hi all,
very new cat sailor here with more time to read at home than sail:o(
and looking at a winter where for at least 4 months it will be too cold to sail, (ice on the lake!)

so far i've found the free download hobie guides very good for explaining basic sailing and cat sailing concepts to a newbie

here on lake nojiri, in the mountains of japan, there are only maybe 3 cats. my nacra 5.2 and two hobie 16's owned by very mellow guys, (the one i know has a trapeze but has never used it)
so i doubt i'll ever be racing my cat against anything of similar performance,

but i'd still like to know how to use all the adjustments to tune my boat for best speeds

wing mast, diamond wires, mast rake, downhaul, outhaul etc

so which hobie tuning guides would make the most sense to study and experiment with on my rig; the 16, 17, or 18

eric e

i've found the australian race tuning guide for the 5.2, most of which i'm still struggling to understand, presume that toeing out the hulls isn't something that i need to bother with....

the 18 won't be far off, but I feel sure that someone will come up with a 5.2 tuning guide for you. what are you struggling with on the Oz site?

The 18 is the closest thing to the 5.2 but every type of cats is different. I wouldn't look at that to much.

I would stick to the Australian guide for the 5.2 and just ask people on here about the things that you don't understand.

Mast rotation is very important and you can use it to flatten the sail or power it up. The diamond wires on the 5.2 are not as advance as those on some of the newer boats. No prebend on the 5.2. Mine are set so that about 5 inchs from the bottom attachment point it is hard to press them to the mast. I am not sure if that is the best setting but I know my boat keeps up with others well.

The mast rake on the 5.2 is not a big deal. I run mine with very little rake. Maybe 8-10 inchs off straigh up at the tip of the mast.

Downhaul on the 5.2 unless you have upgraded the system isn't something you can work. I set mine when I head out to the condition and adjust it if things change but I don't play the downhaul because I haven't upgraded to a system allowing that. Get the wrinkles out and then on big wind days crank down on it.

Outhaul, I have two rules for the outhaul, upwind all the way out on a sloop rigged boat. and then let it off downwind.

Alot of this comes from Rick Whites "Catamaran Racing for the 90's" There is also an 80's version that I am trying to find because it has a specific 5.2 tuning guide

Hey erice, What part of Japan are in? I spent a month in Iwate Prefecture staying with families in Ofunato, Miyako, Hiraizumi, Morioka City and other places. The people were wonderful and the cities beautiful. I would love to go back someday.

Hope you enjoy your cat. I recently purchased an H16 and am still confused about some of the techniques and rigging procedures. This site is a great resource for info. Lots of helpful folks willing to answer your Qs. The technical jargon is what really gets me. I have yet to learn all the pieces and parts. <img src="http://www.catsailor.com/forums/images/graemlins/grin.gif" alt="" />

hi wallybear, we live in nagano city, where the winter olympics were in 1998

about 35 minutes away we have an old holiday house on lake nojiri, which is where the nacra is. pic attached to 1st post

eric e

hi all,
gree thanks for your 5.2 advice, esp about the the early 80's nacra downhaul system needing to be upgraded for modern useage, (couldn't imagine letting go of tiller and leaving sheets cleated during big gusts while i used 2 hands on that weak pull down system every time i needed to de-power)

TEAMVMG, i keep rereading the 5.2 tuning guide at

www.goosemarine.com.au

and understanding it more but these bits i would still appreciate input about

1. Hull Alignment.........35mm toe out.

on short track auto-cross for cars, toe out is used to help initiate turns at the expense of straight line stability
what's the purpose of toe-out for cat hulls???

3. Dagger Boards.........Parallel to centre line of hulls.

like you have a choice???

4. Mast settings........... Spreader Rake: 5 mm behind mast track.

ok easy, my 5.2 has the older spreaders that have no rake and are not adjustable

5. Diamond wire tension.............Tight
Tighten just enough so as not to induce any prebend.
This will allow Cunningham to work to its full extreme to
induce bend as required.

does this mean the mast becomes sort of like a batten and must pop across during tacks and jibes???

6. Mast Rake...................Centre to rear off hatch.

translates as, mast straight up, (at 90 degrees to tramp) or angled rearward slightly so that top of mast appears inline with the forward inspection hatches on the hulls when viewed from the side???

7. Boat Trim.…………...When sailing to windward and reaching in flat water have leeward Bow driving in to about 50mm before
deck.

whole downwind hull is underwater until 50mm before main beam!!!?

sorry for the long list of Q's but as it was written as a race tuning guide for experienced cat sailors newbies like me can get a bit lost...like all these references to "wild thing"

eric e

The toe out thing... I am not sure about.

You really don't have much choice with the daggers, just make sure they fit tight in the slots.

Mine has the old spreaders too, so no worries there.

I don't think I want my mast doing much popping, but it should be bent backward a little when you crank the downhaul. This is one area I am not really very knowledgeable right now. But will be working on soon. I have been thinking about the new spreader bars.

The mast rake can depend alot, I adjust, less in light wind and more in heavy wind but I am talking 1 inch adjustments

About the boat trim, I don't think you want to be quite that far under. It means from the top corner of the bow or where the deck starts. That is still scary at times but you can actually drive the bows under to the front crossbar and if you stay near the back of the boat she will come down upright. I have had 4 inchs of water over the crossbar and still stayed upright.
The trim is much more important in light wind and upwind sailing.

I am rigging my new downhaul tonight, I am going to upgrade to 8:1 or at least that I what am planning, time to start working on it. I can send some pictures if you want.

pics, yes please, pm sent

Well, it is all assembled in the living room, now just to attach it to the mast. But that will have to wait for daylight.

The toe out that they talk about is not of a major concern, it was used to get the most out of the cats when there was very competitive racing in the class way back. It is there so that "theoretically" the hulls will be pulled into parrallel aligment when the rig tension is applied as that static and sailing rigging load will always pull the bows slightly towards each other.