Isomat NG105 Mast

NG2 Masthead Sheave: NG2-3: Factory standard Acetyl Sheave is 85mm (3 3/8") x 15mm (5/8") wide x 22mm (7/8") ID.
NG2 Masthead Sheave - Aluminum: NG2-3A: Anodized Aluminum Sheave is 85mm (3 3/8") x 15mm (5/8") wide x 22mm (7/8") ID, and is much sturdier than the plastic version.
NG2 Masthead Sheave - Aluminum Ball-Bearing: NG2-3ABB: Anodized Aluminum Ball-Bearing Sheave is 85mm (3 3/8") x 15mm (5/8") wide x 22mm (7/8") ID. Unit features Torlon Balls for high load capacity with minimum friction.
*NG2 Short Masthead Sheave Axle: NG2-6S:* Short SS 'Drop-in' Tubular Masthead Sheave Axle is 22mm (7/8") OD x 46mm (1 3/4") long. Hollow Axle fits in Aft side of NG2 Masthead and supports 2 Main Halyard Sheaves (NG2-3 or *NG2-3A*).
*NG2 Long Masthead Sheave Axle: NG2-6L:* Long SS 'Drop-in' Tubular Masthead Sheave Axle is 22mm (7/8") OD x 81mm (3 1/4") long. Hollow Axle fits in Forward side of NG2 Masthead and supports 4 Jib/Spinnaker Halyard Sheaves (NG2-3 or *NG2-3A*).
*NG2 Masthead Clevis Pin: NG2-6P:* SS Clevis Pin is used in NG2 Masthead for attachment of topping lift, lazy jacks, or other items. This item is not standard on all masts and your Masthead may not have a hole drilled for this Pin, but, if not drilled, hole position is marked by an indent. Masthead can be easily drilled to add this item if required. Clevis Pin is 8mm (5/16") diameter with a 52mm (2 1/16") grip length. CPM8-52

NG3 Extruded Mastheads Some NG-105 Masts have been produced using the heavy-duty NG3 Extruded Masthead. For other parts for this Masthead please contact us with details.
NG3 Masthead Sheave: NG3-3: Factory standard turned Delrin Sheave is 110mm (4 5/16") x 21mm (13/16") wide x 18mm (<3/4") ID.
NG3 Masthead Sheave Axle: NG3-6: SS Sheave Axle Clevis Pin is 18mm (<3/4") x 78mm (3 1/16") long.

NG-105 Mast – Jumper Strut Fittings
*NG2 Jumper Strut Fitting, Single: NG2-25S:* SS Bracket for Single (1) 35mm (1 3/8") OD Jumper or Diamond Strut. Welded Bracket has diamond-shaped base that is 122mm (4 3/4") high x 73mm (2 7/8") wide, 38mm OD strut receiver is 78mm (3") long. 555402

NG-105 Mast – Jib Boxes for Fractional Rigs Several other varieties of Jib Boxes and Forestay Attachments are used on the NG-105 Mast Section, See Isomat Jib Boxes and Forestay/Staysail Tangs.
*NG2 Jib Box Ass'y w/ Toggle - 12mm Pin: NG2-30-12A:* *NG2 Jib Box Ass'y w/ Toggle - 14mm Pin: NG2-30-14A:* *NG2 Jib Box Ass'y w/ Toggle - 16mm Pin: NG2-30-16A:* Cast aluminum Jib Box and Forestay Toggle Assembly is designed to be welded in Mast Section. Unit provides a single sheave for an internal Jib or Staysail halyard up to 5/8" diameter and a secure attachment point for Forestays up to 3/8" (10mm) diameter. Assembly uses an 85mm (3 3/8") Acetyl Sheave (NG2-4-16) on a 16mm Axle, (NG2-6B). Toggle mounts on removable 19mm Clevis Pin which can be used to mount optional Spinnaker halyard Spectacle Assembly (NG2-31S), below. Stainless Steel Toggle with Pin (in various pin sizes) is included. Other Pin sizes (1/2" - 5/8") are available, please specify.
	NG2 Jib Box Sheave: NG2-4-16: Acetyl Sheave is 85mm (3 3/8") OD x 20mm (3/4") wide x 16mm (5/8") ID.
	NG2 Jib Box Sheave Axle: NG2-6B: SS 'Drop-in' Sheave Axle pin is 16mm (5/8") diameter x 29.5mm (1 5/32") long.
	*NG2 Jib Box Forestay Toggle, 12mm Pin: NG2-30-12T:* *NG2 Jib Box Forestay Toggle, 14mm Pin: NG2-30-14T:* *NG2 Jib Box Forestay Toggle, 16mm Pin: NG2-30-16T:* Stainless Steel Toggle for use with NG2 Cast Jib Box. Toggle rides on 19mm Pin in casting, lower Clevis pin (in various sizes) is included. Other Pin sizes (1/2" - 5/8") are available, please specify.
	*NG2 Jib Box Toggle Attachment Pin: NG2-30P:* SS Clevis Pin is used in NG2 Cast Jib Box for attachment of Forestay Toggle. Clevis Pin is 19mm (3/4") diameter with a 52mm (2 1/16") grip length. Single Pin is also used for attachment of optional Spinnaker halyard Spectacle Assembly (NG2-31S), below. CPM19-52
	NG2 Jib Box Spinnaker Spectacles: NG2-31S: Optional SS Spectacle Assembly for NG2 Cast Jib Box allows for two (2) Spinnaker halyards and mounts easily on Jib Box Toggle Pin. Cast Stainless 'eyes' are smoothly faired to minimize chafe on halyards up to 1/2" diameter. Spinnaker halyards exit mast through staggered Exit Blocks mounted several feet above Jib Box Assembly and go straight down through Spectacle 'eyes' and forward.

*NG2 Double Jib Box Ass'y w/ Toggle - 8mm Pin: NG2-32-08A:* *NG2 Double Jib Box Ass'y w/ Toggle - 10mm Pin: NG2-32-10A:* *NG2 Double Jib Box Ass'y w/ Toggle - 12mm Pin: NG2-32-12A:* *NG2 Double Jib Box Ass'y w/ Toggle - 14mm Pin: NG2-32-14A:* NG2 Double Jib Box Ass'y w/ Toggle - 16mm Pin: NG2-32-16A: Extruded aluminum Double Jib Box and Forestay Toggle Assembly is designed to be welded in Mast Section. Unit provides two (2) sheaves for internal Jib or Staysail halyards up to 5/8" diameter and a secure attachment point for Forestays up to 3/8" (10mm) diameter. Assembly fits in 4 7/16" high x 1 13/16" wide slot, and uses 85mm (3 3/8") Acetyl Sheaves (NG2-3B10) on a 10mm Axle. Axle slides in through a hole in the side of the Mast, hole is covered with a SS Cover Plate. Toggle mounts on removable 14mm Clevis Pin (CPM14-46). Stainless Steel Toggle with Pin (in various pin sizes) is included. Other Pin sizes (1/2" - 5/8") are available, please specify. B=202304
	Sheave for NG2 Double Jib Box: NG2-3B10: Acetyl Sheave with precision pressed Delrin bushing is 85mm (3 3/8") x 15mm (5/8") wide x 10mm (3/8") ID.
	Sheave Axle for NG2 Double Jib Box: NG2-32SAP: SS Pin is used in NG2 Double Jib Box as Sheave Axle. Straight Pin is 10mm (3/8") diameter x mm (") long.
	*NG2 Double Jib Box Toggle, 8mm Pin: NG2-32-08T:* *NG2 Double Jib Box Toggle, 10mm Pin: NG2-32-10T:* *NG2 Double Jib Box Toggle, 12mm Pin: NG2-32-12T:* *NG2 Double Jib Box Toggle, 14mm Pin: NG2-32-14T:* *NG2 Double Jib Box Toggle, 16mm Pin: NG2-32-16T:* Stainless Steel Forestay Toggle only, for use with NG2 Double Jib Box. Slotted Toggle rides on 14mm Pin, lower Clevis pin (in various sizes) is included. Other Pin sizes (3/8" - 5/8") are available, please specify. Toggle is 35mm wide with 65mm between pin centers, and will accommodate eyes up to 16mm (5/8") thick. Slot is 7mm wide x 50mm deep.
	*NG2 Double Jib Box Toggle Attachment Pin: NG2-32TP:* SS Clevis Pin is used in NG2 Double Jib Box for attachment of Forestay Toggle. Clevis Pin is 14mm (9/16") diameter with a 52mm (2 1/16") grip length. CPM14-52

NG-105 Mast – Exit Blocks Several varieties of Exit Blocks are used on the NG-105 Mast Section, See Isomat Exit Blocks.

NG-105 Mast – Spreaders The NG-105 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 & Components.

NG-105 Mast – Spreader Bases
*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. For Spreaders and Spreader Parts, See BF-4 Spreaders & Components.
*Spreader Base for BF5 Spreader - Port: BF5-35P:* *Spreader Base for BF5 Spreader - Starboard: BF5-35S:* 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-5 Spreader is attached with (1) 12mm clevis pin that goes through a plastic bushing to allow for some shock loading. New Bases have hole for 21mm (13/16") OD Spreader Bushing, BF5-31. Base measures 5 1/2" high (maximum) x 6 3/8" long, and projects 5 1/4" out from the Mast. For use with NG-70 and larger Mast sections. For Spreaders and Spreader Parts, See BF-5 Spreaders & Components.

NG-105 Mast – Spinnaker Cars Several varieties of Spinnaker Cars are used on the NG-105 Mast Section, See Isomat Spinnaker Cars.
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.
NG2 Reaching Strut Mast Eye: NG2-38: Diamond shaped SS Reaching Strut Mast Eye with welded vertical Eye. Unit is 115mm (4 1/2") high x 73mm (2 7/8") wide, and attaches to the side of the Mast with (4) 1/4" screws or rivets. 10mm Eye has (minimum) 40mm (1 1/2") ID.

NG-105 Mast – Exit Plates Several varieties of Exit Plates are used on the NG-105 Mast Section, See Isomat Exit Plates.

NG-105 Mast – Cleats Several sizes of Cleats are used on the NG-105 Mast Section, See Isomat Cleats.

NG-105 Mast – Mainsail Gates
NG2 Mainsail Gate & Screw Kit: NG2-9K: Cast aluminum Mainsail Gate fits NG-60 through NG-105 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, NG2-9, and SS Thumbscrew, *NGA-10.*
	NG2 Mainsail Gate: NG2-9: Cast aluminum Mainsail Gate fits NG-60 through NG-105 Mast Sections. Gate casting is 2 3/8" (60mm) high x 1 7/16" (36mm) wide, with 1/4" (7mm) deep lip. Part is marked 157007.
	NG2 Mainsail Gate Screw: NGA-10: SS Thumbscrew is 4mm diameter with 5/8" (15mm) long thread and has serrated plastic head.
	NG2 Mainsail Gate Screw - All Stainless: NGA-10SS: All Stainless Thumbscrew is 4mm diameter with 5/8" (15mm) long thread and knurled head.
	Mainsail Gate Rivet Nut: NGA-10RN: 4mm Aluminum Rivet Nut is often used to seat NGA-10 Thumbscrews. Rivet Nut is installed in a 6mm (15/64") hole with a special Rivet Nut Tool. Please note that some Masts have been produced with the Mast tapped directly for the Thumbscrew, and do not use this item.
	Mainsail Gate Rivet Nut Tool: NGA-10RNTool: Special Tool for installing 4mm Aluminum Mainsail Gate Rivet Nut includes two (2) Rivet Nuts. Rivet Nut is installed in a 6mm (15/64") hole, Tool requires use of a 7/8" and a 11/16" wrench (not included).

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. For details, See: Isomat AutoReef System.

NG-105 Mast - Gooseneck Brackets & Hardware
*NG2 Gooseneck Bracket: NG2-11:* Cast aluminum Gooseneck Mast Bracket for use with NB-32, NB-40, and NB-55 new-style Gooseneck Assemblies. Bracket fits NG-51 through NG-105 Mast Sections and is fastened with eight (8) 1/4" (6mm) rivets. Bracket has 22mm (7/8") hole at top and 8mm (5/16") hole on bottom side, for use with any of the NB2-1 Vertical Gooseneck Toggle Pins. For Gooseneck Parts not listed below, See NB-32, NB-40, or NB-55 Boom Section.
NB2 Gooseneck Toggle Ass'y w/ Reef Hooks: NB2-1A: Vertical Gooseneck Toggle Pin Assembly with Tack Shackle and Reef Hooks is used to attach the NB2 Gooseneck to Isomat Gooseneck Mast Bracket (NG2-11). SS Toggle Pin has 2 integral Reef Hooks and is 22mm (7/8") diameter with an 8mm (5/16") threaded stud on the bottom, with washer and SS Locknut. Assembly includes Tack Shackle (*NB2-2) and Horizontal Gooseneck Pin (NB2-3*).
NB2 Gooseneck Toggle Pin w/ Reef Hooks: NB2-1: Vertical Gooseneck Toggle Pin with Reef Hooks includes washer and SS Locknut. As NB2-1A, above, but without Tack Shackle and Horizontal Gooseneck Pin. SS Toggle Pin has 2 integral Reef Hooks and is 22mm (7/8") diameter with an 8mm (5/16") threaded stud on the bottom, and has (2) 10mm (3/8") cross-holes for Tack Shackle and Horizontal Gooseneck Pin.
	NB2 Tack Shackle: NB2-2: SS Tack Shackle fits through hole in top of NG2 Vertical Gooseneck Toggle Pins. Shackle has 8mm (5/16") pin, throat width is 22mm (7/8").
	Replacement Screw Pin for NB2-2 Tack Shackle: NB2-2SP: Replacement Screw Pin only for NB2-2 Tack Shackle. Screw Pin has 8mm thread.
	NB2 Horizontal Gooseneck Pin: NB2-3: Clevis Pin is 10mm (3/8") dia. x 49mm (2") long. Used to attach the NB2 Gooseneck to Isomat Vertical Gooseneck Toggle Pin (*NB2-1*).
NB2 Gooseneck Toggle Ass'y w/ Shackle: NB2-1ARA: Vertical Gooseneck Toggle Pin Assembly is used to attach the NB2 Gooseneck to Isomat Gooseneck Mast Bracket (NG2-11). For use with AutoReef Systems not requiring Reef hooks. SS Toggle Pin is 22mm (7/8") diameter with an 8mm (5/16") threaded stud on the bottom, with washer and SS Locknut. Assembly includes Tack Shackle (NB2-2) and Horizontal Gooseneck Pin (NB2-3).
	NB2 Gooseneck Toggle Pin – AR: NB2-1AR: Vertical Gooseneck Toggle Pin includes washer and SS Locknut. As *NB2-1ARA*, above, but without Tack Shackle and Horizontal Gooseneck Pin. For use with AutoReef Systems not requiring Reef hooks. SS Toggle Pin is 22mm (7/8") diameter with an 8mm (5/16") threaded stud on the bottom, and has (2) 10mm (3/8") cross-holes for Tack Shackle and Horizontal Gooseneck Pin.
NB2 Old-Style Gooseneck Toggle Pin: NB2-1XP: Vertical Gooseneck Toggle Pin Assembly is used to attach the NB2 Gooseneck to Isomat Gooseneck Mast Bracket (NG2-11). Has 10mm (3/8") cross pin at top for using the Old-Style Reef Hook/Tack Assembly (NB2-5X). SS Toggle Pin is 22mm (7/8") diameter with an 8mm (5/16") threaded stud on the bottom, has 10mm (3/8") cross-hole for Horizontal Gooseneck Pin (NB2-3), and includes washer and SS Locknut.
	NB2 Old-Style Reef Hook/Tack Attachment: NB2-5X: Really Old-Style formed combination SS Reef Hook and Tack anchor is passed through the tack grommet in sail and clipped over horizontal cross pin in top of special 22mm gooseneck pin, NG2-1XP. Formed from heavy 10mm (3/8") SS rod, unit measures a maximum of 4" (100mm) high x 3 1/2" (90mm) wide.

*NG3 Gooseneck Bracket for 16mm Pin: NG3-11:* Cast aluminum Gooseneck Mast Bracket for use with FB-810 and larger Booms. Heavy-duty Bracket fits NG-86, FM-740 and larger Mast Sections. Bracket is 6 7/8" (175mm) high x 4" (100mm) wide, and attaches to mast with twelve (12) 1/4" (6mm) rivets. Bracket has holes for 16mm (5/8") pin, for use with any of the FB3-1 Vertical Gooseneck Pins.
	FB3 Gooseneck Pin w/ Tack & Reef Hooks: FB3-1A: Vertical Gooseneck Toggle Pin for use with NG3-11 Gooseneck Bracket and FB3-416 Gooseneck Toggle. SS Toggle Pin has 2 integral Reef Hooks and includes captive Tack Pin, washer and SS Locknut. Unit is 16mm (5/8") diameter x 160mm (6 3/8") long (under head) with 12mm Reef Hooks and a 10mm (3/8") tack Pin.
	FB3 Gooseneck Toggle: FB3-416: Gooseneck Toggle is used with NG3-11 Gooseneck Bracket to attach to FB-810 and larger FB Booms. Cast Aluminum Gooseneck Toggle is 3 1/8" high and accommodates 16mm vertical and 14mm horizontal pins. Anodized Toggle is 3 1/8" (80mm) high x 1 9/16" (39mm) wide x (maximum) 3 3/4" (95mm) long, pin holes are on 2" (50mm) centers.

NG-105 Mast – Winch Pads
NG-105 Side Winch Pad: NG105-20: Formed aluminum Bracket fits either side of NG-105 Mast Section. Winch mounting surface on Bracket is 8" (200mm) square. Clear anodized Bracket is 1/4" (6m) thick and fastens to Mast with twelve (12) 1/4" (6mm) rivets. 69
NG-105 Aft Winch Pad: NG105-21: Formed aluminum Bracket fits aft side of NG-105 Mast Section. Designed to mount under the Boom for use with a Reef line winch. Winch mounting surface on Bracket is 5 7/8" (150mm) square and angles aft approximately 12 degrees to align Winch with Outhaul or Reef lines exiting from Boom. Clear anodized Bracket fastens to Mast with eight (8) 1/4" (6mm) rivets. 63

NG-105 Mast - Vang Brackets & Hardware Brackets are available with Toggles to fit any type of Vang. Isomat Masts were often supplied with an solid Vang as standard equipment, they are also commonly added to boats originally supplied without one. See: Isomat/ Sparcraft Solid Vangs, and Isomat Vang Brackets & Toggles.
NG2 Vang Bracket Ass'y for 14mm Pin: NG2-12VBS: Mast Vang Bracket Assembly has 14mm Pin hole for use with Sparcraft Pneuvang. Standard Assembly includes Mast Bracket NG2-12, Vertical Pin Assembly with shackle, NG2-14AS, and *NG2-18S* Vang Toggle. Bracket is fastened with eight (8) 1/4" (6mm) rivets. Bracket is also compatible with other NG2 Vang Toggles, below.
	NG2 Vang Bracket: NG2-12: Cast aluminum Vang Bracket fits NG-51 through NG-105 Mast Sections. Bracket is 4 3/4" (120mm) high x 3 1/2" (90mm) wide, and is fastened with eight (8) 1/4" (6mm) rivets. Bracket has 22mm (7/8") hole at top and 14mm (9/16") hole on bottom side, for use with the NG2-14A Vertical Vang Toggle Pin Assembly, and any of the NG2 Vang Toggles, See: Isomat Vang Brackets & Toggles.
	NG2 Vang Toggle Pin Ass'y: NG2-14A: Assembly converts NG2 Vang Bracket, NG2-12, for use with any of the NG2 Vang Toggles listed below. Includes Vang Toggle Pin (NG2-14), NG2 Vang Bushing (NG2-13), and SS Cotter Ring.
	NG2 Vang Toggle Pin Ass'y w/ Shackle: NG2-14AS: Assembly is as NG2-14A, above, but with shackle, NB2-2, for tying off a Vang tackle.
	NG2 Vang Toggle Pin: NG2-14: SS Clevis Pin is 14mm (9/16") diameter with a 125mm (5") grip length, and has 8mm (5/16") hole for Cotter Ring or Block attachment. Fits vertically in NG2-12 Vang Bracket.
	NG2 Vang Bushing: NG2-13: SS Bushing is used in upper hole of NG2-12 Vang Bracket to adapt it for use with Vang Toggle Pin (NG2-14). Bushing is 22mm (7/8") OD x 14mm (9/16") ID x 16mm (5/8") long.
NG2 Vang Bracket Ass'y w/ Toggle for 3/8" (10mm) Pin: NG2-17A-10: NG2 Vang Bracket Ass'y w/ Toggle for 1/2" (12mm) Pin: NG2-17A-12: *NG2 Vang Bracket Ass'y w/ Toggle for 5/8" (16mm) Pin: NG2-17A-16:*
Complete NG2 Vang Bracket Assembly with Toggle for Vang is available in various Pin sizes. Assembly consists of Vang Bracket NG2-12, Vang Toggle Pin Assembly NG2-14A, and one of the NG2-17 Vang Toggles. Assembly is fastened to Mast with eight (8) 1/4" (6mm) rivets or screws. Please Note that all Vang Toggles shown here (and others) are available separately, See Isomat Vang Brackets & Toggles.
*NG2 Vang Bracket Ass'y w/ 7/8" Toggle: NG2-19A:* Complete NG2 Vang Bracket Assembly with Toggle for Vang with 22mm (7/8") Pin. Assembly consists of Vang Bracket (*NG2-12), Vang Toggle Pin Assembly (NG2-14A), and NG2-19* Vang Toggle with 22mm (7/8") hole. Assembly is fastened to Mast with eight (8) 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.

*NG3 Vang Bracket for 16mm Pin: NG3-11:* Heavy-duty Cast aluminum Gooseneck/ Vang Bracket fits NG-86, FM-740 and larger Mast Sections. Bracket is 6 7/8" (175mm) high x 4" (100mm) wide, and attaches to mast with twelve (12) 1/4" (6mm) rivets. Bracket has holes for 16mm (5/8") pin, for use with any of the FB3-14 Vertical Pins.
	NG3 Vang Toggle Pin Ass'y w/ Ring: NG3-14R: 16mm Vertical Vang Pin Assembly is used to attach various Vang Toggles to NG3-11 Mast Bracket. SS Gooseneck Pin is 16mm (5/8") diameter x 175mm (6 7/8") long (under head), and threaded on the bottom. Assembly with welded 10mm Ring includes washers and 16mm SS Locknut. See: Isomat Vang Brackets & Toggles.

NG-105 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. The NG-105 Mast Section would normally use NG2 Welded Exit Boxes, See Welded Mast Base Exit Boxes.

NG-105 Mast - Deck Collars, Mast Boots & Hardware
NG-105 Mast Boot: NG105-15B: Heavy molded Black Rubber Boot for use with NG-105 Mast section. Lower side of Boot fits over Deck Collar, stepped upper side is trimmed to fit Mast section. 17,70
NG-105 Mast Boot Clamp: NG105-16M: All Stainless Steel Clamp for use with Mast Boot on NG-105 Mast.
NG-105 Deck Collar Boot Clamp: NG105-16D: All Stainless Steel Clamp is suitable for use with Mast Boots on all NG-105 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. Six (6) NGA-18 Wedges are required for use with the NG-105 Mast and NG86-12 Deck Collar.
*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.

NG-105 Deck Collar: NG86-12: Cast Aluminum Deck Collar for use with NG-86 & NG-105 Mast Sections. Deck Collar has provisions for 14 new-style Mast Base Block Studs 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 NG1 or 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 (6) NGA-18 Mast Wedges. Cast Deck Collar is 16 1/16" (406mm) long x 11 1/8" (282mm) wide, and fastens to deck with (6) 3/8" (10mm) screws. Maximum inside dimensions 11 3/4" x 7 5/8".
NG2 Deck Collar Bail: NG2-20: SS Formed Bail is used for attachment of Boom Vang, and fits in integral slot in aft side of Deck Collar. 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-105 Mast - Mast Steps
NG-105 Mast Step - Keel Mount: NG86-1K: Keel-mounted Mast Step for NG-86 & NG-105 Mast Sections attaches to the keel or keelson with (4) 10mm (3/8") bolts in slots allowing for 20mm (3/4") adjustment. Unit features holes (fore & aft) for 14mm Deck tie-down rods. Cast clear anodized Mast Step is 14 1/8" (360mm) long x 7 5/16" (186mm) wide.
NG-105 Mast Step - Plug for Tenon Deck Plate: NG-105-3P: Mast Step Plug is attached to NG-105 or IM-1630 Mast, reinforcing the tube end, and has dual cut-outs to sit on special Deck-mount Mast Base with Tenons, FM3-3DP, below. Welded Mast Step Plug is 11" (280mm) long x (maximum) 7 1/4" (185mm) wide, and has 1 1/2" (40mm) center hole for wiring. 1630
	Deck-mount Mast Base w/ Tenons: FM3-3DP: Mast Step Deck Plate has projecting Tenons designed to mate with NG-105-3P and other Mast Step Plugs. Cast unit is 14 3/4" (377mm) long x 9 1/2" (240mm) wide, and has trapezoidal Tenons (fore & aft) with 4 3/4" x 3 1/2" (110 x 90mm) center cut-out for wiring. Unit has provisions for (8) 14mm Mast Step Block Pins, NG3-21, (2) 12mm NG2-21 Block Studs (forward), and a SS Tab for attachment of a soft Boom Vang. Mast Base fastens to deck with (10) 8mm (5/16") FH Screws. Note that not all Block Pins may be usable depending on which Mast Plug is used with this unit. Also compatible with Mast Plugs for FM-1060, 1395, 2390; NG-105/IM-1630; F-980E, 1410E, 1980E, and 2600E Mast Sections.
	NG2 Mast Step Block Stud Pin - 12mm: NG2-21: 12mm SS Clevis Pin-shaped Block Stud is used for attachment of shackle or block to lead halyards aft. Fits in integral recessed 12mm hole in a variety of Mast Steps and Deck Collars. Block Stud is installed from underside of Casting, Casting must be removed to install Block Studs. Small head Block Stud is 12mm diameter x 45mm (1 3/4") long (maximum), with a 30mm (1 3/16") grip length and a 6mm (1/4") hole for shackle pin or Block bolt.
	NG3 Mast Step Block Pin - 14mm: NG3-21: 14mm SS Block Pin is used for attachment of shackle or block to lead halyards aft. Fits in integral recessed hole in Mast Steps and Deck Collars with 14mm mounting holes. Block Pin is installed from underside of Mast Step Casting, Mast Step must be removed to install Block Pins. Special Block Pin is 14mm (9/16") diameter x 54mm (2 1/8") long (maximum), with a 35mm (1 3/8") grip length and an 8mm (5/16") hole for shackle pin, Block bolt or Block Pin Swivel Assembly.
	NG3 Mast Step Block Pin Ass'y w/ Toggle - 14mm: NG3-21PTA:
	Special 14mm SS Block Pin Assembly includes standard 14mm Pin, NG3-21, and cast SS Toggle with a 8mm (5/16") Pin for attachment of shackle or block. Removable Toggle is attached with a separate 8mm Pin (included), and has 5/8" (17mm) inside jaw clearance. Unit fits in integral recessed hole in Isomat and Sparcraft Steps and Collars with 14mm mounting holes. Block Pin is installed from underside of Mast Step Casting, Mast Step must be removed to install Block Pins.
	NG3 Block Pin Toggle for 14mm Pin: NG3-21TA: Heavy-duty Block Pin Toggle only, as used in NG3-21PTA, above. Investment cast SS Toggle is 26mm (1") wide with a 5/8" (17mm) inside jaw clearance and includes (2) 8mm Pins for attachment to 14mm Block Pin and Block. Assembly fits on NG3-21 Block Pin. Unit is marked 48093000014.
NG-105 Mast Step – Heavy-Duty: NG105-4: Heavy-Duty Cast Aluminum Mast Step for use with NG-105 Mast Section. Mast Step has provisions for up to 16 Block Stud Pins, NG2-21, or up to 8 special NG3 Mast Base Bails, NG3-20A, or any combination thereof, for attachment of Blocks and shackles. Block Pins and Bail are installed from underside of Mast Step Casting, Mast Step must be removed to install Block Pins or Bails. Cast Mast Step is 14 3/8" (365mm) long x 10 7/8" (276mm) wide, and fastens to deck or keel with (4) 12mm Bolts. 556157,S1630-T
NG3 Mast Step Bail Ass'y: NG3-20A: SS Formed U-bolt type Bail is used for attachment of Boom Vang or/and standard blocks for leading halyards aft. Fits in integral holes in NG105 Heavy-Duty Mast Step. Bail Nuts are installed from underside of Mast Step Casting, Mast Step must be removed to install Bails. Bail is made from 12mm (1/2") rod, and is 3" (78mm) long x 1 9/16" (40mm) between centers. Assembly includes Bail and (2) 12mm jam Nuts. .363
NG2 Mast Step Block Stud Pin - 12mm: NG2-21: 12mm SS Clevis Pin-shaped Block Stud is used for attachment of shackle or block to lead halyards aft. Fits in integral recessed 12mm hole in a variety of Mast Steps and Deck Collars. Block Stud is installed from underside of Casting, Casting must be removed to install Block Studs. Small head Block Stud is 12mm diameter x 45mm (1 3/4") long (maximum), with a 30mm (1 3/16") grip length and a 6mm (1/4") hole for shackle pin or Block bolt.
NG3 Threaded Block Stud w/ Triangular U-bracket: NG3-22T: NG-3 SS Block Stud with triangular U-bracket and nut to fit Isomat Steps and Collars with 14mm mounting holes. Stud is 14mm (9/16") maximum diameter with a 12mm thread. Bracket inside has 3/4" (19mm) clearance and includes a 5/16" (8mm) Pin for attachment of shackle or block. As used on NG105-4 Mast Step on Catalina 470, and others.
NG3 Threaded Block Stud w/ U-bracket: NG3-22U: NG-3 SS Block Stud with U-bracket and nut to fit Isomat Steps and Collars with 14mm mounting holes. Stud is 14mm (9/16") maximum diameter with a 12mm thread. Bracket inside has 3/4" (19mm) clearance and includes a 5/16" (8mm) Pin for attachment of shackle or block. As used on NG105-4 Mast Step on Catalina 470, and others.

NG-105 Internal Waterproofing Plug: NG105-WP: Internal Waterproofing Plug is installed in Keel-stepped Masts to prevent water intrusion below deck. Assembly consists of 2 plastic pieces carefully cut to fit Mast interior with central PVC standpipe to allow passage of electrical wires. Unit slides up from the bottom of the Mast to a point just above Deck level where a hole is drilled in Mast to allow for application of expanding foam between plastic pieces. Second hole is drilled just above upper plastic piece to allow water drainage.
	Internal Waterproofing Foam: NGA-Foam: Expanding foam is used for installation of Internal Waterproofing Plug. Single-use can is sufficient for installation of any Internal Waterproofing Plug.

NG-105 Mast Base Halyard Turning Blocks A variety of Mast Base Turning Blocks are used with the NG-105 Mast Steps and Deck Collars, as well as a variety of threaded Block Studs for the NG-105 Deck Collar, See Isomat Mast Base Turning Blocks.

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Spars, Rigging, and Hardware for Sailboats

NG-105 Mast Components
Masthead Parts Jumper Strut Fittings Jib Boxes & Forestay Attachments Exit Blocks Spreaders Spreader Bases Spinnaker Cars Exit Plates Cleats	Mainsail Gates Gooseneck Brackets Winch Pads Vang Brackets & Hardware Mast Base Halyard Exit Boxes Deck Collars, Mast Boots & Hardware Mast Steps Internal Waterproofing Mast Base Halyard Turning Blocks


NG-105 Mast – Masthead Parts NG2 Mastheads are cast from high-strength Aluminum alloy, and are welded into the mast section. Isomat NG2 Mastheads are easily identified by having 4 sheaves (or provision for 4 sheaves) side by side, on the forward side. For Details, See: NG2 Masthead Assembly. Other Mastheads have been used with this Mast Section, Common parts for them are listed below. For parts not listed, contact us with full details.
NG2 Masthead Cover Plate: NG2-1: Cast aluminum Masthead Cover Plate for NG2 standard Masthead. Masthead Cover Plate also provides level surface for mounting Anchor light and has holes and slots for exiting other electrical wires. Unit is 10 1/4" (260mm) long (maximum) x 7 1/8" (180mm) wide, and is fastened with two (2) 6mm screws, NG2-1S, that thread into tapped holes in Masthead.
NG2 Masthead Spinnaker Crane: NG2-2: Heavy SS Masthead Spinnaker Crane is designed to attach to standard Isomat NG2 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. Stainless Steel Plate is (maximum) 4" long x 5 3/8" wide x 1/4" thick, and projects 1 3/8" forward of the masthead. Easily positioned on the masthead, unit attaches with (4) 5/16" (8mm) bolts and locknuts, mounting requires drilling (4) 5/16" holes in the masthead. Unit comes complete with fasteners.