PDRacer Sailboat

Back to main page

There are many materials that people have made cheap sails from, such as old bedsheets, raincoats, construction plastic etc. One of the best materials to use is polytarp, because it does not stretch that much retaining it's shape, and you can buy good sized polytarps for very low cost, such as the 12' x 16' tarp used in this essay that I bought for $9. There are many methods for making the polytarp sails, this is easiest and fastest method I have found.

Make your spars first. This sail is a high peaked balanced lug sail. You can get a rough idea of how big your sail will be by tying line to your spars and stretching them out on the tarp. This will let you cut away the excess tarp, so you only have to work with a piece that is slightly larger than your final sail.

Use duct tape to stretch and hold the tarp to the ground.

Draw the perimeter line of your sail on the tarp. This sail's draft is being shaped with the curved luff and foot method. Well, since it is a 4 sided sail, it has a curved head and foot. You can either draw a nice curve to it, or you can use slightly less effecient straight lines like shown. (see essay on shaping sails)

The leech is made by laying a single piece of duct tape along the inside of the line. This will be the aft edge of the sail. We just want one smooth strip of tape back there, so the air can flow and escape from the sail in a smooth motion. You can either use a single piece of tape on one side, or put a piece on each side of the sail.

The head, luff, and foot all are going to have a "bolt rope" sealed in their edges. We start by laying a strip of double sticky carpet tape centered on the perimeter lines.

This is is a good time to press the tape down on the entire perimeter. Some people use rollers, some hammer their edges, I use my bare foot and slide it along pressing as I go.

At this point we have tape all along the entire perimeter of our sail.

We can now cut away the excess material.

Time to install the bolt rope. Most polytarps come with a small line along the entire perimeter. It is made from a low stretch synthetic materials and is excellent for bolt rope. Cut the line out of the scraps that you have already removed, and make a loop in one end. Start at the peak, and lay along the middle of the carpet tape.

Fold the tape over as you go sealing the rope along the edge of the sail. Do this on the entire head, luff, and foot of the sail, ending in a small loop at the clew.

Lay down duct tape over the remaining seam.

Our sail is almost complete.

Instead of using grommets, you can use a soldering iron or other pointy heated object (like ice pick or screw driver heated with propane torch) to poke holes along the edges. The spacing is up to you, I prefer to put them 10" apart because that is the distance from the tip of my pinky to the end of my thumb while my hand is stretched out. Some people lace as close as 6", others as wide as 12".

Zip ties are a simple method for attaching the sail to the spars. Another good method is to use 2 spirals of line, in opposite directions. That way, if you run into trouble and break something on the water, you can remove one of the spirals for use making repairs.

Presto, with about 1.5 hours worth of work, you have a completed sail.

Be careful to keep the duct tape dry, don't abuse it, and your sail should last a for a while. When it breaks beyond repair, you only have to spend another 1.5 hours making another sail, or if your sail has proven to be a good one, consider making (or having one made) from dacron.

There are many other ways you can construct polytarp sails. A stronger method is to use clear packing tape to hold the seams, and then sew the sail with a sewing machine. After sewing, you can remove the clear tape. You also might be able to sew through the duct tape if you lubricate the needle with vasaline.

Not just for pdracers, polytarp sails have been seen on many different sailboats such as Cap'n Freddy's sloop. This photo is from Craig O'Donnell's Cheap Pages, where you can see other neat sails made from polytarp.

You can even buy white polytarp, so people will think you have a regular dacron sail.

Back to main page

Home