Trimaran: netting/trampoline attachments

Has anyone added netting and/or tramps to their tri or cat?

We're thinking about tying our own nets for the space forward of the forward beam, and using good shade cloth for the tramps between main hull and amas.

Making the net is a challenge (what rope, what knot?) and fixing both the net and the tramps to the tri in an elegant way is also difficult to picture.

Thanks,

Danny Bishop
Wellington, NZ

 

How about flat nylon webbing? Sew or grommet together where they cross each other. Connect to a metal rail attached on the boat perimeter, or use mechanical connectors to connect to a series of deck fittings around the openings.

 

I like the flat webbing idea. Sew and rivet/grommet the junctions, and for the ends, a metal rail will look nicest (and probably be stronger than securing each strap separately to the hull).

 

have a 65 foot tri, the tramps are secured by having ss saddles every 6 inches through bolted on hull around perimeter of tramp. then a ss cable is passed through saddles and tensioned at each end.across the fwd section is another ss cable strung between hull and ama this is connected to very strong through bolted pad eyes. the tramps are then laced to the ss cables. advantages is that the cables tend to slide through the saddled somewhat and even out the load when you stand at the edge of the tramp instead of one or two saddles taking all the load. tramp material is avail from www.sailrite.com have used "cod end" fishing net in Australia on 40 foot cats and it looks quite good. saddles to hull again, then three strand rope spliced to form a loop. lace loop between hull and saddles with about a 3 inch gap then lace net to rope. cheap neat strong and allows water to pass unobstructed. if using webbing, saddles to hull then high pressure pvc pipe laced around inside of hull 3" off. weave webb at about 45 degrees from side to side front to back so each cross at about 90 degrees(exits pipe around hull at 45 degrees) once all in place and looking good hot melt glue where each webb crosses. carefully remave tramp then machine stitch fully along both edges of all the webbing. very strong but can be expensive. takes a whole lot of webb.

 

One of the slickest ways I've seen of attaching the tramps to the hull is to glass in a PVC tube all along the hull or beam where you want to attach the net. Then cut/grind away a portion of the tube at intervals where you want the net to attach. A fiberglass rod is inserted down the tube to thread through the loops in the net, or to take the lacing from the net.

The glassing of the tube transfers all the load to the outer skin, of course. If you wanted to really nail it to the hull, you could drill all the way through above and below the tube, then run unidirectional tow through the holes from outside to inside and back out again to tie the tubes to the structure. Once the tow and holles are filled with resin, there would be no leaking into the boat or the core.

This method requires no hardware or fasteners, and is lightweight. Not to mention cheap. Looks good, too.

 

I should have thought of that, Tom. Brilliant idea. No metal to corrode, no bolts to trip over, no sharp rail to chafe lines on. I like it.

 

I really like Toms idea, but here's another.....
On my cat, I have teak rails about 3/4" X 1.5" , like handrails with the openings being about 2" x 3/4". where the rail is full thickness there is a screw holding this rail to the hull or wing.
As for netting, the flat webbing is best and most comfortable and at the bow you want the water to pass through quickly. So, to attach the netting to the rails, I run a PVC pipe through the edge of the net and lace the net to the teak hull rails. By lacing to the PVC, you save your nets from chafing through. This is a fairly common system, but I think next time around, I'll follow Tom's recipe.....