Ericson 25, Trailering Crutches

Mast crutches are useful pieces of equipment for any trailerable sailboat, especially for one the size of the Ericson 25. Placed at the bow and the stern, the mast crutches serve two functions during trailering: they hinder movement of the mast, and, because they support the mast both forward and aft, they hinder the flexing of the mast at its midpoint atop the cabin. With all of this support, an added benefit is that they reduce the likelihood of damage to the cabin top (and the mast itself) while traveling down the road. Without mast crutches, one must use the bow pulpit as a crutch so to speak. This is, of course, good neither for the pulpit nor for the deck through which the pulpit is bolted.

The bow crutch dimensions are as follows:

Note that the two front legs are welded and formed from a single curved pipe (aluminum?). This causes them to display a strong ‘spring’ effect when squeezed towards each other. They fit between the two deck cleats which are only about 19.5″ apart — and as these legs are 20.5″ apart (18.5″ + 1″ + 1″) on the outside, they’re therefore squeezed tightly against the deck cleats when deployed.

These legs originally each had an outward pointing ‘spike’ welded onto them:
This ‘spike’ lodged itself between the two pillars of the deck cleat, thereby preventing lateral movement after the crutch was squeezed between the two cleats. Over time these spikes all broke off (rough roads, jarring). I intend to drill a hole through the leg and to use a stainless steel bolt with a wing nut to achieve the same purpose.
The front leg is attached to the stem head fitting on the deck with a clevis pin (or a Ball-Lok quick-release pin):
The dimensions of the roller assembly are:

The inside of this assembly should probably be lined with some marine grade bunk carpeting.

Nowadays one would probably use a roller assembly purchased from a boat trailer supplier and adjust these dimensions accordingly. For the sake of completeness, here are the dimensions of the original assembly:
The transom crutch attaches to the removed rudder’s gudgeons:
The small slope on the cradle head compensates for the transom’s slope (click to enlarge):

It may be a good idea to lengthen the pintles by an 1″ or so, allowing one to drill a small hole through the diameter near the bottom to accept a hairpin cotter pin — thereby effectively changing the pintle into a clevis pin (or just use a large clevis pin to make the pintle). This will prevent a badly secured cradle from hopping out over a severe road bump.

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