Modern Spar building with epoxy?

I am going to be building a box section wood mast and boom soon, and am looking for resources on using epoxy and modern techniques. Does anyone know of any books, websites or examples of wood masts built using modern epoxy methods.

Thanks, Cody

 

Get the WEST system brochures on wooden boat repair at any dealer of the products. This will give you a good start in understanding the materials. In general, spar building with epoxy is no different than other glues EXCEPT one should use little clamping pressure, unlike Weldwood or Resorcinol. Epoxy needs some glue thickness to work. Use the 'laminating additive' which I think is fine chopped cotton fiber. I built a boom many years ago this way and it's still near perfect.

 

Log onto www.westsystem.com and www.systemthree.com and download their free user's guides. These will cover basic methods, materials and techniques.

West System (and others) have a host of fillers that can be added to the epoxy, to impart some physical properties. Cotton flock is what Bataan is referring to, and it's called 403 (West 403). This is a high density filler and fine for bonding things, but will need some help with a spar, so add some 406 (silica) to control viscosity.

Download the Gougeon brothers book on boat building, from the West System site (it's free) it will cover the techniques in much further depth, including spar making.

 

Box masts and booms are simple and easy to build. The most challenging part is to get them straight. A little planning and care is all it takes.

You might want to consider a birds mouth construction or at least take a look at the method. You can use the search function here, or on Google, to find information. The birds mouth spar is nearly round, rather nice looking, and might even be a better marriage for your sail. It is a little more complex but probably not beyond your building skills. The hardest part of either method is to find suitable straight grained wood in appropriate lengths.

 

Birdsmouth spars can be completely round, faceted or oval. One of the nice things about birdsmouth doesn't need long lengths of straight grain lumber. It can be approached with lesser grades and shorter lengths, all glued together.

 

This may interest you.

http://www.idniyra.org/articles/mast_made_easy.htm

 

The DN mast is interesting, but considerably more complex than a box or birdsmouth section.