Drafting film sails

Good day ladies and gents

I want to find out what is there to know about using drafting film as a sail material.

Is drafting film the same as Mylar?

Is it just a question of cutting the sails out according to a flat plan and leaving some extra overlap for joining the panels with double sided tape, or do the sails need to be curved?

What is the best way to attach the main sail to the mast?

Can drafting film be painted, and if so, what paint will work, be flexible and not flake off the sail?

How do I reinforcr corners to take the tension of the lines and not tear?

I am planning on scratchbuilding a 120 Amerca’s Cup, and have 50 micron (0.05mm) drafting film available. Any advice would be appreciated.


PS: I have read through all the sailmaking threads on this forum, and gathered a load of info already, but these points are not very clear to me.

As far as I know, drafting film is just a frosted finish on mylar sheet, so yes.

The idea is to take several flat panels of mylar, and join them with double sided tape where the edges of the panels are on a curve. When the leading edge of the sail and the trailing edge are tensioned, the middle of the sail will have extra fabric and will hang down, giving it an airfoil shape. getting the curve at each seam is the hard part because the seams are so short and the amount of curve is so slight. Here is where a broadseaming block comes in.


Click the “Library” link and then look for the several links on sailmaking. This is an excellent resource for anyone wanting to give it a try. With a little patience, you can make some very nice sails.

I attach the sails to the mast by tieing them on with spectra fishing line.

No paint will stick to mylar, heck epoxy won’t stick either, but majic markers do OK. They will fade over time in the sun though.

To reinforce the corners, use dacron “stickyback”. Any sail loft will have some, and Midwest Model Yachting dot com has different colors (but they are not answering emails or shipping orders now for some reason). ONce the dacron strips are applied, you can either insert a small grommet, or heat up a wire and melt a small hole in it. THe heat will melt a nice ridge making it’s own grommet.

Gidday Adam,

Ben Morris in Australia http://members.iinet.net.au/~benmorris@senet.com.au/saildesign/sailshape.htm is a wealth of information and his step-by-step instruction is fairly easy to follow, I’ve made several sail plans using his method and extremely happy with the results.

Welcome to the AC 120 club, I have bulit two so far you can see in Americas Cup section under ETNZ dual build, lots of people here can give you help with good advice, you should also visit the Italian site (if you have’nt already) which is the beginnings of AC 120, there is an English forum there and really helpful people. http://iacc120cup.altervista.org

Looking forward to seeing your build progress.

Cheers Alan

Thanks for all the help guys.

Thanks for the link Alan, just what I was looking for. The rest of the links I’ve already saved under favourites.