Sparcraft IMS-80 Mast

IMS-80 Fractional Masthead Ass'y: F78-FHA: Cast aluminum Masthead Assembly for F-78 and IMS-80 Tapered Masts with Fractional Rig. F-78 Fractional Masthead is 9" long, Crane extends 6" from aft face of mast and includes 6mm (1/4") clevis pin for Backstay. Unit includes (2) 40mm (1 1/2") Sheaves, FM0-3, and 8mm clevis pins for Sheave Axles. Multiple Sheave positions allow for external Main halyard, or internal Main and Masthead Spinnaker halyards. As used on J/80, and others.
	F-78 Fractional Masthead Sheave: FM0-3: Factory standard Delrin Sheave is 40mm (1 1/2") OD x 10mm (3/8") wide x 8mm (5/16") ID.
	F-78 Fractional Masthead Sheave Axle: CPM 8-22: SS Sheave Axle Clevis Pin is 8mm (5/16") OD with a 22mm (7/8") grip length.
	F-78 Fractional Masthead Backstay Pin: CPM 6-28: SS Clevis Pin for Backstay is 6mm (1/4") OD with a 28mm (1 1/8") grip length.

IMS-80 Mast – Tangs A wide variety of Tangs are used on the IMS-80 Mast Section, but most commonly used are Stemball Backing Shell Tangs. See also, other Tangs.

IMS-80 Mast – Jib Boxes & Forestay Attachments Although the IMS-80 Mast commonly uses the FM0 Jib Box, the heavier-duty NG1 Jib Box is used in some applications, as on the Hunter 260. Several other varieties of Jib Boxes and Forestay Attachments are used on the IMS-80 Mast Section, See Isomat Jib Boxes and Forestay/Staysail Tangs.
*WE Double Jib Box Ass'y w/ Stemball Socket: FM0-30A:* Cast aluminum two (2) halyard internal Jib Box Assembly with Stemball Socket for Fractionally rigged Masts. Accommodates two (2) Jib halyards up to 5/16" (8mm) diameter, and features a 20mm Stemball Socket for Forestay attachment. Assembly uses (2) 40mm (1 9/16") Delrin Sheaves, FM0-3, for Jib halyards on an 8mm Axle, FM0-6L. Assembly fits in mast cutout 3" (76mm) high x 1 1/2" (37mm) wide. Assembly is designed to fit through the mounting slot and is then pulled down, a screw or rivet is then installed above the casting to keep it locked in place. Unit measures (maximum) 3 7/8" long x 1 11/16" wide and projects 1 1/4" (maximum) inside of mast. Commonly used with FM-35 thru FM-101 Mast Sections.
	FM0 Jib Box Sheave: FM0-3: Black Delrin Sheave is 40mm (1 9/16") OD x 10mm (3/8") wide x 8mm (5/16") ID. Used for Jib halyard sheaves in FM0-30A Jib Box. SM40R10-8
	FM0 Jib Box Sheave Axle: FM0-6L: SS 'Drop-in' Sheave Axle pin is 8mm (5/16") dia. x 31mm (1 1/4") long. Used for Sheave Axle in FM0-30A Jib Box.

*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. As NG1-30A, above, but with two (2) wire Jib halyard Sheaves, NG1-4NS, (5/32" (4mm) maximum) below the Toggle. Other Pin sizes (5/16" - 1/2") are available, please specify.
	NG1 Forestay Toggle w/ 8mm Pin: NG1-30-8T: NG1 Forestay Toggle w/ 10mm Pin: NG1-30-10T: NG1 Forestay Toggle w/ 12mm Pin: NG1-30-12T: SS Toggle only for use with a variety of NG1 Fractional Forestay Attachments. Formed SS Toggle is (minimum) 14mm wide x 4mm thick and approximately 58mm (2 1/4") between Pin centers. 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.

Forestay Attachment Ass'y - 10mm: FM1-31-10A: Forestay Attachment Assembly with 10mm Rod Nose. Milled backing plate is attached inside the Mast with (2) 1/4" rivets, 10mm nose threads into backing plate and is fastened with (2) 5mm screws. Aluminum Backing plate is 7 1/4" long x 1 3/16" wide (185 x 30mm). Shown with NG1-30 Toggle (purchase separately), below. As used on J/80.
	NG1 Forestay Toggle w/ 8mm Pin: NG1-30-8T: NG1 Forestay Toggle w/ 10mm Pin: NG1-30-10T: NG1 Forestay Toggle w/ 12mm Pin: NG1-30-12T: SS Toggle only for use with a variety of NG1 Fractional Forestay Attachments. Formed SS Toggle is (minimum) 14mm wide x 4mm thick and approximately 58mm (2 1/4") between Pin centers. Other Pin sizes (5/16" - 1/2") are available, please specify.

IMS-80 Mast – Exit Blocks Several varieties of Exit Blocks are used on the IMS-80 Mast Section, See Isomat Exit Blocks.

IMS-80 Mast – Spreaders The IMS-80 Mast Section is commonly (but not always) used with BF-2 Spreaders. Standard Spreader Bars are listed below, for Spreaders, Spreader Parts, and other Spreader Bases, See Sparcraft Spreaders & Components.

IMS-80 Mast – Spreader Bars
Spreader Base Clevis Pin: BF2-30: Attaches BF2 Spreader to standard Cast Aluminum Base. SS Clevis Pin is 8mm diameter x 22mm (7/8") long.
*Rectangular Aluminum Spreader Bar for BF-2 Spreader: BF2-40-0:*
Aluminum Spreader Bar for BF2 Spreader is 11 3/4" long x 12mm thick x 20mm wide (1/2" x 13/16"), and incorporates a 5 degree vertical angle for 0 degree (in-line) Spreaders. When ordering please specify Mast Section. Also available with a variety of sweep-back angles on special order.
*SS Spreader Bar for BF-2 Spreader, 19° aft: BF2-41-19:* Rectangular Stainless Steel Spreader Bar for BF2 Spreaders angled 19 degrees aft is (maximum) 11 3/4" (300mm) long x 20.5mm wide x 12mm thick (1/2" x 13/16"), and incorporates a 5 degree vertical angle. Unit has (4) 8mm holes for attachment Pins. As used on J/80.
*SS Doubler Plate for BF-2 Spreader Bar: BF2-40N:* Formed SS Doubler Plate is formed to fit NG-28 Mast Section and reinforces it for use with any BF2 Rectangular Spreader Bar. Unit features boss to allow a straight cut on the spreader end. Plates (2 required) are attached to the mast with (4) 3/16" rivets, and have 12mm x 25mm (1/2" x 1") Slot for BF2-40 Spreader Bars. Plate is (maximum) 2 7/8" (75mm) long x 2" (50mm) high. For use with FM-35 thru FM-101, NG-28 and similar Mast sections.

Note: Aluminum and SS Spreader Bars for BF2 Spreaders also available in a variety of lengths and angles not listed here, and are sometimes machined for use with a variety of wire and rod Stemballs. When inquiring please specify Mast Section, sweepback angle, and rigging configuration.

IMS-80 Mast – Spinnaker Cars Spinnaker Cars on the IMS-80 Mast Section, normally run of one of several sizes of added T-Track, See Spinnaker Cars for T-Track.
FM1 Spinnaker Pole Mast Eye: FM1-37: 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, Cast SS Pole eye is curved to fit the front of the Mast. Base is 46mm (1 3/4") high x 47mm (1 7/8") wide, and attaches to Mast with (4) 3/16" (5mm) screws or rivets on 32mm vertical x 35mm centers. 8mm Ring has 40mm (1 1/2") ID. Used with FM-35 through FM-101, and other Mast Sections.

IMS-80 Mast – Exit Plates Several varieties of Exit Plates are used on the IMS-80 Mast Section, See Isomat Exit Plates.

IMS-80 Mast – Cleats Several sizes of Cleats are used on the IMS-80 Mast Section, See Isomat Cleats.
Spar Cleat - 5" long: D-10325: * Cast Aluminum Spar Cleat is a low-profile design with a narrow base suitable for use with line up to 1/2" diameter. Black Epoxy coated Cleat is 5" long, and fastens to spar with (2) 7/32" (#12) FH screws on 1 1/2" centers. As used on J/80. *Used in all US production.

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 eight (4) 1/4" (6mm) rivets. As used (2pcs.) on J/80.

IMS-80 Mast – Mainsail Gates & Feeders
FM1 SS Boltrope Feeder: FM1-BRF: SS Boltrope Feeder fits FM-35 through FM-101 Mast Sections. Cast SS Feeder is 3" (78mm) long x (maximum) 1 5/8" (42mm) wide and attaches to mast with (4) 3/16" (5mm) rivets on 28mm x 64mm vertical centers. Unit requires 65mm x 14mm cut-out in the Mast track. Replaces earlier Plastic version and fits in same cut-out. Part is labeled 34203000034. As used on J/80.

FM-80 Mast - Gooseneck Brackets & Hardware The FM-67 Mast Section is normally used with NG1 Gooseneck Brackets, for Booms up to FB125.
NG1 Narrow Gooseneck Bracket: NG1-11N: Cast aluminum Gooseneck/Vang Bracket is used on a variety of smaller FM Mast Sections. It is compatible with all FB and NB Gooseneck Toggles that use a 12mm Pin. Bracket is 3 7/8" (98mm) high x 1 15/16" (49mm) wide, and is fastened with four (4) 1/4" (6mm) rivets. Bracket has 12mm (7/16") holes for use with any of the NB1-1 Vertical Gooseneck Toggle Pins, below. Commonly used with FM-35 thru FM-101 Mast Sections. As used on J/80.
	NB1 Gooseneck Pin Ass'y w/ Reef Hooks: NB1-1RA: Stainless Steel Reef Hook/Tack Assembly incorporates 12mm Vertical Gooseneck Bolt with Tack Shackle and dual Reef Hooks. Reef Hooks are formed from 8mm rod, Assembly is (maximum) 3 5/8" wide x 6" high, and includes 5mm SS Tack Shackle. Bolt is 12mm diameter x 3 5/8" long for use with any of the NG1-11 Gooseneck Brackets and a variety of Gooseneck Toggles for a 12mm Pin. As used on J/80.
	NB1 Gooseneck Connector Kit: NB1-1K: NB1 Gooseneck Connector Kit for applications not requiring Reef Hooks. Kit has everything necessary to connect Gooseneck Casting to Mast Bracket and includes all 4 of the components below, NB1-1, NB1-2, NB1-3 and NB1-4.
	NB1 Vertical Gooseneck 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 Shackle attachment. Fits vertically in any of the NG1-11 Gooseneck/Vang Brackets.
	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.
	NB1 Tack Shackle: NB1-2: SS Tack Shackle fits through hole in top of vertical gooseneck clevis pins. Shackle has 5mm (3/16") pin.

IMS-80 Mast - Vang Brackets & Hardware Vang Brackets used on the IMS-80 Mast Section are listed below, as are commonly used Vang Toggles. For other Vang Toggles used with these Brackets, See NG1 Vang Toggles.
NG1 Vang Bracket w/ Toggle for Rope Vang: NG1-16NA: Complete NG1 Vang Bracket Assembly has Toggle with Slot for attachment of Rope (soft) Vang. Assembly consists of Narrow Vang Bracket (NG1-11N), Vang Toggle Pin (NB1-1), and NG1-16 Vang Toggle with 3/8" x 7/8" (10mm x 22mm) Slot. Bracket is fastened to Mast with four (4) 1/4" (6mm) rivets or screws. Toggle can be replaced for later conversion to a Hard (solid) Vang.
NG1 Vang Bracket w/ Toggle for 14mm Pin: NG1-16NA-14D:
Complete NG1 Vang Bracket Assembly has Toggle with 14mm (9/16") hole for attachment of Vang and 8mm (5/16") hole for attachment of Vang Tackle. Assembly consists of Narrow Vang Bracket (NG1-11N), Vang Toggle Pin (NB1-1), and NG1-18-14D Vang Toggle. Bracket is fastened to Mast with four (4) 1/4" (6mm) rivets or screws. As used with Sparcraft Pneuvang and others.
	NG1 Narrow Gooseneck Bracket: NG1-11N: Cast aluminum Gooseneck/Vang Bracket is used on a variety of smaller FM Mast Sections. It is compatible with all FB and NB Goosenecks that use a 12mm Pin. Bracket is 3 7/8" (98mm) high x 1 15/16" (49mm) wide, and is fastened with four (4) 1/4" (6mm) rivets. Bracket has 12mm (7/16") holes for use with any of the NB1-1 Vertical Gooseneck Toggle Pins, below. Commonly used with FM-35 thru FM-101 Mast Sections.
	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.
	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 SS Vang Toggle w/ 14mm & 8mm holes: NG1-18-14D:*
	SS Welded Vang Toggle Fits NG1-11 Vang Bracket. SS tube is 1 15/16" (50mm) long and is drilled for 12mm Vertical Pin. Welded SS Tab is 5mm (3/16") thick and projects 2 3/8" (60mm) out from tube. Tab has 14mm (9/16") hole for attachment of Vang and 8mm (5/16") hole for attachment of Vang Tackle. As used with Sparcraft Pneuvang and others.

IMS-80 Mast - Deck Collars, Mast Boots & Hardware
IMS-80 Mast Boot: IMS80-15B: Heavy molded Black Rubber Boot for use with IMS-80 Mast Section and all standard Deck Collars. As used on J/80 and others.
IMS-80 Mast Boot Clamp: IMS80-16M: All Stainless Steel Clamp for use with Mast Boots on IMS-80 Mast.
IMS-80 Collar Boot Clamp: IMS80-16C: All Stainless Steel Clamp for use with Mast Boots on all IMS-80 Deck Collars.
IMS-80 Mast Boot Clamp: IMS80-16DB: Molded Black wire tie is sometimes used in place of standard Stainless Mast Boot clamps. Looks great and less expensive, but one time use only! As used on J/80 and others. 9x760
IMS-80 Mast Collar Deck Wedge - J/80: IMS80-MW-J80: One piece molded Mast Collar Wedge for IMS-80 Mast Section and special Deck Collar on J/80. Molded Blue urethane Wedge is (maximum) 6 7/8" (175mm) long x 4 7/8" (124mm) wide x 1 7/8" (48mm) high. As used on J/80.

IMS-80 Mast - Mast Steps
IMS-80 Mast Step – Keel-mount: IMS80-3J: Mast Step for IMS-80 Mast Section fastens to keel or keelson with (4) 5/16" (8mm) bolts in external adjustment slots to allow for precise positioning without unstepping the mast. Cast Aluminum Mast Step is 7 1/8" (180mm) long x 4 3/4" (120mm) wide, and allows for 1" fore and aft adjustment. As used on J/80.
IMS-80 Mast Step - Channel Type: FM135-2C: Channel Type Mast Step for F-78, IMS-80 & FM-135 Mast allows wide range of adjustment. Extruded Aluminum Channel is 210mm (8 1/4") long x (maximum) 100mm (4") wide, ID is 90mm (3 1/2"). Unit attaches to Deck with (6) 6mm FH screws and features five (5) holes allowing for up to 87mm (3 3/8") of fore & aft adjustment. Includes 12mm Crossbolt with Locknut and washers.
	*IMS-80 Channel Mast Step - Crossbolt Ass'y: FM135-2CBA:*
	12mm Stainless Steel Crossbolt Assembly used in FM135-2C Channel Type Mast Step. SS Double threaded Pin is 12mm x 143 long and includes locknuts and washers.

See also Sparcraft Booms, and Sparcraft Spreaders. See also, other Sparcraft Mast Sections.

IMS-80 Mast Components
Mastheads Tangs Jib Boxes & Forestay Attachments Exit Blocks Spreaders Spreader Bars Spinnaker Cars	Exit Plates Cleats Mainsail Gates & Feeders Gooseneck Brackets Winch Pads Vang Brackets & Hardware Mast Steps

Sparcraft IMS-80 Mast Section Sparcraft IMS-80 Mast Section is available in a variety of lengths fully anodized. Painted finishes and other lengths are available on special order. If you require a complete Mast Assembly, you can select from components below and contact us with specifications. If you require components not listed below please contact us with complete details.

IMS-80 Mast – Mastheads IMS-80 Masts are produced with a variety of different Mastheads, including the standard Cast Fractional Masthead listed below. Others have been produced using a variety of Mastheads, both welded and bolt-in, for Masthead and for Fractional Rigs. For Parts not listed here, please contact us with complete dimensions.

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Spars, Rigging, and Hardware for Sailboats