A-Frame Bowsprit - Click for large view
First 235 A-Frame Bowsprit
Ballerina gets the Aspin Going - By Art Kara

Here's a simple A-frame bowsprit made for "Ballerina" from inexpensive materials. It's light, cheap, simple, strong, preserves anchor compartment door function and there's nothing to trip over on the fore deck. A dolphin-striker wire forms about the 30-degree angle with the sprit, as recommended for boom vang to boom. Cinching the tack line to the bow rail keeps the striker tight when the Aspin's not up.

(2) 1" x 1" x 4' square aluminum tubes
(1) 1/4" x 1" x 4' aluminum bar
(1) 1/8 x 1" x 4' aluminum bar
(2) 5/16" x 2" stainless steel bolts and Nylok nuts
(2) 5/16" x 1 1/2" stainless steel bolts and Nylok nuts
(8) 5/16" stainless steel flat washers
(1) 1/4" x 3 1/2" stainless steel bolt and Nylok nut
(4) 1/4" stainless steel flat washers
(1) 1/8" 1 x 19 stainless steel wire, about 48" long
(2) 1/8" stainless steel thimbles
(2) 1/8" swage sleeves
(1) 1/4" pin Harken (#138) stamped "D" shackle (West Marine, $15)
(2) tubular spacers 5/8" long, cut from 3/8" OD x 9/32" ID stainless steel tube
- Ace Marine Epoxy
- Goop Marine Adhesive (Ace Hardware, $50)
- US Spars old-style boom gooseneck pin, left over from an upgrade

The square tubes were used full-length. With a table saw, I ripped some of the aluminum bar stock to 7/8", the inside dimension of the aluminum tubing. I epoxyed short pieces into the ends of the tubes for mounting tangs and spacers. First, I heated and bent the tangs to an angle that would mate w/ the toe rail where I had drilled one 11/32" diameter hole on each side midway between two large, stock holes.

The tangs and spacers form a sandwich inside the tube ends to keep the thru-bolts from crushing the tubes. Bedding them in marine epoxy filled the joints and sealed the tubes. The aft tangs extend 5" into the tubing, 5" out (outer sections were not ripped). The forward inboard spacer extends in 5". The sprit's blunt forward end seemed inelegant at first, but mimics the F-235's plumb bow.

After snug-bolting on the A-frame, I supported it, running the tack line to the bow rail, then measured the exact length for the dolphin-striker wire. My local West Marine provides a workbench, swage press and wire cutters at no charge. After fabricating the dolphin-striker wire, I pressed two tubular spacers into its thimbles in a vice. The 1/4" x 4" bolt goes through one, flanked by washers, at the sprit's forward end. A tack block shackles to it. The other captive tubular spacer keeps the "D" shackle from cocking at the tow eye.

An ATN Spinnaker Sleeve (www.atninc.com) snuffer is invaluable in strong winds and sailing solo.

Ballarina's A-Frame Bowsprit Mod as seen from starboard and directly above
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UPDATE 2016 10 Years & Still Going Strong ~ New Mods

Well, it's 2016 and my A-Frame Bowsprit mod has performed without a problem for about a decade of ocean use; not bad for less than $50 in parts

I've since modified the mod, adding a crossmember to carry a Code Zero on a continuous line furler.

In addition, a separate dolphin striker wire was added to support the crossmember's load. And more recently, I added Ipe wood accents

~ Art

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