multihull nets

[skipperpete]

Originally Posted by HeywoodJ

We have Ultra Cross netting on our catamaran, will provide the same caution I did in the last thread on this subject - there is no give in UHMWPE netting.



We love our tramps, but they are not tramps. Used to be we had kids come over and play on the nets, bouncing around. There is no bounce with UC. What does it matter you ask (and, indeed, this is one of the great things about these nets when handling an errant sail, in the rain, at 0-dark-thirty)? Many multihull attachment points are not built for the increased stress of a very-low-stretch net. When you jump up and down on a bouncy tramp the elasticity and stretch distribute the load at the edges quite widely. With a UHMWPE net when you fall on the net the load is transmitted directly and immediately.



Not saying don't use them, we love ours, but be cognizant of the changed loading aspects for the attachment points. Have seen several failures directly related to changing to low stretch netting.

The net I’m about to remove/ repair/replace is secured by bungee cord around the entire border so the bounce comes from that, and at the moment the old shock cord is looking very shabby. I was more concerned with how a knot less Dyneema net would feel under bare feet.

[freeden]

Hi fxykty if you go to their website and click on "products" then click on "multiuse line" under the cruising header then click on "nets for catamarans" and scroll down then it will come up

[freeden]

skipperpete when I was trying to buy the net I rang hampidjan and they told me they dont sell retail, so I had to go through the supplier in nsw. so I am surprised that you can buy direct from them?? If you can you may get a better price than I did so good luck.

[freeden]

Hi Eric Jan the way I am going to attach the net is by using a bolt rope around the perimiter and thread that through the net and use that to attach to my deck
I hope that makes sense.

[Eric Jan]

Originally Posted by freeden

Hi Eric Jan the way I am going to attach the net is by using a bolt rope around the perimiter and thread that through the net and use that to attach to my deck
I hope that makes sense.

Yeah I think I get it - look forward to the results.

We are up for a new net coming winter so either this or from sailonet a pre-fab from la rochelle, france.

[Franziska]

Regarding using elastic bungee Cord for attachment, Im very skeptical on the longevity. Never had elastic in other applications lasting over years outside under UV, saltwater, and permanent stretch.
Has anyone really done that?

Our net current net is tied to individual ringbolts with Dyneema strings, but the net itself is not Dyneema.
Ove also seen round sailbattens threaded through a net and U-bolts. That way, the load of a Dyneema net should be distributed more evenly on the attachment points. One needs a central lashing in this case to pull it really tight.

Maybe folks can share pictures of how their nets are attached?
I'll post a picture of ours later.

[Franziska]

Our attachment.
Within the aluminum beam, it's just thick knots.

[skipperpete]

Originally Posted by Franziska

Our attachment.
Within the aluminum beam, it's just thick knots.Attachment 280672

Here’s the bungee and sail slide setup.The existing net is great to walk on but its starting to age from the tropical sun. Still good but needs re stitching.

[Franziska]

Mistaken post.

[Franziska]

Originally Posted by skipperpete

Here’s the bungee and sail slide setup.The existing net is great to walk on but its starting to age from the tropical sun. Still good but needs re stitching.

That's interesting. How long does the bungee last? Is it a special one? I take it you are not stretching it a lot during install, just enough to give a little tension?

[HeywoodJ]

Here are our Ultra Cross nets (we find the knotless netting very comfortable on the feet, or when lounging). On the aft and inside edges the nets have a bolt rope that is in track, this means there is no gap when stepping onto the nets from the most frequent direction. On the other two edges there is a batten in a pocket on the nets, and this is lashed to the boat with Dyneema lashings. The lashings are a compromise, not one every hole, but not all one. With the batten and the way things are fixed, if one lashing comes completely away the hole is still too small to fall though.

[skipperpete]

Originally Posted by Franziska

That's interesting. How long does the bungee last? Is it a special one? I take it you are not stretching it a lot during install, just enough to give a little tension?

The current bungee is 5 years old on one side and 6 on the other, the casing is still fairly good, its the rubber core that’s not doing as well as it should be. This is preventive maintenance, not a failure BUT some of the slides have broken in places where it will be necessary to un thread the whole net so thats why she gets new bungees.

[fxykty]

We put a 10mm line along the edge with 3-4 rows of extra net bundles to it as our edge rope. Each attachment is VB cord x4 or x5 loops, tightened with a ratchet so that the net is super tight. It deflects less than a couple of cm when standing on it - that’s all in net stretch, not the attachments.

Black is very cool at night - it’s like there’s nothing there! Took a while to get used to stepping onto it.



Forward corner:


Aft corner:

[meirriba]

This is during installation.
I have went around tensioning the lines 3 times.
There are 2 continous lines. one on the front crossbar and one at the back of the trampoline (near the saloon).
On the deck sides, I have used short pieces of cord, each deck eye has its own.
much easier to tension when you go around, and if a line chafes, you replace only this piece. No need to replace the whole line.
I have also a tool made for the continous line tensioning.

[team karst]

My foot, or small dog, wont easily go thru these spaces.