Nacra Bridle Foil help

it is definitely not a solid extrusion as the end caps fit inside of it in the same fashion the end caps fit on your nacra beams.

if i find a reason to head over to my brother's house i'll take some pictures of mine.

Edited by matt922 on Aug 13, 2013 - 12:07 PM.

Zach,
I can get you some pics. The kingpost (striker) on the foil is stainless female threaded rod, with a male SS treaded rod to adjust prebend. The V shape SS rod is attached over the kingpost and terminates at the end into SS tangs. The factory foil is an asymmetrical extrusion, but the complete design is very robust and can accommodate tremendous loads. For starters, look in my album and you can see several pictures. If you need more I can email you some high resolution pics directly.
http://thebeachcats.com/pictures/?g2_itemId=18279
Here are some pics you might find helpful

P.M.

Those are great pictures and information. I do have a couple requests.

1) What is the length of the foil for a 5.8?
2) Can you get a good close up picture of the foil ends and also a close up of the kingpost(striker)?

Hopefully I don't end up hijacking this thread but at the risk of asking a dumb question, could someone elaborate what the bridle foil's function is, how and why? I've heard that they increase pointing ability but I don't know how and it if is just the foil itself or adjustments that you make to it while sailing....

Also, found on a site trying to find more info that the foils are 70" long
http://www.catsailor.com/forums/ubbthreads.php?ubb=showflat&Number=176521)

Thanks

Steve (on this forum) has the Original P19 MX and the difference in sail size & horse power from the regular P19 is impressive.

I am sure P.M. (or others) can fill in all the details of imploding cats in the 80's but i think Prindles were failing with the addition of bigger jibs and mains and needed to add strength in this part of the rigg.

adding a foil (often a mast section) or beam to the front of a catamaran will disperse the load that is pulling your bows inward

and by adding it it will also stiffen up the bows - reducing flex twist of the front beam (and hulls) which will reduce it in the middle and rear beam and recapture all the speed & pointing loss associated with flex.

Edited by MN3 on Aug 16, 2013 - 10:07 AM.

The foil pulls up on the hull more than in. On your 5.2, if you went up your bridle wires from the hull 6 inches, chopped the off, put on a foil, you could:
1) keep the angle of the stress on the hull same
2) have a lower tack point for the jib, keeps the power low in the sail
3) have more room so you can add a larger jib.

The foil itself has nothing to do with pointing or speed.

The Nacra 5.5 SL and 6.0 NA were designed with the foil, the 5.8 adopted the foil and added a larger jib and became the 5.8 NA

hc16runner wrote: Those are great pictures and information. I do have a couple requests.

1) What is the length of the foil for a 5.8?
2) Can you get a good close up picture of the foil ends and also a close up of the kingpost(striker)?

I'll see if I can get some pics this weekend and measurement.

All makes sense thanks guys, maybe I'll do that some day. Saw a 5.2 and a 5.5 earlier this week with them on and started wondering, once I saw this post I had to ask.

x

Edited by MN3 on Aug 16, 2013 - 02:18 PM.

I'll be happy to post pics of the progress/results when I get a chance. Just getting the parts I need first before I start fabricating it. 70" was what I guessed for the bridle foil length based on the measurements I took from my boat.

Hey Zach any progress on the foil, I want to fab one myself for my 5.8

The supercat design may be easier to manufacture at home.

http://thebeachcats.com/pictures/?g2_itemId=106194

This was done using the H16 side bar, kingpost and rods. The rest we fabricated ourselves. I agree with carolinacatamarans - it would probably be easier to do the supercat design at home.

Zac your foil looks plenty strong, I will search for a photo of the supercat design
cheers
carl