Isomat Sheaves & Rollers

Isomat uses a variety of Acetyl (hard plastic) Sheaves in their Mast and Boom applications. Sheaves have a groove for rope or wire. These Sheaves are sufficiently strong to be used with wire halyards, as they are in Europe. Anodized Aluminum Sheaves are manufactured in the U.S., for high load applications and for their greater longevity. The most common Sheaves are listed below, but, as always, there are many "Specials". All Isomat Sheaves run directly on a SS axle. Delrin Reduction Bushings are available for some Sheaves.
Rollers are sheaves without a groove, and are used in a limited number of small-diameter applications. Sheaves and Rollers are listed by size, and by common application.

Part #	OD	Width	ID	Material
NG1-5R, NB1-11R	18mm (11/16")	15mm (5/8")	10mm (3/8")	Delrin (Roller)
NB1-20R	22mm (7/8")	15mm (9/16")	10mm (3/8")	Delrin (Roller)
NB1-10 17	30mm (1 3/16")	10mm (3/8")	10mm (3/8")	Acetyl
NB1-10A	30mm (1 3/16")	10mm (3/8")	10mm (3/8")	Aluminum
NB2-20R	35mm (1 3/8")	15mm (9/16")	10mm (3/8")	Delrin (Roller)
NG1-3 16	50mm (2")	14.5mm (9/16")	10mm (3/8")	Acetyl
NG1-3A	50mm (2")	14.5mm (9/16")	10mm (3/8")	Aluminum
NG1-4, NB2-10 15	60mm (2 5/16")	14.5mm (9/16")	10mm (3/8")	Acetyl
NG1-4A, NB2-10A	60mm (2 5/16")	14.5mm (9/16")	10mm (3/8")	Aluminum
NG1-4ABB, NB2-10ABB	60mm (2 5/16")	14.5mm (9/16")	10mm (3/8")	Alum. Ball-Bearing
NG1-4NS	60mm (2 5/16")	6mm (1/4")	10mm (3/8")	Stainless Steel

NB2-19R	22mm (7/8")	15mm (9/16")	10mm (3/8")	Delrin (Roller)
NB2-20R	35mm (1 3/8")	15mm (9/16")	10mm (3/8")	Delrin (Roller)
NG2-3B10	85mm (3 3/8")	15mm (5/8")	10mm (3/8")	Acetyl
NG2-3AB10	85mm (3 3/8")	15mm (5/8")	10mm (3/8")	Aluminum
NG2-3	85mm (3 3/8")	15mm (5/8")	21.5mm (7/8")	Acetyl
NG2-3A	85mm (3 3/8")	15mm (5/8")	21.5mm (7/8")	Aluminum
NG2-3ABB	85mm (3 3/8")	15mm (5/8")	21.5mm (7/8")	Alum. Ball-Bearing
NGS2-18 18	85mm (3 3/8")	20mm (3/4")	16mm (5/8")	Acetyl
NGS2-19 19	85mm (3 3/8")	20mm (3/4")	22mm (7/8")	Acetyl

NG3-3	110mm (4 5/16")	21mm (13/16")	18mm (<3/4")	Delrin
NG3-3ABB 19	110mm (4 5/16")	21mm (13/16")	18mm (<3/4")	Alum. Ball-Bearing


Isomat Sheaves & Rollers by Application
Mast Sheaves & Rollers
NG 1 Masthead			Part #
	11/16" OD (18mm)	Forward Roller for Spinnaker Halyard	NG1-5
	2" OD (50mm)	Acetyl Sheave, 10mm ID	NG1-3
	2" OD (50mm)	Aluminum Sheave	NG1-3A
	2 5/16" OD (60mm)	Acetyl Sheave, 10mm ID	NG1-4
	2 5/16" OD (60mm)	Aluminum Sheave	NG1-4A
	2 5/16" OD (60mm)	Aluminum Sheave w/ Delrin Ball-Bearings	NG1-4ABB

NG 2 Masthead
	3 3/8" OD (85mm)	Acetyl Sheave, 21.5mm (7/8") ID (6 pieces maximum)	NG2-3
	3 3/8" OD (85mm)	Aluminum Sheave	NG2-3A
	3 3/8" OD (85mm)	Aluminum Sheave w/ Torlon Ball-Bearings	NG2-3ABB

NG 3 Masthead
	4 5/16" OD (110mm)	Delrin 18mm (<3/4") ID (6 pieces maximum)	NG3-3
	4 5/16" OD (110mm)	Aluminum 18mm (<3/4") ID w/ Torlon Ball-Bearings	NG3-3ABB

NG 1 Cast Fractional Jib Box
	2 5/16" OD (60mm)	Acetyl Sheave, 10mm ID (1 or 2 required)	NG1-4
	2 5/16" OD (60mm)	Aluminum Sheave	NG1-4A
	2 5/16" OD (60mm)	Aluminum Sheave w/ Delrin Ball-Bearings	NG1-4ABB
	2 5/16" OD (60mm)	Stainless Steel Narrow Lower Sheave - 1/4" wide (2 required)	NG1-4NS
NG 2 Cast Fractional Jib Box
	3 3/8" OD (85mm)	Acetyl 5/8" ID / 3/4" wide	NGS2-18

NG 1 Welded Mast Base Sheave Box
	2 5/16" OD (60mm)	Acetyl Sheave	NG1-4
	2 5/16" OD (60mm)	Aluminum Sheave	NG1-4A
	2 5/16" OD (60mm)	Aluminum Sheave w/ Delrin Ball-Bearings	NG1-4ABB
NG 2 Welded Mast Base Sheave Box
	3 3/8" OD (85mm)	Acetyl Sheave 10mm ID	NG2-3B10
	3 3/8" OD (85mm)	Aluminum Sheave 10mm ID	NG2-3AB10

Boom Sheaves & Rollers
NB 16, NB 26 Booms			Part #
	11/16" OD (18mm)	Gooseneck and Outboard Roller (3 forward, 2 aft)	NB1-11
	1 3/16" OD (30mm)	Acetyl Outhaul Sheave (1 required aft)	NB1-10
	1 3/16" OD (30mm)	Aluminum Outhaul Sheave	NB1-10A
	7/8" OD (22mm)	Delrin (Shuttle Block Roller)	NB1-20R

NB 32, NB 40, NB 55 Booms
	2 5/16" OD (60mm)	Acetyl Sheave, 10mm ID (all sheaves, 4 in each end)	NB2-10
	2 5/16" OD (60mm)	Aluminum Sheave	NB2-10A
	2 5/16" OD (60mm)	Aluminum Sheave w/ Delrin Ball-Bearings	NB2-10ABB
	1 3/8" OD (35mm)	Delrin (AutoReef / Shuttle Block Roller) 10mm ID	NB2-20R
	7/8" OD (22mm)	Delrin (AutoReef Roller) 10mm ID	NB2-19R

Isovang Sheaves

NG 1 Isovang 2" OD (50mm) Acetyl (2 per end)	NG1-3
NG 2 Isovang 3 3/8" OD (85mm) Acetyl - 3/4" wide (2 per end)	NGS2-19

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