Winter Cover

Work has begun on a winter cover for Ariel. With my wife’s blessing and some extra cash from Jake’s piggy bank – college isn’t that important, right?! – I phoned Sailrite and placed an order for their Deluxe LSZ-1 PP zigzag/straight stitch fancy-shmancy sewing machine and forty yards of Surlast fabric. Now, a week or so later, I’ve constructed the ridge pole – Ariel is mast up this winter – made my measurements, and begun sewing the panels together. So far things are looking good. It’s too bad we didn’t get an earlier start on the cover, but it took some mental preparation (and scraping) to order the machine and fabric. So, now it’s a race to get Ariel covered before winter wreaks her havoc.

An In-Progress Account of Constructing a Winter Cover:
1. Construct a ridge pole that will support the winter cover and provide enough pitch to easily shed snow.
a. Based upon the design of other – professional – winter covers at our marina, I decided to locate the ridge pole approximately level with the gooseneck (Ariel’s boom is off, although some boat covers are designed to utilize the boom for support). This height creates an adequate slope and yet is low enough to avoid excessive windage, which was a concern since we get some fierce winter storms with high winds here in Michigan.
b. Several 2x4s with overlapping joints were screwed (scabbed) together to span the distance between the aft edge of the mast and backstay, and the forward edge of the mast and the headstay. I sandwiched the stays between the ridge pole and a scrap of wood with thru-bolts to hold the ends in place, being careful to not to apply too much clamping pressure on the stays.
2. Begin preliminary measurements and design work:
a. Using a hull diagram from the CD36 manual for my schematic, I took some rough measurements:
i. boat length from stem to stern, including bow and stern pulpits
ii. distance between the backstay and the aft edge of the mast along the ridge pole
iii. distance between the headstay and the forward edge of the mast along the ridge pole
iv. distance from the mast to the stern and bow pulpits
v. distance from the ridge pole centerline* to the lifeline tops at five** foot intervals
vi. distance from the lifeline tops to the rubrail
vii. distance from the rubrail to the bootstripe
b. * My plan was to run the fabric panels perpendicular to the boat’s centerline. Doubling the measurement from ridge pole centerline to lifeline top provides total panel length (plus seam allowances) at each interval.
** I had already decided that I was going to use a fabric that is 60” wide when I began taking measurements, hence the width measurements at five foot intervals along the ridge pole. Any other fabric width would require measurements at corresponding intervals.
c. I sketched the several panels on the diagram and calculated their total length plus seam allowances.
i. After consulting Don Casey’s Cavaswork and Sail Repair, I decided to use flat-felled seams for all the panels. Not only is the flat-felled seam better looking – and a must in areas without selvage – but I thought it might be a stronger stitch than a simple double- or triple-sewn 1” overlap. This type of seam is undeniably more work, but the finished look and hopefully added strength are well worth it – not to mention all the experience I’m getting!
ii. Flat-felled seams with an initial 1/2” overlap result in 1” of fabric used per seam. When joining two panels, this means that each 60” panel width – actual measurement is 60.5” – is only 58.5” in its finished width. The finished width measurement must be used when determining the number of panels necessary to cover the length of the boat. In my case, this amounted to 7 full panels, plus bow and stern closures.


Flat-felled seam - total of four layers of fabric with initial overlap folded over on itself.
iii. Regarding the length of each panel, I added 2” to each measured panel length to account for the flat-felled seams that will join the cover to the side panels.
iv. To this point, the cover only spans the “topside” dimensions of the hull and does not include the material needed to span the distance from the lifeline tops to the bootstripe, or other arbitrary ending point. With a distance of 26” from lifeline top to rubrail and an additional 30” to the bootstripe, I chose a finished length of 48” for the side panels – although I may choose to extend this as I progress. Regardless of my final length, I must add 1” for the seam that joins the side panel to the cover, and 1 ½” for the final hem that will enclose a drawstring to conform the cover to the hull contour.
v. All that said, I estimated my required yardage to be around 40. As the project nears conclusion, I’ll find out just how good of an approximation that is. In the meantime, I’ll keep my fingers crossed.
3. Begin cutting the panels according to the longest length necessary in each panel. Due to the shape of the boat, it is likely that the panels will be irregular, with one end of the panel longer than the other. For example, one of the panels for Ariel is 146” long at the forward edge and only 130” long at the aft edge. This means that my minimum panel length must be 146” if I am to have enough material to span the hull at that point and match the adjoining panel properly. As the panels are cut, ensure that the edges are square to avoid uneven seam lines later on.
a. With two panels cut, mark the center of both panels.
b. On one panel mark a series of marks along the panel’s length ½” from the edge (or selvage). These marks will be used to locate your overlapping panel.


Marking the panel edges with a 1/2" margin prior to basting.
c. Apply basting tape within the ½” marks along the length of the panel.
d. Align center marks on the two panels and begin adhering the two panels together, working from the center out, and aligning the overlapping panel with your ½” seam marks.
4. Sew the panels together using a 6mm straight-stitch. Sew a single stitch down the center of the seam, locking both ends by backing up over the stitches.


Straight stitch right down the center of the basted seam.


Locked stitches at both the beginning and end of a seam.
a. Handling a substantial length of material can be difficult, especially as three or more panels are sewn together, so rolling the panels together like a scroll can help with feeding the material through the machine as well as keeping the seam flat and wrinkle free.


Panels rolled to ease feeding through the machine.
5. Flat-fell the seams using the same 6mm straight-stitch along the exposed fold.


Sewing the first line of stitches along the fold
6. Sew another stitch approximately a ¼” from the first row of stitches to capture the fold on the inside of the cover.


Second stitch in the seam finished.


"Captured" inner fold during second row of stitches in flat-felled seam.
7. Continue sewing panels together. Depending upon experience and confidence, it may be wise, after sewing together three or four panels, to test fit the cover and mark the cutouts for the mast, shrouds, and any other obstruction rather than assembling to whole thing only to discover that your measurements weren’t quite right and cutouts need to be relocated or otherwise modified.
8. Once all of the panels are sewn together, spread the cover out flat on the floor and mark out panel lengths. Draw a fair curve using a long batten to reproduce an outline (approximation) of the hull shape. Cut along outline.
9. Fabricate panels for bow and stern enclosures.
10. Fabricate vertical panels that will conform to the hull’s sides.
11. Sew in hem for drawstring along panel bottom.
12. Sew webbing attachment points for tie downs.
13. Sew in reinforcement patches for ridge pole and lifeline tops.
14. And….experience will show me what I’ve overlooked!