REVENGE Walk-through Sliding Stairs or Ladder

Repair or modification of Boston Whaler boats, their engines, trailers, and gear
jimh
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REVENGE Walk-through Sliding Stairs or Ladder

Postby jimh » Thu Nov 12, 2020 12:57 pm

Note: I created a thread in the old forum describing this repair in 2012. I reproduce the article here in the new forum. I was looking for this thread and had difficulty finding it because I thought it was already in the new forum. It contains some very useful information and may be helpful (and more easily found) here. I have updated the information slightly and incorporated it all into one article.

REVENGE Walk-through Sliding Stairs or Ladder: Repair broken slide bracket

The sliding stairs in the companionway of the REVENGE Walk-Through boats are a rather nifty piece of engineering by Boston Whaler. In 2012 after 22 years of service, the slide mechanism failed on my 1990 REVENGE 22 W-T.

The stairs are teak and are supported at the top by two plastic brackets that slide on a 1-inch diameter stainless steel tube. One of these plastic brackets failed. Of course, it was the one that is hidden under the cabin top, not the one visible on the starboard side of the stairs. Accessing this slide turned out to be rather complicated. I describe the process below.

The tube is supported by three metal brackets: two are visible at either end of the companionway, and a third is hidden behind a bulkhead on the extreme port end of the tube.

To removed the broken bracket it must be slid off the 1-inch tube. This can be only be done on the extreme far (Port) end of the tube. To accomplish this I had to remove the intermediate tube support on the Port side of the companionway. This fitting also contains a set screw that pins the 1-inch tube in place. The fitting is retained by four machine screws and with elastic stop nuts. Once this fitting is removed the 1-inch tube can be manipulated in a greater range of motion.

The 1-inch tube is also supported on the extreme Port end by another fitting. This fitting is fastened with two self-tapping screws into the headliner and cabin top. The tube passes through this fitting and is not retained by a set screw. You must remove this fitting to allow the slide to be pulled off the tube.

In my REVENGE there is also a thin laminated bulkhead that forms the outboard end of the compartment under the Port helm deck which must be removed to get access to the outboard tubing support. This bulkhead is held in place with five machine screws. Without removing this bulkhead it is impossible to access the outboard tube fitting mounting screws.

Once the disassembly is accomplished as described above the plastic slide can be removed from the tube. Of course, you have to also remove the slide from the ladder. It is fastened to the ladder with four machine screws and barrel nuts.

The slide is made from a dark brown plastic material about 0.25-inch thick. At the top there is a 1.125-inch diameter hole through which the 1-inch tube will pass. Four holes at the bottom provide attachment to the ladder. This part is not available as a replacement part from Boston Whaler. The slide was part of the ladder assembly, and the ladder assembly was purchased as a component assembly from a vendor. That vendor is no longer in business.

Since it took a lot of disassembly of the boat to get to the inside slide and remove it, I had what I thought at the time was a brainstorm idea. I would disassemble the other plastic slide from the other end of the ladder--the one in plain sight and easily accessed--and install that one on the inner end of the ladder. In that way I could reassemble most of the ladder and the boat while I went about fabricating the new replacement slide. I removed the other slide and tried to install it on the inner ladder side. I was quite surprised to find that the four mounting holes in the slide did not line up with the ones in the ladder. Apparently, these slide and ladder holes were drilled in-situ and not made as a precision part with repeatable hole locations. Because of the misalignment of the holes the two slides could not be swapped.

Using the old part as a template, I fabricated a new plastic slide using 0.25-inch thick sheet plastic. I found some suitable plastic in the scrap bin at my workplace (where we fabricate all sorts of assemblies from plastic). The material I used is a milky white plastic and has a bit of flexibility, more so than a sheet of acrylic like Plexi-glass. It seemed almost like a Delrin material. The original plastic material used seemed rather stiff and inflexible, and perhaps more brittle. I suspect that the original material was chosen perhaps for the brown color in order to give a nice match to the teak and to remain somewhat inconspicuous. Since this slide will be hidden from sight, the white plastic was not a concern for its visibility.

To make the new slide I cut a piece of the white plastic sheet to the approximate dimensions. Then I carefully drilled the 1.125-inch diameter hole. If the plastic is going to fracture, it will likely be when drilling this large hole. With hole successfully made, I then trimmed the sheet to the proper size to match the old slide using a band saw. I then used a disk sander to smooth and round the end with the hole for the tube. Finally, I drilled the four mounting holes for the ladder, using the old part clamped to the new part as a drilling guide. Other than the different plastic and different color, I have what I think will be an exact replacement part.

If you have a REVENGE with a sliding ladder in the companionway, take care not to break a plastic slide; it is a lot of work to replace one.

Using the Slide Tube as an Electrical Conduit
Before I disassembled the companionway ladder slide system and saw how it was constructed, I had the notion that perhaps the 1-inch tube that runs across the companionway could be used as an electrical cable conduit. I now see that the 1-inch tube is not likely to be useful as an electrical cable conduit because of the way it is terminated on the Starboard side. The fitting at that end is a post fitting and the tube slides over it. This blocks access to the tube as a conduit.

I have not checked the clearances involved, but it seems like one might be able to change the fitting on the Starboard end to be a socket fitting that would fit around the outside of the 1-inch tube. A hole could be made in the bulkhead, and the tube then would be useful as a wiring conduit. However, based on the problem I had with the plastic slide brackets, it would be impossible to service the slide brackets with wiring coming out of the 1-inch tube on either end. All the wiring would have to be pulled out to permit a ladder slide bracket to be installed around the tube.

As a result I have presently abandoned the idea of using the 1-inch tube as a conduit for electrical cable that need to run across the companion way. According to advice I received from others, the electrical cables in a REVENGE W-T that need to cross over the companionway are installed in and hidden by the folded upholstery padding at the top of the companion way that protects your head when traversing the companionway.

Illustrations

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Fig. 1. The sliding companionway ladder with the brown plastic brackets, as seen in a 1987 REVENGE 20 W-T

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Fi. 2. A sketch of the plastic bracket with dimensions.

Nota bene: I discovered that the location and pattern of the four holes attaching the bracket to the ladder were not consistent on my two slides. When making a replacement it is best to duplicate the existing hole locations to exactly match the ones in the ladder for that side. The holes are 0.25-inch diameter.

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Fig. 3. The old (left) and new (right) brackets. The break occurred where the bracket bears onto the support tube. When I made the replacement bracket I increased the thickness of the bracket around the 1-1/8-inch diameter hole. There is sufficient clearance to permit the thicker bracket to operate without interference.

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Fig. 4. The starboard end of the support tube fits over a post mounted as shown. I believe the post fitting is actually an oarlock fitting that has been inverted.

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Fig. 5. The port end of the support tube passes through this fitting; the tube is fixed in position by the set screw.

I found it necessary to remove the set screw and to remove the four mounting bolts of the port-side tube support in order to give the 1-inch tube enough movement to be able to slip off the hidden bracket and remove the broken slide. Reinstalling this support and fixing the set screw were the last steps of the re-assembly.

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Fig. 6. A third bracket supports the tube at the far port end. This bracket also must be removed to accomplish the replacement of the plastic support bracket attachment to the ladder.

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Fig. 7. The hidden tube support in place under the port dashboard area

Nota bene: To get access to the mounting screws of the hidden support I removed the laminated bulwark on the Port outboard side of the storage compartment. When this is removed, the bulkhead on the forward side of the compartment can be temporarily pushed out of the way to permit access to the mounting screws as it otherwise interferes somewhat.

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The replacement ladder slide bracket installed, and, I hope, never to be seen again or repaired again.