INSTRUCTIONS
One Ton Twing Block, 3405
USA – Tel: (+01) 262-691-3320
Web: www.harken.com
Email: harken@harken.com
Italy – Tel: (+39) 031 3523511
Web: www.harken.it
Email: techservice@harken.it
WARNING! Strictly follow all instructions to avoid an accident, damage to your vessel, personal injury, or death. See www.harken.com/manuals for additional safety information.
Uses
- Twing, tweeker control for code zero sheets
- Can be used as snatch block when combined with soft shackle
- Spinnaker sheet and guy control
Features
Side opening sideplate – Easy to rig and remove from sheet
Spring loaded button release – Quick one-handed rigging
Anti-capsize bar – Keeps sheave aligned on sheet
ULC main bearing – Sheave turns smoothly under extreme loading
Sideload balls – Carry loads especially when block not aligned in light air
Thimble at pivot base – Use 1:1 or 2:1 up-down control
Machined aluminum inner sideplates – High strength, low weight
Soft polyurethane outer sideplate bumpers – Protects block and deck
Terms
Specifications
| Part No. | Description | Sheet max line 0 | Up/down max line 0 | Wei ht | G – Maximum workin load |
Breaking load | |||||
| in | mm | in | mm | oz | g | lb | kg | lb | kg | ||
| 3405 | 1 Ton Twing Block | 0. | 11 | 0. | 9 | 1. | 143 | 2205 | 1000 | 4409 | 2000 |
Rigging Options
1:1 up-down control
Splice or knot to thimble at pivot base.
2:1 up-down control
Use a control line around thimble at pivot base.
Use
Hold the block in one hand and use your index finger to press the release button. Load onto sheet. Close and latch the sideplate. Listen for an audible click.
IMPORTANT! Do not load sheave when sideplate is unlatched. Make sure sideplate is latched before loading.
If sheet is larger than 5/16″ (8 mm) remove the anti-capsize bar to allow a larger sheet to be used.
The anti-capsize bar can also be removed if the up-down control is 1:1 and a spliced eye is used, thus avoiding capsizing.
IMPORTANT! Do not load anti-capsize bar to secure loaded control line or sheet. Use thimble and sheave only to secure to loaded lines.
To make the sideplates easier or harder to rotate, adjust the tension on the adjusting nut.
WARNING! Loosening the adjusting nut too much can result in lock mechanism not engaging. Verify lock mechanism before each use.
WARNING! Loosening the adjusting nut can result in the nut spinning freely, not securing the block in the closed position. If you can spin the nut without tools, it is too loose. Replace using a Nylock Nylok is a registered trademark of Nylok Corporation.
Maintenance
Periodically clean release button mechanism, sheave, and hinge base with mild detergent and water solution.
Note: Spin sheave to distribute soap solution into sideload balls and main bearing evenly. Open and close sideplate. Flush with fresh water. Do not use lubricants in sheave.
Warranty
For additional safety, maintenance, and warranty information see www.harken.com/manuals or the Harken catalog.
Documents / Resources
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HARKEN 3405 1 Ton Twing Block [pdf] Instructions 3405 1 Ton Twing Block, 3405, 1 Ton Twing Block, Twing Block, Block |