DN Specifications

H. Rigging

  1. DN Class Information
  2.  » 
  3. DN Ice Yacht Specifications
  4.  » DN Rigging Specifications


Note: Dimensions are given in inches in the English System (except as noted) and in millimeters (MM) in the metric system.

H. Rigging
1. Framing stays are prohibited. Any cable not shown in the plans is prohibited.

2. All stays shall be steel cable and shall be 0.118’’ (3 mm) or greater in diameter.

3. Halyard shall be either steel cable with a minimum diameter of 3/32” (2.4 mm) or rope of optional material with a minimum diameter of 3/32” (2.4 mm.)

4. Bobstay shall be installed and fitted to the bow tang forward and anchored at its after end on the stern block or immediately in front of the runner plank.

5. Tubes and other means of rigid adjustment of stay lengths are permissible.

6. Devices which adjust stay lengths while yacht is underway are prohibited.

7. Means for rigid adjustment of mast step location are permissible.

8. Means for adjustment of mast step location while yacht is underway are prohibited.

9. Mast step shall be rigidly mounted on the deck of the fuselage.10. Mast step shall permit free orientation of mast.

10. Mast step shall permit free orientation of mast.

  English   Metric  
  Max Min Max Min
11. Horizontal distance from mast step pivoting point (center of ball) to pivot axis of steering runner: 41 35 1041 890
12. Horizontal distance from pivot axis of steering runner to pivot axis of steering post: 50 44 1270 1118

13. Distance from lower mast hound bolt (pivot bolt located in front of mast) to base of mast:

  • a. All stays shall connect to a common component (which may consist of one or more sub-components) which attaches to the mast hound at a single point.
139-1/2 127-1/2 3543 3239

14. Six sheet blocks shall be installed.

15. Four sheet blocks shall be installed aft of the rear limit of the cockpit floor: two on the boom and two on the deck. None of these blocks may incorporate a one-way feature. The blocks on the fuselage must be fastened in a manner such that anything penetrating the deck may only be performing the function of fastening, and no other function.

16. One sheet block shall be located forward on the boom within 1’ (304 mm) of the mast. This block may incorporate a one-way feature.

17. One sheet block shall be installed on the tiller post. This block may incorporate a one-way feature.

18. The sheet must be attached to the boom and pass through all blocks as shown in plans.

19. Blocks must be individual and have fixed positions on fuselage and boom.

20. Sheet may run inside the boom between the forward block and the 2nd block.

  English   Metric  
  Min Max Min Max
21. The distance from the center of the runner plank to the base/foot of the side stay on the end of the plank must be: 43.07 1094

22. The components of the mast hound may affect the free orientation of the mast by either forcing mast rotation or limiting mast rotation.


Effective May 31, 2020

H. Rigging
01/01/78: Boom pulleys may not be attached inside the boom by slotting the bottom of a boom and inserting the pulley into the slot and then picking up the sheave with a bolt or rod.

01/01/82: A track may be mounted on the boom for sliders to which the pulleys may be attached.

09/23/82: Mounting Pulleys on deck or boom by any means is acceptable as long as the rope and sheave are outside the boom or deck. No recessed block will be allowed in which part of the sheave or rope is below the back deck. (see also 11/1/84 interpretation)

10/17/83: It is not allowed to use a shock absorber (spring) between side stay and the fitting on the end of the runner plank.

11/1/84: It is not permissible for any part of the sheet block, or any hardware integral with the mounting of the sheet block, to be below the projected top surface of the deck, with the exception of the screws or bolts used to fasten the hardware to the deck.

11/10/73 & 11/14/88: Cable may not be used in place of mast hound. Hound may be made from strap or plate material. No leaders or bridles allowed.