How to Install Mesh Nets On Multihulls


Mesh nets are made from woven and knitted materials that are the most comfortable of all netting products. All mesh nets are cut to shape and finished with a sewn on border for attachment to the boat. Because of this they can be made to fit a wide variety of shapes with lots of attachment options. The borders on mesh nets fall into 2 general categories; tensioning, and non-tensioning. The different meshes have limits as to where and how these different types of borders can be used and still obtain a good fit with acceptable tension.


Border Type Limitations

The simplest way to make a net is to have a tensioning border like grommets with lacing line, on all sides. By using a non-tensioning border, like boltrope inserted into a track, the amount of lacing can be reduced and the lacing gap eliminated on that side. The following paragraphs describe the minimum number and orientation of tensioning sides for each of the meshes.

The Woven Polypropylene Mesh, due to its wide width and ease of fabrication is the most versatile and can be made with only 1 tensioning side. The remaining 3 sides can be non-tensioning. It usually works best to tension from the widest side. With 2 non-tensioning sides Polypropylene Mesh can be made to fit with the tensioning sides opposite or adjacent of each other.

The Square Hole Mesh is also a woven product, but because it is available only in a relatively narrow width (70") the Square Hole Mesh will need to lace on at least 2 sides and they should be adjacent of each other.

The Coated Polyester Mesh is available in a larger width, but because it is a knitted mesh it will need to be tensioned on at least 2 sides. If it is only tensioned on 2 sides these sides should be opposite each other.


Mesh Net Border types

Tensioning Borders

Grommets laced to attachment points on the boat are the most commonly used method of tensioning mesh nets. Typically we use #4 nickel plated grommets with spur washers set into a stiff reinforcement. The key element in supporting the net with grommets is to disperse the loads from the grommets evenly into the netting. to accomplish this we strongly recommend spacing the grommets no more than 6" apart.

 

Wrap around grommets, where the mesh wraps around a beam on the boat and grommets along the edge of the wrapped mesh lace back to a second row of grommets under the net, can be used to tension the net without a lacing gap.

 

Pipe Sleeves can be used as a tensioning border with lacing points further apart than 6". A rigid rod or tube is inserted into the sleeve and the lacing line laces around the rod through cutouts in the sleeve. This type of border places the loads entirely on the stitching, but we always cover this with the second ply or a separate seam cover. This works well on straight sides but not on curved sides.

 

Webbing Tabs sewn to the underside of a reinforced border to be laced to the boat are another type of tensioning border. Usually a strong tube webbing sewn in a V shape completely under the border so the webbing is not exposed. This is the lightest tensioning border but seldom used as the webbing can chafe and the stress is entirely on the exposed stitching holding the tabs.

 

Non-Tensioning Borders

Boltrope borders have a rope sewn into the edge that is then inserted into a track attached to the boat. It is important here to match the proper rope size with the track Inside diameter so that the rope does not pull out. This is probably the mos common type of non-tensioning border. Mast Section type crossbeams can usually accept a boltrope or we have 2 types of aluminum track available that can be attached to the hulls decks or beams around the net opening.

 

Cable Sleeves can be sewn into the net to accept a cable that spans the edge of a net opening. Cables should be used only if there is no solid structure to attach the net to as they will reduce the firmness of the net. Our cable sleeves are curved to match the catenary curve of the cable under tension. It is not desirable to have more than one cable side on a net as it is difficult to get a good fit and tension the net. Stainless Steel Cables should coated or run through plastic pipe to avoid chafing of the net.

 

Bar Sleeves are large sleeves sewn into a net that fit around a beam attached to the boat. In order to install this at least one end of the beam must be removable to insert the net onto it.

 

Unsupported or Self Supported borders can be used on smaller nets or in corners or cut-out areas of larger nets where their is no structure or hardware to attach to. A strong polyester webbing is used in the border and the net is cut with a large catenary curve. This webbing becomes similar to a cable, and like cable the loads at the ends of this side will be much greater than those along supported sides. The corners of this border should be laced to strong, through bolted attachment points. Obviously this type of attachment used to support an entire side of a net will offer less support, and the net will not be as firm. However if the net is not expected to receive much traffic this can be a more economical solution than a cable.