Spars, Mast Hinge, Part 2: Analysis II

The mast step after its removal from its reinforced base
As a precursor to the ordering of the mast hinge for Oystercatcher, my Ericson 25, I removed the mast step and inspected the reinforced fiberglass base upon which it sat. This base is also referred to as a mast step, but to avoid confusion, I will refer to it here as the base. The heavy duty hinge that I would order from Dwyer Aluminum Mast Company was rectangular in shape, whereas the reinforced base was oval.
There were three flat-headed wood screws (1/4 inch in diameter) that secured the step to the base. As I would later discover, this part of the deck consisted of plywood reinforced fiberglass, instead of the balsa wood reinforced fiberglass found elsewhere. The wood screws, therefore, made sense.
The mast step was also secured to the base with a long, 1/4 inch machine screw that was through-bolted so to speak, insofar as there was a piece of hardware on the underside that served as a nut. This piece of hardware was a stainless steel loop with a threaded end on it. This loop did double duty as a nut for the 1/4 inch machine screw and as a terminus for the centerboard line.
In the picture below we see the loop, the line, and the centerboard pendent. I should note that this line was not functional at this point. I merely used it to keep the pendent in a vertical position during my refitting of Oystercatcher. There was no danger of the centerboard falling, since the boat, at this point, was sitting atop her trailer.
The 1/4 inch machine screw as it appeared prior to my removal of it.
The 1/2 inch hole in the center of the base was of course for the centerboard line. The other, pear-shaped hole was for the mast wiring and the VHF coaxial cable.
The step came off of the base with little effort on my part. The bedding compound had long ago dried out and become brittle.
Even though Oystercatcher was tented, her deck would still sometimes get a scattering of water on it during heavy downpours. Dew would also cover her deck on foggy mornings. For this reason I covered the base temporarily with Gorilla brand white duct tape.
One of the first things I realized when I surveyed the deck as a whole was that the forward hatch might be an obstruction to my use of the Dwyer brand mast hinge. I ran piece of survey string from the pulpit to the base to get a sense of the angle of the mast when stepping it.
You'll recall from my previous posting that I had gotten the idea to use the Dwyer mast hinge from an E23 owner in Virginia. He never mentioned that he had a problem with his forward hatch, and there was a reason for this . . . there was not a problem. I went back and looked at the photo he had sent me. I did not see a forward hatch in the vicinity of the hinge. I then looked at other photos of other E23s and realized that the deck layout of the E23 is considerably different from the E25.
An Ericson 23 with a the base of a heavy duty Dwyer mast hinge installed
With this in mind, I began to focus on the fabrication of a custom trailering crutch - one that might allow me to increase the initial angle of the mast. I figured that if I could increase the initial angle enough, then I would be able to keep the mast clear of the forward hatch. The factory original trailering crutch (that apparently came with those Ericson 25s that had the tabernacles) was designed to sit on the deck of the boat, near the bow, not much higher than the top of the pulpit.
It was clear from my experiment with the survey string that I needed to get the mast up higher than the pulpit. This led me to consider an extension for the winch post of the trailer. I created a mock-up with a piece of scrap lumber and asked a buddy to stop by and take a look at it. Being a boatyard owner and an adept welder, he said that he could easily add such and extension.
This seemed to be the answer to my problem, that is, until I went and read the official mast-stepping instructions from Ericson and talked to a fellow E25 owner who was well versed in the stepping of his own mast. The instructions (and this owner) spoke of rolling the mast forward and then picking up the mast slightly to enable the spreaders to pass over the roller. In the picture below from the official instructions we see a man picking up the mast to allow the steaming light to pass over the roller. For some reason Ericson did not show him doing the same with the spreaders, but Ericson did stress in the instructions that this was necessary. Ericson was right to do so, for how else would anyone be able to roll the mast forward?
The mast must extend beyond the bow of the boat by some 2/3 of its length before its base reaches the tabernacle. I think you get the picture.
The point is that while my mock-up seemed to be a solution to the problem, it was not. There was simply no way that I, while standing on the bow of the boat, would be able to pick up the mast enough to allow the spreaders to pass over the roller when the roller was five or six feet forward of the pulpit. There was just not enough leverage.
Accepting the facts of the situation, I turned to another attempted solution. This one involved setting up a roller on the pulpit itself. I had read of other persons with other boats doing something similar.
I began by cutting a piece of 2 x 6 material to the proper length. To this I through-bolted galvanized bunk brackets that I had purchased from West Marine. I had also purchased a roller from West Marine. Their prices were no different than the prices I found online. That was surprising. At any rate, I bolted this roller through the two brackets, and in the process I included several washers to ensure that the roller would turn freely in this space.

Much to my dismay, the added height of the board, brackets and roller on the pulpit did not appear as if it would bring the mast up enough to enable me to step it with the Dwyer mast hinge that I planned to order. Therefore, I began to think of a way to add an extender to the structure - and extender that I would install at the boat ramp just before launching the boat.
The initial small extender mock-up did not do enough, so I created a larger mock-up to test the angle.
This one appeared as if it would enable me to step the mast without interference from the forward hatch.
Unfortunately, however, upon closer examination I discovered that even this lengthy extender was not long enough.
This was when I started thinking that maybe it would help matters if I somehow built up the base so that the mast hinge was higher up and thus the forward hatch was less of an issue.
Bear in mind that I had not yet even considered what the angle would need to be for me to step the mast with the forward hatch in place. I was so accustomed in this refitting to seeing the hatch not there that I had not even considered this. When I set the hatch temporarily in place, I was shocked to discover that the angle necessary for stepping the mast was insanely steep.
I knew right then and there that regardless of what I did, I would probably need to remove the hatch temporarily whenever I wished to step and un-step the mast with this Dwyer mast hinge. Fortunately, to do so would involve not screws and screwdrivers, but two simple cotter rings.
Removing the forward hatch and raising the base with a mock-up block, I got the impression that the extender would indeed work.
Motivated by this realization, I proceeded to construct the pulpit roller assembly more fully, adding a more pieces of 2 x 6 material that would help to secure it in place.
My idea was that this 2 x 6 sandwich would firmly grip the pulpit whenever I trailered the boat. It was also my belief that this would help to hold the assembly in place whenever I added the extender for stepping the mast.
I constructed the extender out of plywood. The roller at the top, I figured, would do double duty. Not only would it allow me to roll the mast forward, but also it would help to keep the two plywood cheeks of the extender true. This structure did seem to be quite stable, but the pulpit roller assembly was not as stable as I had hoped. The problem was that this extender was a lever of sorts, and with the mechanical advantage that it offered, it was not difficult to cause the roller assembly to wobble.
The problem was that there was some wiggle room between the 1 inch stainless steel tubing of the pulpit and the 2 x 6 sandwich. To remedy this problem I installed some black strips of Starboard.
The Starboard made for a snug fit.
My creation looked a bit awkward, but I didn't care, I only needed the extender to help me step the mast at a boat ramp.

Satisfied with the bow, I now turned to the stern. Using another 2 x 6, I created a platform that would support a crutch.

I made sure to center this platform on the center of the roller assembly at the bow. The surveyor's string was a big help.
I double checked my centerline by dropping a plumb line. Everything looked good.
Just as I had done on the bow roller assembly, I softened the edges of the 2 x 6 material with a round-over bit on the router and some 40 grit sandpaper on the quarter-sheet sander.
I also used the paddle bit to counter sink the heads of the galvanized bolts.

I did not want a roller on this stern assembly. I wanted the mast to be held snugly in place. Therefore, I mounted these galvanized trailer bunk brackets more closely together than I did the ones at the bow. To these I would later add bunk carpet.

Having completed both the bow roller assembly and the stern bracket assembly, I decided it was time to give the extension a try. The Dwyer mast hinge was already in the mail, and I figured that by putting the mast itself on the extension I would be able to determine just how high I needed to build up the mast base before mounting the mast hinge.
I will say right now that this whole extension idea of mine was the most asinine thing to emanate from my mind during this entire refitting. What made me think that this un-reinforced plywood contraption could support the weight of the bulky and unwieldy mast of the Ericson 25? I'll never know, but I do know that I felt true fear when the Admiral and I and my young son stood on the cabin of the boat and loaded that mast into the extension. We rolled it forward, not the 2/3 of its length that we needed to roll it forward, but instead only about 1/3 of its length. The plywood cheeks of the extension waved to and fro, and it seemed that at any moment the entire thing would snap. I considered ourselves lucky to have done what we did and to have gotten that mast off of the boat with it (and ourselves) still fully intact.
Eventually, with the help of my boatyard-owner friend, a solution to this problem was eventually found. It involved him welding a piece of galvanized steel vertically atop the winch post. To this extension he welded the two galvanized trailer bunk brackets. Into these brackets I reinstalled the roller. I am, though, getting ahead of myself in talking about all this.
The Dwyer mast hinge was in the mail, and one thing was certain: if I did not build up the old mast base (or mast step as it is commonly called), then nothing I did at the bow would ever work. With this in mind, I began to think about how I  might augment the base.
This ends this posting on my analysis of the old and the new concerning my efforts to add the Dwyer mast hinge to Oystercatcher, my Ericson 25.

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