Started:

Completed:

Type:15'-2" x 6'-0" Cabin Sail Boat

Location:

Built By: Devlin Designing Boat Builders; Conversion - Chelcie Liu

Link to the Nancy's China Page in the Design Catalog

This web page shows the conversion Chelcie Liu did on a Nancy's China rig. It was originally a stepped wooden mast and was converted to tabernacle/carbon fiber rig.

I have always liked Sam Devlin’s stitch and glue designs. So, when I was able to acquire one of his “Nancy’s China” designs (15'2" LOA) for a “good price”, I did so. This particular boat was sprit rigged and had an 18-foot, 30-pound, un-stayed, solid wood mast that was stepped through the deck (Mast 1.0). I found this mast awkward to step and unstep, so decided to experiment with a carbon fiber tube with wood at both ends, but still stepped through the deck (Mast 2.0)

After making this mast, I found that the new 15-pound mast was indeed much easier to step and unstep. However, it was still awkward, and there was that hole in the deck. The next try (Mast 3.0) was stepped on the deck with a tabernacle made from standard 6061-T6 aluminum, 4-inch square, tubing with 1/4-inch wall thickness.

The aluminum tabernacle was connected to the cabin face by five 5/16-inch stainless steel machine screws that were through bolted. The top three pass through a piece of 3" x 3/4" mahogany in addition to the 1/2-inch plywood of the front of the cabin.

Other than filling the original hole in the deck, no modification to the boat was needed because the deck, original mast partner, and the cabin were so strongly constructed.

After cutting off the base of Mast 2.0 and some excess tubing, I made a new base from a piece of Douglas fir 4 x 4. Two Teflon spacers (1/8-inch) were put on one side and two ultra-high molecular weight (UHMW) plastic spacers (1/8-inch) on the other side of the mast base to see which, if either, of these two low friction materials had an advantage. (So far they seem to perform equally well.) UHMW plastic spacers were also placed on the fore and aft sides of the mast base.

The aft edge of the spacers and the forward edge of the aluminum tabernacle were beveled so that the mast base could slide into the tabernacle but would have a tight friction fit. The mast is hinged on a 1/2-inch stainless steel bolt. The aluminum was sanded and painted with System 3® water reducible linear polyurethane that seems to both adhere well to the aluminum and to withstand abrasion.

Even with the weight of the tabernacle and its hardware (all bolts, nuts, etc.) added in, the Mast 3.0 system is lighter and has a lower center of mass than Mast 1.0. So, not only is it easier to raise and lower Mast 3.0, the boat is more stable with this system. Also, without the mast in the cabin, there is more flexibility in how the limited space can be used.

I decided to keep the original main, but change from a sprit to a gaff rig. Both the gaff and a new boom were made from pieces of carbon fiber masts that I obtained at a windsurfers’ swap meet. This was also my source of the carbon fiber mast for my sailing canoe (another story) and is a good source for strong, lightweight tubing for spars. Wood was used to construct the ends of the gaff and boom.

The wood ends for mast, boom and gaff were carefully turned on an old metal working lathe for a snug fit and attached to the carbon fiber with System 3® epoxy. The gooseneck was made from Delrin®.

Another benefit of deck stepping the mast is that the connection point for the gooseneck is now in a place where there is solid wood surrounded by the carbon fiber tube. I was thus able to replace the experimental plastic tab structure that was attached to the mast with hose clamps, with an aluminum tab that is attached to the mast with a 3/8-inch stainless bolt that passes through the mast into threads on the aluminum tab. Both the head of the bolt and the aluminum tab are seated in pieces of teak that are curved to match the curve of the mast.

The unstayed mast and mast step are strong enough that with 350 - 400 pounds of human ballast on the windward seat, and the lee deck edge submerged, the mast and step made no “funny sounds” and showed no sign of weakness.

One of the first changes made to the sail rig was roller furling to make jib handling from the cockpit possible. With Mast 3.0, roller furling is not only very convenient, it adds an extra safety factor as it helps to stay the mast, even when the jib is “down”. The tightly bolted bar at the base of the tabernacle is probably enough to keep the mast up, but I like this extra margin of safety. The jib sheets are now led through Harken cam-matic cleats with X-treme angle fairleads®. I have not had a chance to test these.

To further simplify sail handling, both the throat and peak halyards are led to the cockpit through cam cleats. Now it is much easier to make small adjustments and to quickly raise or lower the main compared to when the halyards were tied off to cleats on the front of the cabin top.

A new mainsheet traveler is my next sail control project. I’m looking forward to next summer so that I can do more testing of the sail controls, and finally spend more time sailing than working on the boat.

It is always nice when working on something new to have knowledgeable advice. Thus, while working on these modifications in Half Moon Bay, CA, I appreciated Kelly Pike taking an interest in what I was doing and his helpful suggestions.

If you have any questions about my experiences with this project, sources of materials, etc., please email me.

See you on the water. -- Chelcie Liu