Knots for trampoline corners?

[Wanderlust]

I am replacing the trampoline on my Lagoon and would like some ideas on how to tie the corners.

The net material is folded at the edges with 10mm rope woven through those edges and tied to a single ring at each corner. This follows what was previously there, but I want to improve on the corner ties. They were a bit messy.

I assume some adjustment will be needed after a few weeks due to initial stretching, so retying should be possible.

I'm currently thinking of a Taut Line hitch for line A, and tie a similar one for B over/through the loop formed in A. There isn't much space.

Any better suggestions?

[Wanderlust]

Anyone got ideas or done this before?

[belizesailor]

Maybe I misunderstand your description, but Ive never encountered a tramp net with the line sewn in...replacing the line would require unstiching and restiching the net...have you considered replacing with a good heavy grommet in the corner?

Depending on boat details, Ive just used a round turn and two half hitches. You can pull sufficiently tight and hold via the round turn and then just half hitch it off. To adjust, just unlay the half hitches and haul taut again. Leave plenty of tail to work with.

Related note: on beach cats, tramp tensioning is part of tuning the boat and is structurally significant, on cruising cats it is niether. So, you dont need to get these lines very tight, just enough to avoid excessive sag in the tramp.

[thinwater]

I've tied lots of tramps, but not a Lagoon. I was waiting for other responses. However, three things jump out at me, that perhaps a photo would answer:

1. It seems the rope and tramp would be subject to wear where the line exits the hem area. But I have not seen the execution.
2. The deck edge seems to be short on eyes in the corner. I have added a few in the past.
3. The lacing seems to be continuous. This violates World Sailing requirements of being "solidly fixed at regular intervals," because if the line breaks it can zip out, dropping the sailor in the water. It needs to be tied off or locked every few lacings, depending on who you ask, but certainly at least a few places on each side.

As I said, I may misunderstand. Just remember that strong and safe are more important than messy.

[belizesailor]

Originally Posted by thinwater

I've tied lots of tramps, but not a Lagoon. I was waiting for other responses. However, three things jump out at me, that perhaps a photo would answer:

1. It seems the rope and tramp would be subject to wear where the line exits the hem area. But I have not seen the execution.
2. The deck edge seems to be short on eyes in the corner. I have added a few in the past.
3. The lacing seems to be continuous. This violates World Sailing requirements of being "solidly fixed at regular intervals," because if the line breaks it can zip out, dropping the sailor in the water. It needs to be tied off or locked every few lacings, depending on who you ask, but certainly at least a few places on each side.

As I said, I may misunderstand. Just remember that strong and safe are more important than messy.

Those were some of my toughts too, if the line simply runs thru the hem of the tramp then that is a formula for chafe and failure.

[Wanderlust]

Thanks for the response.

To clarify on the construction .... the netting is simply folded over the 10mm line, which is then pulled tight to the rings in the corners. It's not sewn in, but woven in/out of the material to keep it in postion. As per the diagram there is a smaller diameter line that keeps the loose excess folded netting in position.

There is no covering material at the edges so a grommet is not an option.

Also, if I just tie each line directly to the mounting point it will tend to pull the corners in too much. I believe the lines A and B need to be joined and form something like a 45 degree angle.

I wasn't going to post a photo of what I'm replacing because it looks so bad, but this should explain it well. The new material has larger 22mm squares.

Edit: I see a couple of comments while I was putting my response together. I agree with avoiding the single point of failure ... in the plan. There is no sign of chafing in the old one. Once tensioned, there should be no movement. And it's too late for redesign as it needs to be finished tomorrow.

[belizesailor]

Ah, ok, makes more sense with a pic. I have seen that style of netting. I would rig in a similar fashion...just cleaner...quite a mess on the old tramp.

[Wanderlust]

Yes, I think it was a poor attempt to retension the net without doing a full retie. The other corners were not so ugly.

I still don't have any suggestions on how to make the ties and have them looking neat.

[Benz]

I'm writing an article right now on how to do tidy and proper lashings, but I'm afraid it won't be published for a few months yet. In the meantime...
I would splice a loop in each A and B, then lash each one individually with 1/8" twine to the ring in the corner. Deadend the twine at the spliced eyes in A and B by splicing it around, then do all your turns between the eye and the ring, pull as tight as you like, then hitch the tail again and again around the standing legs.

[sv Grateful]

Take a look at http://www.atninc.com/pdf/replace-tr...ihull-nets.pdf for good instructions.

Disregard the poster who said that to doesn't matter how tight you get the net: there is no such thing as too tight!

[Wanderlust]

Thanks Benz and Grateful.

Benz, your solution sounds like it will be quite neat and professional looking which is exactly what I was after. I'm not sure I fully understand what you said, but the concept of spliced loops wrapped with smaller diameter somewhat like whipping seems promising. Due to the small working area I may need to bring the loops right near the eye, and then wrap around the loops. That leaves minimal opportunity for adjustment in the length.

I imagine I will need to unthread the 10mm lines from the netting for some distance so I can make the splices, then weave the loops back through. That should work but with some difficulty. And my splicing skills in double braid need practice. So it will take me some time.

In the meantime I have a fast approaching splash date so needed a quicker solution. I have just used bowlines as a temporary measure but will look at your suggestion when I retension after a bit of use.

Much appreciated.

[Benz]

^^ you're welcome. In the meantime, walk the docks and look at other people's solutions--there's only a few ways to make lashings look tidy; there's lots of ways to make them look bad. Symmetry is everything.