March 2014 – Updated post on jerry cans here.
Once you’ve found the best jerry can* to store extra water and fuels, you want to protect them from the sun and elements as they wait their turn to provide us with the reserves they hold. Enter the canvas cover. We’ll be making covers for so many things on the boat. This is a good basic project – no zippers or complex patterning. It’s an upside down tote bag or box. Sides and a top. Make a plan and think it through before cutting. Disclaimer: I haven’t made these myself yet but I’ve been reading up on them as they are in my near future. This is based on information from Canvas for Cruisers and other references and experience.
You need about 1-2 yards of Sunbrella or similar outdoor acrylic fabric depending on size and plan and good UV resistant thread (V69 or 92) to match. You could start with a mock-up in inexpensive fabric to get a good test fit.
Make the base. Basically you want to wrap the fabric around the jerry can and add 1″ for the vertical seam which will be sewn 1/2″ wide to make the base. Don’t make it too tight around. It should be easy to slip on and off and allow so air to circulate when it’s on.
For the height of the can be sure to add 1/2″ at the base for a hem if you can seal the raw edge and another 1/2″ for the seam at the top. The hem should not touch the deck.
Secret tip: If you use a hot knife or soldering tool to cut the fabric it won’t ravel and you won’t need to turn a hem under twice or edge the seam. If you don’t have a way to seal a cut edge, zig zag the edge or use pinking shears if you have those. Sunbrella ravels a lot. If you don’t address the ravelling now, you will have a change to address it later! Add an inch for a raw edge that you zig zag and roll under twice.
Go ahead and sew the side seam of the base and don’t forget to add a few stitches in reverse as you begin and end the seam to lock it.
Cut the top. Make it as long as the can is plus 1″ for the seams. For the width take the measurement of the width plus the extra height of the handle plus an inch for seams. You might benefit from making a mock-up out of muslin or paper to make sure you have enough. I’d go a bit generous here. You can take up extra in the seams or hem if you need to. It shouldn’t be too tight though. Staple or pin this on right sides together (turn the base inside out when you slip it back on.) There will be extra fabric at the corners. Take this and pinch it together forming a dart. Staple or pin these four darts. Take your cover to the sewing machine and sew the darts and then the top on to the base. Sewing a dart is just sewing from the wider outside edge to the point. Trim the wider end to 1/2″ and seal with hot knife or zig zag edge.
Turn the cover right side out and slip it on. Measure and mark the hem so that it won’t touch the deck or ground. It should be around the 1/2″ you measured but if not you can make it and take it back to the machine and sew down the hem by stitching 1/2″ from the bottom edge.
The basic cover is done. You may want to tailor for securing the cover to the can with straps or for securing the jerry can to the boat.
*If you give up on covers, rethink your water storage container! Lin Pardy says in The Care and Feeding of Sailing Crew to buy black plastic jugs because they don’t degrade in the sun! She also recommends flexible bladders or folding water jugs from Reliance Products to hold extra water and store in the bilge (think sun shower type products).
Gallant Fox adds a cover for the spout.
Stella Blue adds grommets for lashing them to stanchions.
Julie Gifford suggests a cut out for the handle by marking the handle opening on both sides of the top and turning the edges under and sewing them down. You’ll need to make small slits at the corners. Add a flap sewn on one side and velcro’d on the other. Make the flap by cutting a length of fabric to fit across the top, the width should be twice the area you want to cover plus 1″ for seams. Fold in half lengthwise and sew down the one longer side. Turn it right side out. Stitch it to one side of the opening right sides together. On the other side opening, add velcro to the underside of the flap. Add the other velco to the right side of the base. If you use sticky velcro or double sided seam tape, you can put the velcro sides together and attach in place then separate the velcro and sew in place.
If you are using Navy or Captain Navy Sunbrella, use black thread. Thread will likely degrade and discolor before the material unless you are using Gortex.
If your machine doesn’t have measurements on the face plate, measure 1/2′ from the needle and put down a few inches blue painters tape or masking tape at that point so you have a stationary mark. You can use a magnetic seam guide, but it can get in the way.
You can use a stapler to “pin” the seam if you don’t have heavy T-pins. Regular straight pins are tough to use on Sunbrella.
It would be great to hear other experiences and ideas for improving jerry can covers.
Julie Gifford’s Canvas for Cruisers (see Books page) has great detailed instructions.