By Alex Crowell
UK Halsey Houston sail consultant

10 steps to building a sail

There are many questions on how complex it is to build a sail. So here is the step by step process from start to finish in our loft located in Kemah, Texas. In this demonstration we are building a vertical batten roller furling main with the Platinum Drive sail cloth. The pictures will show you how much area is gained and how much work goes into our sails. A vertical batten main comes out to about 15% of used sail area. This will increase the boats performance and still have the ease of in mast furling.

Step 1

After the customer has told us what they want to do we are able to customize the sail that will work best for them. In this case it was a Beneteau 411 that will be sailed around the bay, does long range cruising, and participates in off shore coastal racing from time to time. The sail of choice for this application is the Platinum Drive with Taffeta. Even if you don’t race, this is a perfect sail for cruising. It holds shape longer than standard Dacron and will be less likely to tear in rough weather.

Step 2

Measuring the boat is the most important step in building a sail. One design sail boats all have the same measurements and you are able to build a sail without seeing the boat. When it comes to cruising boats and one off race boats there has to be a lot of measuring for a perfect fit. Even if you have a common boat like a Catalina you need to measure for differences from year to year. The plans on that boat may have changed.

Step 3

Ordering the cloth of the correct weight is next. We order the Tape Drive skin (cloth with tapes on) out of San Diego to keep up with production. When the skin shows up, we measure and check the old sail against it. In this case you can see the extra sail area gained by adding vertical battens. Also, remember the luff curve on the old main and watch for the difference of the new main later on in this build. It will show how stretched out a sail becomes, hurting a boats performance.


Step 4

We are starting to lay in all of the corner patches for extra strength and durability. After the patches are glued down they will also be stitched. Extra reinforcing is added to the leach and foot of the sail at this point. This adds more stability to an already rigid sail.

Step 5

We measure the sail for Batten placement. After we have measured we add more reinforcement to where we are going to add the battens and the leach line. This will help with wear over time. All the pockets are built then they get glued and stitched to the sail. The leach line is added by stitching a tape over it for sail adjustment.


Step 6

The luff curve is set and it is time to add the luff tape so we can attach the sail to the furler. This determines allot of the sails characteristics while under sail. If you do not set the luff curve the sail would be possibly flat or baggy depending on mast bend. In this case it is a roller main so it has a fairly straight mast and will need less of a curve. You can see in the picture below. Remember how much the old sail had stretched.

Step 7

The head and tack are finished with a webbing eye. The clew has a block added for the out haul. We upgrade the block to a Harken as you can see in the picture. This will help the sail furl in and out and be more reliable than the old block that comes with the original sails.



Step 8

All of the final finishing touches are completed. Trace and cut new logo from sticky back, Add draft stripes and leach line cleat, and last but not least add the most important thing, the UK Halsey logo.


Step 9

Now for the test fit. During this process you check to see if all the measuring and work that has been done is correct. If not you would have to drop the sail and fix any problems. Once again it is a perfect fit. From the photos you can see all the shape that has been and the positive roach that has been added.


Step 10

Now to check to see how it furls. Notice as we furl the sail it keeps shape. This will help as the wind builds. Also notice there isn’t any bunching that would cause the sail to not furl correctly. This is when you test time and time again for problems. In mast furling with battens, who would have thought it was possible?

Going Going Gone


Fun Fact

You can add 15% more sail area with more strength and it is a lighter sail. Here is the proof. Any questions?


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