4 Sided Sails For The PDRacer Sailboat
In the picture the boat on the far left has a lateen sail, the one in the middle has a balanced lug that uses a high angle yard. The blue boat on the far right has balanced lug more of a moderate angle yard.
The balanced lug is a very popular type of sail used on home built boats. They are simple to make, simple to use, and puts a lot of sail area on a small set of spars. Basically it is a 4 sided sail that has a stick on the top edge (yard) and a stick on the bottom edge (boom). You hoist it from a line tied to the yard. Both the yard and boom extend both fore and aft of the mast, and so it is called a "balanced lug", even though it really isn't balanced on the mast.
One of the things I have noticed about balanced lug sails is they can be made in a variety of shapes and sizes. The yard angle is a big variable that various people employ to get a certain look from the sail. The picture to the right is Marc Blazer's #173 "Bloody Splinter".
While balanced lug sails are very popular to use for recreation, they are not the most competitive sail for racing. For more info, see a comparison of 3 sided VS 4 sided sails on the sailboat racing and performance page.
Standing Lug With Jib
Also 4 sided like a balanced lug sail, has a yard up top, but this sail rig has the tack (forward bottom corner of the sail) attached to the mast.
This sail also has a leech that is rounded outwards with battens to stiffen the trailing edge, it is a trick to get more sail area and help the laminar flow as the wind leaves the sail. This rig also has a jib. This is Joel Rodgers #703
Basic Rectangle Standing Lug
This is a very simple version of the standing lug, easy as can be, it is made from a rectangular tarp. This is one of Jason Nabors's boats #31
Sprit Sail (4 sided, traditional)
This rig has the sail laced to the mast, and a stick that goes diagonally up to hold the peak of the sail. This one has a sprit boom also, but sometimes the sail is used without a boom.
As you can see in this picture, you can even use a perfectly rectangular tarp for your sail.
This sail has it's leading edge (luff) attached to the mast, and has a stick along the top (called a yard).
This is Gordon Seiter #58, note that his duck also has a jib sail attached forward of the mast. If you look a little closer, you will see it has a bow sprit made from a hockey stick. Hehehe....