Isomat NB Boom Specifications

Listed below are the Original Isomat Boom Sections. Original Isomat Booms are easily identifiable by their angularity (they are essentially Octagonal, and hard chined), and an integral internal flat track on the bottom for special Boom Bails. Later Booms Sections used by Isomat had smooth sides and an integral internal flat track on the bottom, See: Sparcraft FB Booms.

For replacement Boom Parts, determine which Boom Section you have by measuring maximum Outside Dimensions of the Boom Section.
Click on individual Boom Sections, below, to see hardware commonly used with those Sections.

Note that some Booms have been produced with the Isomat AutoReef (single line) Reefing System, using specially modified Boom End castings and additional components. For details, See: Isomat AutoReef System.

Note that Booms used with Furling Masts sometimes use upgraded Outhaul Systems with special Track and Ball-bearing Outhaul Cars, See: Booms for Furling Masts.

See also Isomat Masts & Components, and Isomat Spreaders & Components.
And Isovang Solid Vangs & Components.

Isomat Boom Sections
Cross-Section (typical)	Section #	Maximum Outside Dimensions (Height x Width)	Wall Thickness	Weight (lbs./ft)	Moments of Inertia Ixx Iyy (in4) (in4)
	NB-16	2 7/8" x 3 1/2" (72 x 90mm)	.070"	1.08	1.11	1.06
	NB-26	4" x 3 1/2" (100 x 90mm)	.098"	1.76	2.48	2.07

	NB-32	5" x 4 3/8" (128 x 110mm)	.098"	2.16	7.04	3.96
	NB-40	5 7/8" x 4 3/8" (150 x 110mm)	.112"	2.71	11.22	4.97
	NB-55	7" x 5 1/8" (180 x 130mm)	.114"	3.72	20.42	6.97
	NB-70	10 1/4" x 4 1/4" (260 x 109mm)	.138"	5.16	65.09	12.88

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