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Getting my maricat to point higher?


BarryK1200LT

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I raced my Maricat on the weekend. I've only competed on 2162 in one other race event, and that was the time I broke the mast on the second lap of race one.

So until last Sunday I'd never had the opportunity to see how 2162 would sail against other similar sized cats and other Maricats.

I found on Sunday that I couldn't get 2162 to point anywhere near as high as the other 14 footers, or maintain boat speed unless I bared away further from the wind.

At a guess, I'd say that I had to run at least 10 degrees further off the wind to maintain boat speed, and that meant that by the time we reached the windward mark I was a couple of kilometres behind the second last boat.

The only point where I seemed to be able to holld my own was on the reaches. But sailing up wind I just couldn't point anywhere near as high as the other boats (including another Maricat).

So what are the key points to look for that might help me to point higher than I'm able to now?

Any advice will be appreciated.

Cheers

Barry

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Don't know Brad, but I hope to find out because it was very frustrating on Sunday seeing all the other boats point way higher than I could.

While it was frustrating, its still good in the sense I got to see how my boat compared to others.

When I go out for a fun sail on your own, I'd never really took notice of my boats pointing ability, because I'd generally just spend the day sailing off the wind at whatever angle produced the most boat speed, and then just enjoy the ride.

It's not until I went head to head with other boats that I begin to realise my pointing ability sucked big time.

Cheers

Barry

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Hi Guys,

Mast rake is definitely a key factor in a board-less boat... You're effectively moving the "centre-of-effort" in the sail closer to the point of "lateral resistance". In a boardless boat (to keep it simple) this is basically the rudders.

On the Mari's that is basically dictated by "block-bounce"... this is when sheeted to (optimum=hard) windward in about 15kn the mainsheet blocks are touching (or bound up if you will- these are low profile blocks as well)... That's the way we used to do it.... Mick and a couple of others probably have a more definitive way of checking/measuring this.

The 4.5 seeeems to be pretty much the same. I've been going higher and higher on the forestay (now second hole from the top) with firm rig tension and it seeeeems to be getting quicker, higher and more manageable.

Probably need to do some more racing to comfirm. It's also helping to keep the bows up with the kite on so it's all good.

Hope this helps,

Regards,

Leroy wink.gif

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Might conflict with other suggestions but I found in light conditions to get your weight forward and on the tramp, not on the windward hull.

Object was to get the leeward hull lower in the water and as much of it in the water as possible. I used to transfer my weight to the point where a sliver of water would run up and over bow curve and up the sloping bit of the leeward hull that the front beam connects to. If you sit too far back (in light conditions say 1-6kts) there is reduced lateral resistance because the hull is more rounded at its centre to rear than at the front causing the boat to side slip more.

The more the wind picks up then by default more of the leeward hull is in the water. If you find that at about 10kts breeze you still cannot point as high then there are other factors such as mast rake, rudder drag, etc.

I sail with a neighbour on a new nacra 4.5 and he cannot point as high as me in my sail blown mari 4.3. A beautifully engineered boat though. Pity the same manufacturer cannot implement the same rudder mechanism for the mari. Cannot be too hard. The double rope system on mine is a load of s.... Gotta spend this week on rudder repair because of a rope jamming. Might be OK for Lake Macquarie and Port Stephen ponds but totally unsuitable for off the beach sailing. The old hyfield lever was better.

It makes me think the the lighter foam boats may not have the pointing ability of a heavier GRP boat in light conditions. Having never seen one this is a guess. The nacra 4.5 is foam and rides very high in the water. Bloody hard to get back up on after a capsize. But easy to right.

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There is plenty of info on mast rack in other threads or on the website. As Lachy says it should be just in front of the back beam but it depends on the sail cut. Are your telltales on both sides of the sail streaming ? How far out is your traveller ? How flat is your sail ? How much down haul do you use ? Is your leech straight ? Lots of things to try.

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Thanks for the suggestions so far. There is clearly a number of things to take a closer look at with my tuning.

I'll work at making one adjustment at a time starting with mast rake which I'm guessing will require shorter rear shouds and longer front ones, then see how that effects my boats ability to point higher upwind.

I noted that the sail may need to be recut to compensate for the extra rake in the mast? Is this just a trim of the foot of the sail to reposition the boom, or is it a major recut and rework of the whole sail?

Reason I ask is that if the later applies, then a new sail may be the more cost effective way to go in the long run?

Cheers

Barry

[This message has been edited by BarryK1200LT (edited 21 January 2008).]

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One question that should be asked is are you sailing sloop or cat, cat generally will point higher than sloop. Your post also highlights one other thing, you can fun sail all you like and have a ball, but until you go up against other boats you really have no idea of how you or the boat are sailing. Another thing to try for more pointing ability is to increase the amount of mast rotation by grinding some out of the stops on the mast step, Pedro normally says to grind the stops back so they are at 90deg to the axis of the boat, or so that the mast when rotated has the sail track is pointing at the side stay.

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I have an 'old' sail and don't have my mast raked quite as far as the hot boats (I don't go as quick either but until I can tack properly and stop capsizing then that'll continue!). I havn't had to change the sail at all. If I want to rake a bit further I understand that I can just get another hole put into the clew a couple of inches higher up (still in the reinforced area).

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Originally posted by korwich:

One question that should be asked is are you sailing sloop or cat, cat generally will point higher than sloop. Your post also highlights one other thing, you can fun sail all you like and have a ball, but until you go up against other boats you really have no idea of how you or the boat are sailing. Another thing to try for more pointing ability is to increase the amount of mast rotation by grinding some out of the stops on the mast step, Pedro normally says to grind the stops back so they are at 90deg to the axis of the boat, or so that the mast when rotated has the sail track is pointing at the side stay.

Hi Korwich,

I generally sail sloop rigged, but sail cat rigged when the winds at around 15 knots + ?

I'm looking forward to going out next time to try out these changes.

Cheers

Barry

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If you are sailing sloop rigged, check you are not sheeting the jib out too wide. It should be about a 30 to 40 mm off the mast but not backwinding the main. I thought that if you wanted to point high upwind bring the mast back to near vertical. To reduce the risk of pitchpoling on a reach you raked the mast back. It was a compromise. lose pointing ability on the windward leg by raking the mast, but gaining in speed/handling on the reach.

my 2c

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This could sound a bit esoteric but a cuppla more things to consider.

One is the assymetric design of the hulls which can affect pointing and boat speed or both at the same time. Dunno about the new boats because they float higher but in the old days I used to try not to sail flat (if wind permitted).

I found that the optimum was to have the widward hull just kissing the water. This seemed to be the angle by which the leeward hull reduced its cant angle and became vertical. It also minimised the wetted area of the hull.

Whilst flying a hull may look cool it will slow the boat down and degrades pointing ability beecause of side slip, decrease in horizontal sail drive (force is pushing leeward hull into the water and not across it), and wind getting under the tramp.

If in really light conditions you can't maintain boat speed (which makes you think it is not pointing as high) then check the alignment of the hulls. The manufacture (or others smarter than me) can tell you how to do this.

Off memory measure starboard bow to port stern and then visa versa. The measurement should be the same. If not loosen the beam bolts and adjust. Place boat on flat smooth surface to do this. A small adjustment can make a large change....

[This message has been edited by Spectre (edited 23 January 2008).]

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  • 2 weeks later...

First thing to check is batten shape, most older boats will have the battens shaped so that the drive is about 30-35% from luff. This will cause the symptoms described, current sails have the drive 40%+, aft, giving much better pointing abillity. Mari cat rig stays are currently 5.5m (forestays) and 5m (sidestays) and raking the mast WILL improve pointing. Have another clue added to your sail 6-8" up from the original. Ph 0243591729 Darcy

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  • 3 weeks later...

Just a follow up to all the great advice that was kindly offered on this thread. Last week I got around to having my rear shrouds shortened enough to allow for more mast rake adjustment, and on Sunday I took 2162 out for a sail from Raby Bay to see how things would go.

When setting up I set the mast rake so that the top of my mast was about 600mm in front of the rear beam. This meant I was left with only just enough room for the main block to pull sufficient tension on the main before the blocks would touch. (I'll be getting the sail foot trimed and a new clew eyelet put in this week).

I spent the first few hours relaxing on the tramp contemplating the joys of sailing on such a fine sunny Qld day without any wind, and concluded that bobbing around on a catamaran going no where was still a damn fine way to spend a few hours.

Eventually the breeze began to build to a steady 10/12 knots. The difference in the way 2162 performed was immediately obvious, with far less tendancy to be nosey either beating up wind or when on a reach.

WHile i think the pointing ability was improved, I won't really know that until I get a chance to go head to head with other boats.

The only boats I had to compare against on Sunday were a Hobie 14 turbo, and a Hobie Getaway and I managed to make good gains to first catch, then pull away from both.

So overall I'm very happy with the results, and my thanks to everyone who chipped in with advice.

Cheers

Barry

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Originally posted by Loose Change:

G'day Barry

And have you noticed any change in your tacking ability after raking the mast back? When I rake the mast back on the 4.8 it does not want to come through the eye, absolute bitch of a thing.

Harry

Hi Harry,

Not really. I was sloop rigged on Sunday, and the jib made tacking easy. Might be a totally different story cat rigged.

Cheers

Barry

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Hi Barry

Good to hear of the improvement in pointing, you really need to sail against another Mari to check how much of an improvement you have effected. I finally got around to cutting back the mast rotation stops on my boat the other weekend, (to allow more mast rotation) sailed in the marathon at tanilba on sundaya week ago, beat micks new boat and every other foamy out there, on an old maricat with a monohull jib and a second hand mainsail. (sorry pickle) The boat pointed better, ie it was able to keep up with the cat riggeds and it flew, thats the only thing I can say that I did different to usual to win (OK so mick was'nt sailing his boat but it was being sailed by another experienced sailor). Maybe I concentrated better I dont know. FWIW My mast is I think now raked further back than 5050 but we both sail super sloop, so I don't really experience tacking problems with my boat. (I guess that I'd better go back to the tail end of the fleet now where I belong.)

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Hi Korwich,

I looked at that too, and can see that more mast rotation would help the air flow over the luff of the sail better. But I also thought perhaps modifiying the mast base to allow more roatation would mean your boat would no longer be class legal?

If it doesn't effect class spec's, can I ask how you went about cutting the mast step to allow the mast to rotate more?

Cheers

Barry

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Hi Barry

The main thing with rotation is as I understand it is it allows more bend in the mast, in the right direction. All we do is using an angle grinder, take away the wings on the side of the mast step so the rotation stops align athwartships across the boat (ie at right angles to the longitudinal centreline of the cat), be careful where you aim the stream of sparks Aluminium creates a spark many times hotter than steel, avoid the car, avoid your tramp, avoid the house windows, etc. If you were to be correct with OHS you should use a sanding disc in the grinder rather than a grinding disc as Al can cause the disc to become "loaded" with Al which has been known to cause discs to explode, but everyone just uses a grinding disc just the same. You may end up cutting into the void under the mast step this is not a problem and doesn't affect the stength of the mast step. After work with the angle grinder you can dress up your work with either a die grinder with a steel burr or you can use a wood chisel to pare and chamfer your work to make it look nice. Altering the rotation is still class legal, you are just not allowed to have the amount of rotation ajustable on the water.

If I could figure out how to post photos into this forum I could post a picky of my mast step.

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