Isomat NG51 Mast

NG1 Fractional Masthead Cover Plate: NG1-1FL: Cast aluminum Masthead Cover Plate for NG1 Fractional Rig Masthead, standard on NG-51 Masts with Fractional Rigs. Masthead Cover Plate also serves as Sheave separator, provides level surface for mounting Anchor light, and has slots for exiting other electrical wires. NG1 Fractional Masthead uses a single Sheave Axle (NG1-6) and (2) 60mm Sheaves (NG1-4). Cover Plate is fastened with one (1) 6mm screw going through the front of the mast.
NG-51 Masthead Sheave: NG1-3: Factory standard Acetyl Sheave is 50mm (2") OD x 14mm (9/16") wide x 10mm (3/8") ID.
NG-51 Masthead Sheave - Aluminum: NG1-3A: Anodized Aluminum Sheave is 50mm (2") OD x 14mm (9/16") wide x 10mm (3/8") ID, and is much sturdier than the plastic version.
NG-51 Masthead Sheave: NG1-4: Factory standard Acetyl Sheave is 60mm (2 5/16") OD x 14mm (9/16") wide x 10mm (3/8") ID.
NG-51 Masthead Sheave - Aluminum: NG1-4A: Anodized Aluminum Sheave is 60mm (2 5/16") OD x 14mm (9/16") wide x 10mm (3/8") ID, and is much sturdier than the plastic version.
NG-51 Masthead Spinnaker Roller: NG1-5R: Delrin Roller sheave is 18mm (11/16") OD x 14mm (9/16") wide x 10mm (3/8") ID. For use with Internal spinnaker halyards.
NG-51 Masthead Sheave Axle: NG1-6: SS 'Drop-in' Sheave Axle pin is 10mm (3/8") dia. x 40.8mm (<1 5/8") long. Used for all Sheaves and Rollers in all NG1 Mastheads.

NG-51 Mast – Jib Boxes for Fractional Rigs
*NG1 Jib Box Ass'y w/ Toggle (8mm Pin): NG1-30A:* *NG1 Jib Box Ass'y w/ Toggle (10mm Pin): NG1-31A:* NG1 Jib Box *Ass'y* w/ Toggle (12mm Pin): NG1-32A: Cast aluminum two (2) halyard internal Jib Box Assembly with Forestay Toggle for Fractionally rigged Masts. Accommodates a single Jib halyard below the Toggle and a Spinnaker halyard over the Toggle. Toggle is shielded by contoured nose to minimize chafe on Spinnaker halyard. Assembly uses (2) 60mm (2 5/16") Acetyl Sheaves (NG1-4), on (2) 10mm Axles, (NG1-6S). Sheaves are suitable for use with wire or rope halyards up to 7/16" diameter. Assembly fits in mast cutout 5 5/8" (143mm) high x 1 3/16" (30mm) wide. Internal mounting flange is slightly curved to fit a variety of mast sections. Assembly is designed to fit through the mounting slot and is then fastened from the outside with (1) 6mm machine screw which threads into locknut held in casting (machine screw and locknut included). Stainless Steel Toggle (in various pin sizes) is included. Unit measures (maximum) 6 5/8" long x 1 1/2" wide and projects 2 1/2" (maximum) inside of mast. Suitable for use with a variety of mast sections on boats with forestays up to 1/4" or 7mm diameter. Other Pin sizes (5/16" - 1/2") are available, please specify.
*NG1 Double Jib Box Ass'y w/ Toggle (8mm Pin): NG1-30DA:* *NG1 Double Jib Box Ass'y w/ Toggle (10mm Pin): NG1-31DA:* *NG1 Double Jib Box Ass'y w/ Toggle (12mm Pin): NG1-32DA:* Cast aluminum three (3) halyard internal Jib Box Assembly with Forestay Toggle for Fractionally rigged Masts. Accommodates one Spinnaker halyard over the Toggle, and two (2) wire Jib halyards (5/32" (4mm) maximum) below. Toggle is shielded by contoured nose to minimize chafe on Spinnaker halyard. Assembly uses (1) 60mm (2 5/16") Acetyl Sheave for Spinnaker halyard (*NG1-4), and (2) 60mm (2 5/16") Stainless Steel Sheaves for wire Jib halyards (NG1-4NS), on (2) 10mm Axles, (NG1-6S*). Spinnaker sheave is suitable for use with rope halyards up to 7/16" diameter, Jib sheaves are suitable for use with wire halyards up to 5/32" diameter. Assembly fits in mast cutout 5 5/8" (143mm) high x 1 3/16" (30mm) wide. Internal mounting flange is slightly curved to fit a variety of mast sections. Assembly is designed to fit through the mounting slot and is then fastened from the outside with (1) 6mm machine screw which threads into locknut held in casting (machine screw and locknut included). Stainless Steel Toggle (in various pin sizes) is included. Unit measures (maximum) 6 5/8" long x 1 1/2" wide and projects 2 1/2" (maximum) inside of mast. Suitable for use with a variety of mast sections on boats with forestays up to 1/4" or 7mm diameter. Other Pin sizes (5/16" - 1/2") are available, please specify.
	NG1 Jib Box Sheave: NG1-4: Factory standard Acetyl Sheave is 60mm (2 5/16") OD x 14mm (9/16") wide x 10mm (3/8") ID. Used in all NG1 cast Jib Box Assemblies.
	NG1 Jib Box Sheave - Aluminum: NG1-4A: Anodized Aluminum Sheave is 60mm (2 5/16") OD x 14mm (9/16") wide x 10mm (3/8") ID, and is much sturdier than the plastic version. Suitable for use in all NG1 cast Jib Box Assemblies.
	NG1 Jib Box Sheave Axle: NG1-6S: SS ’Drop-in’ Sheave Axle pin is 10mm (3/8") dia. x 22mm (7/8") long. Used for all Sheaves in all NG1 Cast Jib Boxes.
	NG1 Double Jib Box Narrow Sheave: NG1-4NS: Special Narrow Stainless Steel Sheave is 60mm (2 5/16") OD x 6mm (1/4") wide x 10mm (3/8") ID. Used for Jib sheaves in NG1 Cast Double Jib Box Assembly. Sheave is suitable for use with wire halyards up to 5/32" diameter.
	NG1 Double Jib Box Sheave Washer: NG1-4NSW: Special Teflon Sheave Washer is 60mm (2 5/16") OD x 10mm (3/8") ID. Used on each side of SS Narrow Jib sheaves in NG1 Cast Double Jib Box Assembly.
	NG1 Double Jib Box Sheave Separator: NG1-30DS: Stainless Steel Sheave Separator for use in NG1 Cast Double Jib Box Assembly. SS Plate locks into integral notches in casting between the 2 Jib (lower) sheaves and has a 10mm (3/8") hole for the sheave axle.

NG-51 Mast – Exit Blocks Several varieties of Exit Blocks are used on the NG-51 Mast Section, See Isomat Exit Blocks.

NG-51 Mast – Spreaders The NG-51 Mast Section is commonly used with Several different sizes of Spreaders. Standard Spreader Bases are listed below, for Spreaders, Spreader Parts, and other Spreader Bases, See Isomat Spreaders and Components.

NG-51 Mast – Spreader Bases
*Spreader Base for BF3 Spreader - Port: BF3-36P:* *Spreader Base for BF3 Spreader - Starboard: BF3-36S:* Unique spreader base design incorporates (2) sockets for use with stemballs on lower and intermediate shrouds. Cast aluminum bases are welded to the mast and accommodate a variety of spreader angles depending on how the inboard spreader end is cut. BF-3 Spreader is attached with (1) 8mm clevis pin which goes through a plastic bushing to allow for some shock loading. New Bases have hole for 12mm (7/16") OD Spreader Bushing, BF3-31. Base measures 4 1/2" high x (maximum) 4 1/4" long, and projects 3 3/4" out from the Mast. For use with NG-31 through NG-70 Mast Sections. Please specify Mast Section and port or starboard when ordering. For Spreaders and Spreader Parts, See BF-3 Spreaders and Components.
*Bolt-on Spreader Base for BF3 Spreader - Port: BF3-37P:* *Bolt-on Spreader Base for BF3 Spreader - Starboard: BF3-37S:* Identical to BF3-36, above, but attaches to mast with (4) 6mm (1/4") rivets, and (1) 10mm (3/8") bolt going through the Mast. Not as strong as when welded, but especially suited for replacement in the field. Please specify Mast Section and port or starboard when ordering. For Spreaders and Spreader Parts, See BF-3 Spreaders and Components.
*Spreader Base for BF4 Spreader - Port: BF4-35P:* *Spreader Base for BF4 Spreader - Starboard: BF4-35S:* Unique spreader base design incorporates (2) sockets for use with stemballs on lower and intermediate shrouds. Cast aluminum bases are welded to the mast and accommodate a variety of spreader angles depending on how the inboard spreader end is cut. BF-4 Spreader is attached with (1) clevis pin that goes through a bushing to allow for some shock loading. Bases have hole for 21mm (13/16") OD Spreader Bushing. Base measures 5 1/8" high (maximum) x 4 7/8" long, and projects 5" out from the Mast. For use with NG-46 and larger Mast sections. Please specify Mast Section and port or starboard when ordering. For Spreaders and Spreader Parts, See Isomat Spreaders and Components.

NG-51 Mast – Spinnaker Cars Several varieties of Spinnaker Cars are used on the NG-51 Mast Section, See Isomat Spinnaker Cars.
NG1 Spinnaker Pole Mast Eye: NG1-37: Fixed Eye for attachment of whisker or spinnaker pole on the front of the mast. Used where vertical adjustment of inboard pole end is not required. Diamond shaped SS pad is curved to fit the front of the Mast and has welded horizontal Ring. Unit is 65mm (2 3/16") high x 76mm (3") wide, and attaches to Mast with (4) 1/4" screws or rivets. 8mm Ring has 50mm (2") ID.
NG1 Reaching Strut Mast Eye: NG1-38: Diamond shaped SS Reaching Strut Mast Eye with welded horizontal Ring. Unit is 67mm (2 1/4") high x 85mm (3 1/4") wide, and attaches to the side of the Mast with (4) 1/4" screws or rivets. 8mm Ring has 31mm (1 1/4") ID.

NG-51 Mast – Exit Plates Several varieties of Exit Plates are used on the NG-51 Mast Section, See Isomat Exit Plates.

NG-51 Mast – Cleats Several sizes of Cleats are used on the NG-51 Mast Section, See Isomat Cleats.

NG-51 Mast – Mainsail Gates
NG1 Mainsail Gate & Screw Kit: NG1-9K: Cast aluminum Mainsail Gate fits NG-28 through NG-51 Mast Sections. Gate has horizontal slot for Thumbscrew (NGA-10); Gate is ‘opened’ by loosening Thumbscrew and sliding gate away from Mainsail track. Kit includes Gate casting, NG1-9, and SS Thumbscrew, *NGA-10.*
	NG1 Mainsail Gate: NG1-9: Cast aluminum Mainsail Gate fits NG-28 through NG-51 Mast Sections. Gate casting is 2 3/8" (60mm) high x 1 7/16" (36mm) wide, with 1/8" (4mm) deep lip. Part is labeled #157006.
	NG1 Mainsail Gate Screw: NGA-10: SS Thumbscrew is 4mm diameter with 5/8" (15mm) long thread and has serrated plastic head.
	NG1 Mainsail Gate Screw - All Stainless: NGA-10SS: All Stainless Thumbscrew is 4mm diameter with 5/8" (15mm) long thread and knurled head.

AutoReef Fairlead
*AutoReef Fairlead: NGA-65:* SS AutoReef Fairlead is mounted on either side of mast above gooseneck bracket. Acts as fairlead for reef line and stop for sail when reefed with AutoReef (single line) reefing system. Flattened SS ring is welded to diamond shaped SS plate. Ring is 32mm (1 1/4") OD x 16mm (5/8") ID, plate is 65mm (5/8") high x 40mm (1 5/8") wide and is fastened with four (4) 1/4" (6mm) rivets.

NG-51 Mast - Gooseneck Brackets and Hardware While normally supplied with the NG1 Gooseneck Brackets listed below, in more demanding applications the NG-51 Masts use the NG2 Gooseneck Brackets, See NG2 Gooseneck Brackets, as listed under the NG-60 Mast Section.
NG1 Gooseneck Bracket *Ass'y*: NG1-11AC: Cast aluminum Gooseneck Bracket Assembly fits NG-28 through NG-51 Mast Sections. Assembly comes with everything needed to attach directly to New-Style NB-16 or NB-26 Gooseneck Casting. Includes Bracket (NG1-11), Vertical Toggle Pin (NB1-1), Tack Shackle (NB1-2), Horizontal Gooseneck Cylinder (NB1-3), and Gooseneck Toggle (*NB1-4). Bracket is 3 7/8" (98mm) high x 2 3/4" (70mm) wide, and is fastened with four (4) 1/4" (6mm) rivets. For Gooseneck Parts not listed below, See NB-16* or NB-26 Boom Section.
	NG1 Gooseneck/Vang Bracket: NG1-11: Cast aluminum Gooseneck/Vang Bracket fits NG-28 through NG-51 Mast Sections. Bracket is 3 7/8" (98mm) high x 2 3/4" (70mm) wide, and is fastened with four (4) 1/4" (6mm) rivets. Bracket has holes for 12mm (7/16") Vertical Toggle Pin (NB1-1).
	NG1/NB1 Gooseneck/Vang Vertical Toggle Pin: NB1-1: SS Clevis pin is 12mm (7/16") diameter with a 85mm (3 3/8") grip length, and has 8mm (5/16") hole for Cotter Ring or Block attachment. Fits vertically in NG1-11 Gooseneck/Vang Bracket.
	NB1 Tack Shackle: NB1-2: SS Tack Shackle fits through hole in top of vertical gooseneck clevis pin.
	NB1 Horizontal Gooseneck Cylinder: NB1-3: Plastic Cylinder slides through the Gooseneck Casting and the Gooseneck Toggle. Vertical Gooseneck Pin then slides through Mast Bracket, Gooseneck Toggle, and Horizontal Gooseneck Cylinder, in that order. Black plastic cylinder is 1" diameter x 1 1/2" long with hole for 12mm (7/16") pin.
	NB1 Gooseneck Toggle: NB1-4: Plastic Toggle fits in between the ears in the Gooseneck Casting. Horizontal Gooseneck Cylinder then slides through the Gooseneck Casting and the Gooseneck Toggle. All 3 pieces are held together by the Vertical Gooseneck clevis Pin.
NG1 Old-Style Gooseneck Bracket: NG1-11X: Cast aluminum Gooseneck Bracket fits NG-28 through NG-51 Mast Sections. Old-Style NG1 Gooseneck Mast Bracket is cast with horizontal ring for use with Old-Style NB-16 and NB-26 Boom Goosenecks using Plastic Ball Halves and SS Spring Clips (NB1-5 & NB1-6). Bracket is 2 15/16" (75mm) high x 2 3/4" (70mm) wide, and is fastened with four (4) 3/16" (5mm) rivets. Cast horizontal ring is 1 3/4" (45mm) OD x 1" (26mm) ID. This part is no longer available and is shown here for identification only. For Gooseneck Parts used in conjunction with the *NG1-11X* Old-Style Gooseneck Mast Bracket, and for replacement options, See NB-16, or NB-26 Boom – Old-Style Gooseneck Assemblies and Parts.

NG-51 Mast – Winch Pads
NG-51 Side Winch Pad - Clear Anodized: NG51-20: Formed aluminum Bracket fits either side of NG-51 Mast Section. Winch mounting surface on Bracket is 5" (127mm) high x 4 1/2" (115mm) wide. Anodized Bracket is 3/16" (5mm) thick and fastens to Mast with eight (8) 1/4" (6mm) rivets. 66,46
NG-51 Aft Winch Pad - Clear Anodized: NG51-21: Formed aluminum Bracket fits aft side of NG-51 Mast Section. Designed to mount under the Boom for use with a Reef line winch. Winch mounting surface on Bracket is 4 3/4" (120mm) high x 4 3/8" (112mm) wide and angles aft approximately 12 degrees to align Winch with Outhaul or Reef lines exiting from Boom. Anodized Bracket is 3/16" (5mm) thick and fastens to Mast with eight (8) 1/4" (6mm) rivets. 58,46

NG-51 Mast - Vang Brackets and Hardware Brackets are available with Toggles to fit any type of Vang. While normally supplied with the NG1 Vang Brackets listed below, in more demanding applications the NG-51 Masts use the NG2 Vang Bracket, See NG2 Vang Brackets. Isomat Masts were often supplied with an Isovang solid Vang as standard equipment, they are also commonly added to boats originally supplied without one. See: Isomat Isovangs.
NG1 Gooseneck/Vang Bracket: NG1-11: Cast aluminum Gooseneck/Vang Bracket fits NG-28 through NG-51 Mast Sections. Bracket is 3 7/8" (98mm) high x 2 3/4" (70mm) wide, and is fastened with four (4) 1/4" (6mm) rivets. Bracket has holes for 12mm (7/16") Vertical Toggle Pin (NB1-1).
NG1/NB1 Gooseneck/Vang Vertical Toggle Pin: NB1-1: SS Clevis pin is 12mm (7/16") diameter with a 85mm (3 3/8") grip length, and has 8mm (5/16") hole for Cotter Ring or Block attachment. Fits vertically in NG1-11 Gooseneck/Vang Bracket.
NG1 Vang Bracket *Ass'y* w/ Toggle for Rope Vang: NG1-16A: Complete NG1 Vang Bracket Assembly has Toggle with Slot for attachment of Rope (soft) Vang. Assembly consists of Vang Bracket (NG1-11), Vang Toggle Pin (NB1-1), and NG1-16 Vang Toggle with 3/8" x 7/8" (10mm x 22mm) Slot. Assembly is fastened to Mast with four (4) 1/4" (6mm) rivets or screws. Toggle can be replaced with any listed below for later conversion to a Hard (solid) Vang.
	*NG1 SS Vang Toggle w/ Slot for Rope Vang: NG1-16:* SS Welded Vang Toggle with Slot for attachment of Block or Shackle fits *NG1-11* Vang Bracket. SS tube is 1 15/16" (50mm) long and is drilled for 12mm Vertical Pin, *NB1-1.* Welded SS Tab has Slot (3/8" x 7/8") suitable for attachment of most any shackle. Heavy-duty Tab is 7mm (.280") thick and projects 2" (50mm) out from tube.
NG1 Vang Bracket *Ass'y* w/ 3/8" Toggle: NG1-17A: Complete NG1 Vang Bracket Assembly with Toggle for Vang with 3/8" (10mm) Pin. Assembly consists of Vang Bracket (*NG1-11), Vang Toggle Pin (NB1-1), and NG1-17* Vang Toggle with 10mm (3/8") hole. Assembly is fastened to Mast with four (4) 1/4" (6mm) rivets or screws. For use with the NG1 Isovang.
	*NG1 SS Vang Toggle w/ 3/8" hole: NG1-17:* SS Welded Vang Toggle Fits NG1-11 Vang Bracket. SS tube is 1 15/16" (50mm) long and is drilled for 12mm Vertical Pin, *NB1-1.* Welded SS Tab is 5.5mm (7/32") thick and projects 2 1/2" (65mm) out from tube. Tab has 10mm (3/8") hole for attachment of Vang. For use with the NG1 Isovang.
*NG1 Vang Bracket Ass'y w/ 1/2" Toggle: NG1-18-8A:* Complete NG1 Vang Bracket Assembly with Toggle for Vang with 1/2" (12mm) Pin. Assembly consists of Vang Bracket (NG1-11), Vang Toggle Pin (NB1-1), and NG1-18-8 Vang Toggle with 1/2" (12mm) hole. Assembly is fastened to Mast with four (4) 1/4" (6mm) rivets or screws.
	*NG1 SS Vang Toggle w/ 1/2" hole: NG1-18-8:* SS Welded Vang Toggle Fits NG1-11 Vang Bracket. SS tube is 1 15/16" (50mm) long and is drilled for 12mm Vertical Pin, *NB1-1.* Welded SS Tab is 5.5mm (7/32") thick and projects 2 1/2" (65mm) out from tube. Tab has 1/2" (12mm) hole for attachment of Vang.
*NG1 Vang Bracket Ass'y w/ 5/8" Toggle: NG1-18-10A:* Complete NG1 Vang Bracket Assembly with Toggle for Vang with 5/8" (16mm) Pin. Assembly consists of Vang Bracket (*NG1-11), Vang Toggle Pin (NB1-1), and NG1-18-10* Vang Toggle with 5/8" (16mm) hole. Assembly is fastened to Mast with four (4) 1/4" (6mm) rivets or screws.
	*NG1 SS Vang Toggle w/ 5/8" hole: NG1-18-10:* SS Welded Vang Toggle Fits NG1-11 Vang Bracket. SS tube is 1 15/16" (50mm) long and is drilled for 12mm Vertical Pin, *NB1-1.* Welded SS Tab is 5.5mm (7/32") thick and projects 2 1/2" (65mm) out from tube. Tab has 5/8" (16mm) hole for attachment of Vang.
*NG1 Vang Bracket Ass'y w/ 22mm (7/8") Toggle: NG1-19A:* Complete NG1 Vang Bracket Assembly with Toggle for Vang with 22mm (7/8") Pin. Assembly consists of Vang Bracket (NG1-11), Vang Toggle Pin (NB1-1), and NG1-19 Vang Toggle with 22mm (7/8") hole. Assembly is fastened to Mast with four (4) 1/4" (6mm) rivets or screws. For use with the NG2 Isovang. Also recommended for use with Soft (block and tackle) Vangs, as the large hole will accommodate any shackle.
	*NG1 SS Vang Toggle w/ 22mm (7/8") hole: NG1-19:* SS Welded Vang Toggle Fits NG1-11 Vang Bracket. SS tube is 1 15/16" (50mm) long and is drilled for 12mm Vertical Pin, *NB1-1.* Welded SS Tab is 5.5mm (7/32") thick and projects 2 1/2" (65mm) out from tube. Tab has 22mm (7/8") hole for attachment of NG2 Isovang.
*Triple Vang Bail: NGA-69:* SS Welded Vang Bail fits NG-51 and similar Mast Sections. Allows for multiple attachment of vang and other items. SS 10mm rod is welded to heavy plate, plate is 100mm (4") high x 85mm (3 1/2") wide and is attached to mast with (6) 1/4" (6mm) fasteners. 557104

NG-51 Mast - Welded Mast Base Exit Boxes Some Isomat Masts have Welded Exit Boxes at the base of the mast for leading internal halyards out of the Mast at Deck level, rather than higher on the mast using standard Exit Plates. Halyards exit the Mast angled aft, toward the cockpit, eliminating the need for any additional hardware at the base of the Mast. Welded Exit Boxes are especially common on Cruising Yachts. Several varieties of Welded Exit Boxes are used on the NG-51 Mast Section, See Welded Mast Base Exit Boxes.

NG-51 Mast - Deck Collars, Mast Boots and Hardware
NG-51 Mast Boot: NG51-15B: Heavy molded Black Rubber Boot for use with NG-46, 51, and NG-60 Mast sections. Lower side of Boot fits over Deck Collar, stepped upper side is trimmed to fit Mast section. 14,4660
NG-51 White Mast Boot - Special for 7-Bail Deck Collar: NG51-15B-10:
Deluxe Hard molded White PVC Mast Boot to fit NG-51 Mast Section and 7-Bail Deck Collar, NG51-10, below. White PVC Mast Boot is 9 1/4" long x 2 3/4" high. As used on O'Day 34, 35, and some O'Day 30's.
NG-51 White Mast Boot - Special for IP 320: NG51-15BIP: Special Mast Boot to fit NG-51 Mast Section and Island Packet Cast Deck Collar. Hard molded White PVC Mast Boot is 3 1/2" high x 10 1/4" long. As used on Island Packet 320.
NG-51 Mast Boot Clamp: NG51-16M: All Stainless Steel Clamp for use with Mast Boot on NG-51 Mast.
NG-51 Deck Collar Boot Clamp: NG51-16D: All Stainless Steel Clamp is suitable for use with Mast Boots on all NG-51 Deck Collars.

*Mast Collar Wedge – Small Rubber: NGA-18:* Heavy Extruded Rubber Wedge for use with Isomat and other Masts. Small stepped Rubber Wedge is used to support the mast as it passes through the Deck Collar. Wedge is 2 3/4" (70mm) long x 1 1/8" (28mm) wide, and is 15/16" (24mm) thick at the top tapering to 3/8" (10mm) thick at the bottom.
*Mast Collar Wedge – Large Rubber: NGA-19:* Heavy Extruded Rubber Wedge for use with Isomat and other Masts. Large stepped Rubber Wedge is used to support the mast as it passes through the Deck Collar. Wedge is 2 3/4" (70mm) long x 1 1/8" (28mm) wide, and is 1 3/16" (30mm) thick at the top tapering to 11/16" (18mm) thick at the bottom.
*Mast Collar Wedge – Large Wood: NGA-19W:* Wedge for use with Isomat and other Masts. Large stepped Wood Wedge is used to support the mast as it passes through the Deck Collar. African mahogany Wedge is 2 3/4" (70mm) long x 1 1/8" (28mm) wide, and is 1 5/16" (33mm) thick at the top tapering to 3/4" (20mm) thick at the bottom.
*Special One-piece Mast Collar Wedge: NG51-13SW:* Special One-piece Molded Polyurethane Wedge for use with NG-51 Mast and Simple Deck Collar, NG51-13, below. One-piece molded Wedge fits like a glove to give maximum support to the mast as it passes through the Deck Collar. Wedge is (maximum) 9 7/8" (250mm) long x 6 7/8" (175mm) wide x 3 1/4" (30mm) high. As used on Island Packet, and others. 6005500201R

NG-51 Deck Collar – 7 Bail Type: NG51-10: NG-51 Deck Collar – 7 Bail Type w/ Mast Pin Hole: NG51-10PH: Cast Aluminum Deck Collar for use with NG-51 Mast Section. Deck Collar has provisions for 7 bails ((1) NG2-20, aft, and (6) NG1-20, on the sides), for attachment of a soft Boom Vang and up to 6 standard blocks. Cast Deck Collar is 11 1/2" (294mm) long x 8 5/8" (220mm) wide, and fastens to deck with (4) 1/4" (6mm) screws. Maximum inside dimensions 8 9/16" x 5 13/16". The Mast Pin Hole version has a hole drilled on the Mast centerline for use with a 1/2" Pin or Bolt to act as a Deck Tie down. Bcir 25.25. 015,46
NG1 Deck Collar Bail: NG1-20: SS Formed Bail is used for attachment of blocks and lines. Fits in integral slots in sides of NG70 and smaller Deck Collars. Bails are installed from underside of Deck Collar Casting, Deck Collar must be removed to install Bails. Bail is made from 8mm (5/16") rod, and is 2 1/16" (53mm) long x (maximum) 1" (25mm) high.
NG2 Deck Collar Bail: NG2-20: SS Formed Bail is used for attachment of Boom Vang. Fits in integral slot in aft side of Deck Collars. Bail is installed from underside of Deck Collar Casting, Deck Collar must be removed to install Bail. Bail is made from 10mm (3/8") rod, and is 2 3/4" (70mm) long x (maximum) 1 15/16" (50mm) high.
NG-51 Deck Collar – New Style: NG51-12: Cast Aluminum Deck Collar for use with NG-51 Mast Section. Deck Collar has provisions for 12 new-style Mast Base Turning Blocks and a SS Bail, NG2-20, for attachment of a soft Boom Vang. Nut slots on underside of casting and 12mm holes allow for attachment of NG2 threaded Block Studs, and/or Mast Base Turning Blocks, NGA-40 or NGA-41, without unfastening Deck Collar. Includes four (4) provisions for deck tie-down turnbuckles, and slots for (4) NGA-18 and (2) NGA-19 Mast Wedges. Cast Deck Collar is 12" (305mm) long x 9 5/16" (237mm) wide, and fastens to deck with (4) 3/8" (10mm) screws. Maximum inside dimensions 8 7/16" x 5 13/16". Bcir 27.5. 019,4660
NG-51 Simple Deck Collar � Special - Island Packet: NG51-13: Simple Aluminum Deck Collar for use with NG-51 Mast Section provides a clean, uncluttered look without any attachment provisions. Used with Special One-piece Mast Collar Wedge, NG51-13SW, above. Cast Deck Collar is 11" (280mm) long x 9" (228mm) wide x (maximum) 1 3/4" high, and is undrilled to accept all mounting variations. Maximum ID is 8 3/4" x 5 7/8". As used on Island Packet 31, and others. I365E 003 Bcir 26 5/8" .
NG-51 Simple Deck Collar � Special - Island Packet: NG51-14: Simple Aluminum Deck Collar for use with NG-51 Mast Section provides a clean, uncluttered look without any attachment provisions. Used with Special One-piece Mast Collar Wedge, NG51-14SW, above. Cast Deck Collar is 10 3/4" (273mm) long x 8 3/4" (222mm) wide x (maximum) 1 5/8" high, and is undrilled to accept all mounting variations. Maximum ID is 8 1/2" x 5 5/8". As used on Island Packet 32, and others. 560002 Bcir 25 1/16" .

NG-51 Mast - Mast Steps
NG-51 Mast Step – Small: NG51-1S: Small Cast Aluminum Mast Step for use with NG-51 Mast Section. Cast Mast Step is 9 1/4" (236mm) long x 5 3/4" (146mm) wide, and fastens to deck or keel with (4) 1/4" (6mm) FH Screws. 150 nb
NG-51 Mast Step – 5 Bail Type: NG51-2: Cast Aluminum Mast Step for use with NG-51 Mast Section. Mast Step has provisions for 5 bails (NG2-20), for attachment of a soft Boom Vang and up to 4 standard blocks. Cast Mast Step is 9 1/2" (240mm) long x 7 1/2" (190mm) wide, and fastens to deck or keel with (4) 5/16" (8mm) FH Screws on 7 7/8" (200mm) (fore & aft) x 5 7/8" (150mm) (athwartships) centers. 132
NG-51 Mast Step – New Style: NG51-5: Cast Aluminum Mast Step for use with NG-51 Mast Section. Mast Step has provisions for 8 new-style Mast Base Turning Blocks and a SS Bail, NG2-20, for attachment of a soft Boom Vang. Nut slots on underside of casting and 12mm holes allow for attachment of Mast Base Turning Blocks, *NGA-40* or NGA-41, without unfastening Mast Step. Cast Mast Step is 9 3/4" (250mm) long x (maximum) 7 7/8" (200mm) wide, and fastens to deck or keel with (4) 1/4" (6mm) FH Screws on 7 3/4" (195mm) (fore & aft) x 4 1/4" (110mm) (athwartships) centers. 179,46
NG2 Mast Step Bail: NG2-20: SS Formed Bail is used for attachment of Boom Vang or/and standard blocks for leading halyards aft. Fits in integral slots in NG-51 and larger Mast Steps. Bail is installed from underside of Mast Step Casting, Mast Step must be removed to install Bail(s). Bail is made from 10mm (3/8") rod, and is 2 3/4" (70mm) long x (maximum) 1 15/16" (50mm) high.

NG-51 Mast Components
Masthead Parts Jib Boxes Exit Blocks Spreaders Spreader Bases Spinnaker Cars Exit Plates Cleats	Mainsail Gate Gooseneck Brackets Winch Pads Vang Brackets and Hardware Mast Base Halyard Exit Boxes Deck Collars, Mast Boots and Hardware Mast Steps Mast Base Halyard Turning Blocks


NG-51 Mast – Masthead Parts NG-51 Masts commonly use one of Two varieties of NG1 Mastheads - one for Masthead Rigs and one for Fractional Rigs. Some NG-51 Masts use the larger NG2 Masthead, See NG2 Masthead for details. NG1 Masthead Rig Masthead is a single casting welded into the Mast Section and is easily identified by having only 2 Sheaves (or provisions for only 2 sheaves) side by side, on the forward side. Masthead allows for 2 rollers (for Spinnaker halyards) above forward sheaves for a total of up to 6 halyards. Masthead includes provisions for Headstay, Backstay, and (2) upper shrouds using Stemball fittings. Sheave Axles are the same in all NG1 Mastheads, but fit in various Axle slots using combinations of up to 3 different size Sheaves and Rollers (listed below) depending upon application. For Details, See: NG1 Masthead Assembly. NG1 Fractional Rig Masthead is a single casting welded into the Mast Section which includes provisions for Backstay and (2) upper shrouds using Stemball fittings. NG1 Fractional Rig Masthead uses a single Sheave Axle (NG1-6) and (2) 60mm Sheaves (NG1-4). For Details, See: NG1 Fractional Masthead Assembly.
NG1 Masthead Cover Plate: NG1-1: Cast aluminum Masthead Cover Plate for NG1 Masthead, standard on NG-51 Masts with Masthead Rigs. NG1 (Masthead Rig) Mastheads are easily identified by having only 2 sheaves (or provision for only 2 sheaves) on the forward side. Masthead Cover Plate also serves as Sheave separator, provides level surface for mounting Anchor light, and has slots for exiting other electrical wires. Unit is 10" (255mm) long (maximum) x 2 3/4" (70mm) wide, and is fastened with two (2) 4mm screws, NG1-1S.
NG1 Masthead Spinnaker Crane: NG1-2: Heavy SS Masthead Spinnaker Crane is designed to attach to standard Isomat NG1 Masthead Rig Masthead. Crane allows for off-center attachment of one or two standard swivel blocks for external spinnaker halyards, See Spinnaker Halyard Blocks. This method of running spinnaker halyards has less friction and eliminates the chafe on halyards that is inherent in the standard internal halyard design – it is the only choice for long-distance racing or cruising. Halyards can be led internally; running from the swivel block to an entrance 5-8 feet down from the masthead, but this method does add a potential chafe spot. Attaches with (2) 1/4" bolts and locknuts, and (2) 4mm (5/32") screws that go into the threaded holes for the masthead Cover Plate screws. SS Plate is (maximum) 3 7/8" long x 4 3/8" wide x 3/16" thick, and projects 2" forward of the masthead. Mounting requires drilling (2) 1/4" holes in the masthead. Unit comes complete with fasteners. Masthead crane will not fit Fractional Mastheads.

Spars, Rigging, and Hardware for Sailboats