Carbon Reinforced Wooden Masts

Jan has made most of his masts with laminated spruce or douglas fir veneers. He uses five 1/16" thick pieces. He vacuum bags them into mast halves. The mold for vacuum bagging was made with fiberglass on a Norton wing mast. Jan chose this method because he has the veneer in the shop and has the vacuum bagging equipment available as well. His mold was made from a slightly kinked mast so all his wood masts are a little asymmetric.

Vacuum bagging is quick and easy way to make a bunch of mast halves. There is a good article on the subject in the a recent issue of the Boatbuilder (Number 25), the Gougeon brothers Inc. newsletter. If you are going to get together with a few friends to make a bunch of masts, vacuum bagging might be a good choice. Jan feels that from a technical point of view that the strip method should result in as good a mast.

Jan's masts have evolved over the years he has been making and sailing with them. His current masts are about 2 1/4" to 2 3/8" thick at the base. That thickness is kept for the first two feet or so. The thickness then tapers to about 2" at the hound and to about 1 7/8" at the top. This keeps the maximum bend point a little higher on the mast. This makes them less prone to breaking. Jan also feels it fits the sail better.

In the nose and tail he uses the carbon schedule shown on the mast plan in the Gougeon DN plans. The purpose of the carbon here Is to make the mast stiff enough in the for and aft direction to make it useable with sails cut for aluminum masts. The use of an aluminum luff tube (as allowed by the new mast specs) will provide a fair amount of stiffness to the trailing edge.

He is finding he can use less carbon in the sidewalls than is shown in the Gougeon Plans. Jan sees the main advantage of carbon fiber is it makes it easy to tune a mast to the proper stiffness. He suggests trying to make it a lime less stiff than desired and then add a tow or two of carbon to the sidewall to bring it up the right stiffness.

Nobody I have spoken with so far has been too specific about what the right sidewall stiffness is. Almost as stiff as a good aluminum mast is a good starting place. Obviously how heavy you are and your sailing style have a lot to do with optimum stiffness. A softer mast is more manageable to sail. Mike O'Brien likes masts that are even stiffer than fast aluminum masts.

Jan has been experimenting with masts that are shorter than maximum. This allows him to stand the rig up a more and to keep the sail lower.

Jan uses a standard Sarns halyard tube. He bends the tube to fit. He flares the sail end with something hard and pointy. This will minimize the tendency of the halyard to fray. Jan also suggests considering a 1/8" halyard to minimize the chance of halyard failure during a regatta. He also waxes the cable to lubricate it. He makes a horizontal wrap of carbon around the top to make it stronger. He does the same thing around the bottom.

The hound is reinforced with glass or carbon. These wraps may be more than one layer thick. Be careful about not exceeding the maximum mast dimensions.

Jan had some other suggestions for setting up the mast and the rest of the boat. That will be the subject of another article in a future newsletter.

Joe Norton has a quick method for making strip masts. He lays the mast upon an aluminum mast with the hound and any other interfering hardware removed. Joe says this is a fast and easy way to lay up a mast. The first strip is taped (with duct tape or what ever works) to the mast about 3/4" from the trailing edge. Additional strips are added until to about 1/4" to 3/8" past the center of the front of the mast. The mast and strips are then spiral wrapped with a piece of shock chord to hold everything in place. The wraps are about 12" apart. Epoxy and microballoons are squeezed into the gaps between the strips as much as is reasonable with out getting the mixture on the shock chord. The rest is filled in after the shock chord is removed. He didn't find it necessary to wax the mast to give release to any epoxy that squeezes through the cracks between the strips. On the other hand, waxing wouldn't hurt. car wax works well.

The strips in the back are about 3/4" wide and 5/16 inch thick. The strips get narrower foreword, becoming almost square at the front. Joe used different woods in different parts of the mast. He uses ash or oak in the nose and tail and a strip of the same at the maximum thickness. He prefers ash to oak. In between he uses sitka spruce strips.

To adjust the thickness Joe uses a joiner. He found this does a good job very quickly. (The ends of the halves are supported during this process.) He uses the joiner to make the luff slot by making a couple of Dashes along the trailing edge.

For a web in the back he uses two trapezoidal shaped Pieces of wood. one piece is Cued to each half. They are Sued on perpendicular to the calf at the attachment point. The joiner planes the edge of the Knob piece so it will be flat on the other half when they are glued together.

The inside of the halves are fiberglassed with two layers of Sass cloth. The first glass layers put into the bare half before the web piece is glued in. The second layer is put in after the web piece. It extends up onto the web piece.

Joe has been using Orcon carbon fiber. It comes in a 12 inch wide band, held loosely together with a few cross threads. He finds it easy to candle He puts one strip about 2 to 2-1/2" wide in each half. He doesn't put any additional carbon in the nose or tail for and aft stiffness. He said he wasn't sure that fore and aft stiffness was necessary He also said he Wasn't winning the North Americans either.

He also puts a single layer of he full 12" width of carbon at the hound position to strengthen that area. This wide piece is run horizontally. It is put in so it will be about 6" above and below the center of the hound. I am not sure where to buy Orson fiber. Call Joe to find out. I think Henry Bossed may sell it.

For a hound Joe has been using internal aluminum mast rounds he gets from William B Sarns co. Note that this is different than the hound Sarns makes for old style wooden masts. He bends the backing plate on the hound a iiale to fit he beds the hound in epoxy Mash by gooping up the hound before he puts it in place. Joe reinforces the hound area with the internal 12" band of carbon described above. He reinforces the outside with two horizontal wraps of 1" carbon fiber just above and below the nose of the hound. Each of these wraps is three layers thick. He has had no failures at the hound with this method. Jan has also used some similar hound arrangements.

Joe feels than many people are intimidated by the prospect of making a mold and laying up the strip halves. This method makes that part of mast making easy and quick.

George Long sailed to sixth place in last years North Americans with a wood mast that has been described as two ash boards that were hollowed out in the middle and shaped on the outside.

George used very little carbon in this mast. He commented that he doesn't think carbon is necessary. He has made a couple more masts over the summer. One of them has no carbon at all. It has more fore and aft softness than an aluminum mast and is at minimum thickness and maximum width.

George makes his masts with various woods. He uses spruce ash and hickory. While he wasn't specific about the construction he said there is nothing magic about what he is doing. He says it simply a matter of common sense. He did suggest avoiding wood with knots in it. He found hickory was difficult to work with. He did not feel it did enough for the mast to be worth the trouble.

The only special tools he used are a dado blade on his table saw and a hand power plane. His masts are a little heavier than carbon reinforced strip masts. They are simple and based on last years results, fast.

George pointed out that success on the race coarse depends on paying attention to everything, not just one thing. If you have the best DN mast ever made it won't make you fast if everything else isn't right.

These are three approaches to making masts. There are certainly other possibilities. If you have information on what has made a fast mast for you please send it to me for publication in future newsletters.

One last point; Dan Connel came in tied for second at the North Americans with a normal aluminum mast. Mike O'Brien won the Worlds with one.