamatic is a load-sensing ratchet block that rolls freely in both directions under low loads, and automatically engages the ratchet as loads increase. Shifting between ratchet and light air modes is seamless. Unloaded main and jib sheets run out freely during mark roundings and asymmetrical spinnakers free instantly during jibes.

Sheave is Hardkote-anodized with eight faces for secure line holding. Ratchet engagement may be adjusted to a higher or lower load according to strength and sailing style. The Ratchamatic ckeek block mounts on either port or starboard.

For the ultimate system, mount a Ratchamatic on the boom above a cockpit-mounted switchable ratchet to allow the mainsheet to run freely in light air, and ensure double holding power in heavy air.

Little Hexaratchets grip loaded sheets, yet allow line to be eased with complete control and provide fast trim and release under high or low loads. They provide 10:1 holding power with a 180° wrap and 50 lb (23 kg).

They feature Hardkote-anodized, Teflon impregnated eight-sided sheaves machined from solid aluminum for strength and corrosion resistance, free-rolling Delrin ball bearings, UV-stabilized sheave and sideplates and high-strength stainless steel straps.

Use the H043 Single, Counterclockwise with the H019 Single, Clockwise on spinnaker and jib sheets where the ratchets must rotate in opposite directions and on/off switches must face up. Note that the counterclockwise slider switch is white, while blocks with clockwise ratcheting have black sliders.

The H020, H041, and H398 are being phased out and are only available by special order for matching existing systems. For new systems, please consider the 57mm Carbo Ratchets and Ratchamatics.

Hexaratchet II+2 blocks grip loaded sheets, yet allow line to be eased with complete control and provide fast trim and release under high or low loads. They provide 15:1 holding power with a 180° wrap and 50 lb (23 kg).

They feature Hardkote-anodized, Teflon impregnated eight-sided sheaves machined from solid aluminum for strength and corrosion resistance, free-rolling Delrin ball bearings, UV-stabilized sheave and sideplates and high-strength stainless steel straps.

Use the H044 Single, Counterclockwise with the H009 Single, Clockwise on spinnaker and jib sheets where the ratchets must rotate in opposite directions and on/off switches must face up. Note that the counterclockwise knob switch is white, while blocks with clockwise ratcheting have black knobs.

The H045 and H091 are being phased out and are only available by special order for matching existing systems. For new systems, please consider the 75mm Carbo Ratchets and Ratchamatics.

Use Harken Hexa-Cat Bases to build powerful mainsheet systems and tackles. In a Hexa-Cat system the upper and lower blocks swivel independently so the cam block pivots to face the trimmer even when the main is sheeted hard. Hardkote-anodized aluminum 3.00 inch (76mm) ratchet sheaves on the H170 and Hardkote-anodized aluminum 2-1/4 inch (57mm) ratchet sheaves on the H193, both with free-rolling carbon-black filled ball bearings for a minimum of friction. 

Part No.

Description

Sheave Dia.

Length

Weight

Max Line

Shackle Dia.

SWL

Break Strength

in

mm

in

mm

oz

g

in

mm

in

mm

lbs

kg

lbs

kg

H170

Hexa-Cat/150 Cam-Matic

3

76

7-1/4

184

16.5

468

7/16

12

1/4

6

-

-

3000

1361

H193

Little Hexa-Cat/150 Cam-Matic

2-1/4

57

5-3/4

146

12

340

3/8

10

1/4

6

-

-

2500

1134

Low-Profile Triple ratchet systems are used on catamarans that carry booms close to the deck and for mainsheet and vang systems on offshore boats.

Rachets grip loaded sheets, yet allow line to be eased with complete control. They feature Hardkote-anodized, Teflon-impregnated eight sided sheaves machined from solid aluminum for strength and corrosion resistance, and free-rolling Delrin ball bearings. The sheave and sideplates are UV-stabilized for maximum protection and high-strength stainless steel straps reinforce the blocks.

The H152 is being phased out but is available by special order to replace parts in existing systems. Please consider a similar Carbo block for new systems.

LD - Light-Duty

Use Harken Ratcheting Fiddle blocks for mainhseets and vangs, and for other three- or four-part tackles. They come in a variety of configurations. First there are Fiddles with Little Hexaratchets and with Cam-Matic H150 aluminum cam cleats on adjustable arms.  With a high load-carrying capacity, the large Harken 2.25inch (57mm) sheaves and small 1-1/2 inch (38mm) sheaves in these fiddles have free-rolling  ball bearings for a minimum of friction. Max line size 3/8 inch (10mm).  Harken Fiddle blocks come in a variety of configurations including fiddles with Hexaratchets and H150 Cam-Matic aluminum cam cleats on adjustable arms.

With a high load-carrying capacity, the large Harken 3.00 inch (76mm) sheaves and small 1-3/4 inch (44mm) sheaves in these fiddles have free-rolling ball bearings for a minimum of friction. Max line size 3/8 inch (10mm). Use Harken Midrange Fiddle blocks use a wider large Harken 3.00 inch (76mm) sheaves and small 2.00 inch (51mm) sheaves in these fiddles have free-rolling ball bearings for a minimum of friction. Max line size 9/16 inch (14mm).  All of the Harken ratchet Fiddle blocks have shackles and headposts and feature Harkens --Three-Way Head-- system that allows the swivel to be locked in front or side position or left to swivel freely.

Harken Midrange Hexaratchets' robust construction makes them ideal to handle the high loads found on medium and large offshore boats. They feature free-rolling Delrin ball bearings, UV-stabilized sheave and sideplates and stainless steel sidestrap. Harken's Three-Way Head system allows you to lock the swivel in front or side orientation or allow it to spin freely.