Sailboat cocoons are evolving from within. In yards all across the country you’re seeing more boats growing white skeletons before they don their winter wraps.

PVC skeletons for off-season storage can be put up quickly, provide a large amount of workspace underneath, and are fairly inexpensive. However, designs and techniques are quite varied. We watched a neighbor build his own, then we read a brief article with a few pictures from a cruiser in Boston. We wanted something quicker and easier than we had, (who doesn’t?). So we’ve taken what we could from everybody else, made our own tweaks on their designs, and came up with the following for a Catalina 30’, along with detailed photos and step by step directions on how to do it the way we did, but the hope is the next person will improve the design and process so this evolution of PVC skeletons can continue.

[The basics of this design were provided by Joe Van Benten of Boston for a Bristol 30, published in the Sept/Oct 2007 issue of Good Old Boat. Joe credits Karl Friedland of the Yahoo Bristol Group for his inspiration.] [cut?]

The most important change we made was adding vertical supports down the center at each frame to accommodate a Northern Michigan snow load. We also used some different construction techniques to let us fabricate the whole thing on site, and have provided a detailed parts list so future builders won’t have to make as many trips to the hardware as we did.

The frames are of 1 ¼ inch schedule 40 PVC with four, 45 degree elbows per frame. Each frame is made of five lengths of tube, two vertical segments, two sloped segments, and a top segment. The lateral and top connectors running fore and aft at the top and sides are 1 ½ in. schedule 40 that connects to 1 ½ in. T’s. These T’s slide over the 1 ¼ in. tube nicely and allow a great deal of adjustment and articulation.

We put a frame at and between each stanchion, 12 in all on our 30’ Catalina. We also put a vertical support from the deck to each frame top segment with another 1 ½ in. T. This put three 1 ½ in T’s on each top segment, one in the center for the vertical support, one at each side for the fore and aft top connectors. We thought three T’s forced the top segment to be wider than we wanted so we cut the ears off the outer two T’s to keep our flat area width to a minimum. 

We started at the gate stanchions, the widest part of the boat, but due to the extra support leg on the stanchions we had to slot the 1 ¼ in. tube to go over them, then used stainless steel band clamps to tighten and hold the tube securely. We gestimated a comfortable height of about 30” off the toe rail and cut the vertical stanchion segments accordingly, then slid two 1 ½ in. Ts over the vertical segments before putting on the elbows, these would be used for the fore and aft lateral connectors. We then made our top segment. Three 1 ½ in T’s, the outer two with one ear cut, determined our length, allowing a little extra for each elbow of course. With the top segment fabricated one person held it about where we thought we wanted it while the other measured to the deck for the vertical support length. We used small pieces of 1 by 2 wood slats for the feet of the vertical supports and vertical segments that went in-between stanchions. They fastened to the PVC with a small corner bracket. With the first vertical support cut and installed we could measure for the sloping segment of the frame pretty accurately. The first frame took a bit of measuring and re-measuring and head scratching, but once it was set satisfactorily we simply built all the subsequent frames to it.

For the next frame we used the 1 ½ in. lateral connectors to hold the vertical segments of the frame in place, since this frame didn’t have stanchion tubes to slide over. Then we cut and installed the next 1 ½ in. top connector and vertical support to hold the new frame’s top segment eye ball level with the first one and again cut the sloping segments to fit. Loosely fitting it together as we went helped a great deal in getting it all positioned correctly. Every frame we built added strength and rigidity to the entire structure. Once we got a rhythm going it went together pretty quickly. 

PVC cuts easily with a good handsaw, and they also make special PVC saws. We found it beneficial to have a cutter on the ground, and we tossed pieces up and down to him. It’s easier to cut tube off a pick-up tailgate than in the cockpit or on deck of the boat. 

We built our first frame at the widest part and used it for reference. As we approached the bow we began a slope downwards so the narrowing frames weren’t tall and skinny, and subsequently flimsy. The bow frame ended up being something of a cobble job to accommodate the slightly off center mast. The cobble job at the stern frame came out much nicer. A 4th 1 ½ inch T on this top segment allowed a connector to neatly go to each rail end of our stern rail access. That worked out very well

We didn’t put any setscrews in until done. The elbows and Ts hold their tube inserts very snug when pressed on firmly. But we learned joints that seem tight can still come undone in time without setscrews. Fortunately PVC is very easy to drill and set a screw into. I think it’s best to use screws with a socket head to speed up the process; there are a lot of joints to set.

48 1 1/4 in. 45 degree elbows

82 1 ½ in T fittings (Make sure they’re not swept sewer T’s, the 1 ¼ in. tube must 

slide thru easily)

17 10 ft. lengths of 1 1/4 in. schedule 40 PVC

15 10 ft. lengths of 1 ½ in. Schedule 40 PVC

30 3 in. lengths of 1 by 2 slat for wooden feet, or something similar

30 cheap corner brackets

4 large stainless steel band clamps for the gate stanchions

lots and lots of ¼ in. #8 set screws, we used a 1/8 bit to pilot them

The large number of elbows and T’s cleared the shelves of two home supply stores, so you may have to plan ahead and order or be prepared to hit several suppliers. I feel sorry for whoever might have tried to fix a sink or shower drain the weekend I was buying every elbow and T in town. You must make sure you get T’s that fit nicely over the 1 ¼ in. tube, not all do. My numbers for the tubing could easily be off a couple either way. We had to buy more during construction and then ended up with extra. I wish I would have started with too many and planned on returning some rather than running out during construction.

We’ve used the frame for 10 years now and have had many people in our yard taking pictures and making notes. I tell them all that having a solid labeling system and keeping pieces together during tear down is what makes putting up so easy. We mark every piece with a frame number, port or starboard, and a code for what piece it is, SS for Sloped Segment, LC for Lateral Connector, etc. 

We tear down by frame and keep every piece of tube numbered for that frame bundled together with duct tape. This makes it much easier to sort out in the spring and helps compact the whole system into as small a space as possible for storage.

Every fall I dig out the photos taken during construction just to help refresh how it all fits and what every label represents. The fall assembly is what really impresses people. We now have it down where two people can put it up in about 3 hours. 

Winters are rough in Northern Lake Michigan. The frame has withstood many winter storms, with blizzard winds and crushing snow totals. Every spring, when all the sailboats in our yard yearn to break out of their winter cocoons, we are able to get aboard a little early and do some top deck work protected from fluky frosts and cold spring rains. When it’s time to uncover, our boat can come out with her spreader bars already varnished and other odds and ends complete. The initial effort and expense to build this system has paid us back ten fold. Evolution is good.