The Taming of The Stairs

For many years, we have struggled with the stair unit. When in place, and locked in position, it functions well and is a safe and convenient means of transit between the cockpit and the cabin. However, when engine access is needed, it must be removed and it becomes a heavy, unstable and unmanageable piece of hardware with no easy means of storage. It is best stowed by laying the unit on the cabin sole where it occupies a large amount of space.

We pondered various solutions for stowage of the stair unit, including hinging the unit at the bridge deck, hoisting it to the overhead and locking it to the overhead. This would prevent access to the outside and would become a hazard to anyone working below the stowed unit. this concept was quickly rejected.

We also considered adding hinges to one side of the unit that would allow it to be opened, like a door, to allow engine access. This would involve providing clearance to allow the unit to rotate. Since only limited space for access would be provided, this idea was also rejected.

We finally got the idea that it would be nice if the unit would stand up on its own and and be stable after it was slid out of it's normal position. This requires a means of support that provides the necessary stability to balance the unit. Many different contraptions were considered before we settled on extensions for the base of the unit.

The assembled extensions are shown in this picture. This photo is taken of the bottom of the stair unit, with the extensions in place. The extensions consist of lengths of one inch, square aluminum tubing with round, adjustable felt pads on each end. The extensions are about ten inched long. They are set in frame work made of mahogany 1X4 stock with supports made from aluminum angle stock. The assembly is attached to the inside of the stair unit with wood screws.

Extension Unit Installed

The next photo shows the stair unit standing, erect, on the cabin sole. For those familiar with the boat and the stairs, this is rare event. For this picture the extension unit was attached with a pair of c-clamps.

Extension unit, standing, temporary mounting

Th extensions provide quite a bit of stability to the stair unit. In fact, a significant heel angle can be accommodated. The next photo shows the tipping-point angle for the stair unit, with the extensions in place.

Unit With Extensions, Tipped

By now, you are wondering where do the extensions go when the the stairs are in normal position.

This photo shows the extension unit, removed from the stairs and placed in the normal position.

Extension Unit In Normal Position

The extensions protrude into the engine compartment, beside the longitudinal bulkheads that support the engine mounts. This photo clearly shows the asymmetry of the opening for the stair unit, The aft ends of the extensions nearly contact the vertical brackets of the engine mounts. This limits the length of the extensions.

The felt pads on the aft ends of the extensions are supported by and slide on supports that we added to the vertical bulkheads. These supports are at the same level as the cabin sole and function as a continuation of the sole. The starboard and port supports are shown in these photos.

Port Support

Starboard Support

A support consists of a 1-1/2 by 1-1/2 square mahogany block that extends from the end of the sole, along the vertical bulkhead, as far as the engine mount bracket. The top surface of the block is at the same level as the lower surface of the plywood sole (3/4 inch below the top surface). The supports are attached to the bulkhead with lag screws. A section of 3/4 inch thick by 1-1/2 wide teak stock is cut to fit and is attached to the top of each support block with a pair of screws that are countersunk to be flush with surface. The provides a smooth, sliding surface for the felt pads that is the same level as the sole.

Since the extension unit has been installed, we find it to be convenient a safe way to manage removal and stowage of the stair unit. The felt feet make sliding of the unit on the sole easy and a pleasure. The advantages for this design are that there are no loose pieces and no tools are required. The unit has added very little weight to the assembly and the cost has been quite low. However, mahogany is not cheap.

Lessons Learned:

1. Don't suffer with things that are difficult to deal with.
2. Keep considering various solutions and select the most effective one. Experiment with it and keep
    it if it works.