Thank you for taking the time to read this. It’s good to know the community is still active!
I’m relatively new to sailing catamarans, and the SC15 is my first cat. I’ve raced about half a dozen times now, and I’m getting frustrated trying to figure out why the other cats seem to point higher and sail faster than I do.
My current setup:
* Supercat 15
* Square-top Sabre mainsail
* Roller-furling jib
* Asymmetrical spinnaker
Here are the things I’ve noticed:
1. Mast rotation
My mast rotates almost 90 degrees even with the traveler centered. Could this be excessive, and could it be affecting my pointing ability or the airflow across the sails?
2. The boat feels heavier
This might sound subjective, but my boat feels noticeably heavier than the other cats when pushing it around on the beach. I know they’re all supposed to weigh around 300 pounds, but the difference is noticeable. My hulls are dry, so I don’t think I have a water intrusion issue.
3. Mast rake
My mast rake is minimal. I’m assuming it’s close to the factory setting of around 5 degrees, but I haven’t verified that measurement.
4. Pointing ability and jib performance
When I try to point higher, the jib is the first sail to start luffing. I bear away slightly to build speed, which works, but then I’m sailing 5–10 degrees lower than the Hobie 16s, and they’re still going faster.
I’m wondering whether my roller-furling jib is the correct size and cut for my square-top main. Could the lack of battens in the jib be hurting its ability to maintain its shape and point higher?
I’m also wondering whether excessive mast rotation could be contributing to the problem, although I’m not sure whether that’s a realistic concern.
5. Boat trim and leeway
I understand the importance of getting the bows down, and I have no problem burying them once I get enough speed to trap out and move forward of the front beam. My wake doesn’t appear to indicate significant sideslip, although I realize that’s not a definitive measure of leeway.
I’ll attach a photo for reference. This was taken after building some speed and attempting to point higher. I realize the jib halyard tension isn’t correct in the photo because I had an equipment failure during the race. However, I was experiencing the same pointing issues before that failure.
At the time, I was trying to sheet in and head up, but my windward mainsail telltales were streaming forward. The jib would then begin to stall, forcing me to bear away to regain speed.
I’d appreciate any thoughts from those familiar with the SC15, particularly anyone who has raced against Hobie 16s.
Am I looking at a sail-shape or jib-size issue, mast rotation, mast rake, or something else entirely? Are there specific setup measurements or tuning adjustments you would recommend checking first?
I’m happy to hear criticism of my technique, too. I’m trying to identify the actual problem rather than simply assume the boat or sails are at fault.
Thanks in advance for any advice!
SC15 pointing
SC15 pointing
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Matt Haberman
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Re: SC15 pointing
Hello,
Here are my thoughts on your questions:
1) Mast Rotation & Mast Rake - the proven setup was to first establish the desired mast rake, typically 5 degrees relative to the deck (in directly in front of the beam). You can use a roofers protractor, or there are quite a few smartphone apps available you can try. Once the mast rake is established the side stays were adjusted so that the mast could be rotated by hand (without sails) so the track pointed towards the end forward beam.
2) Boat weight - Yes the published weight of the 15 was 300lbs, but keep in mind that was when the boat was new. As they age they tend to gain some weight from moisture and modifications. I believe the 300lbs was for the unirig, so add the weight of the jib and associated hardware along with your spinnaker rig and I would bet that you are at least 325lbs. Only way you are really going to know is if you weigh the boat with all your gear. This can be done pretty easily on solid ground with a bathroom scale and weigh all 4 corners individually.
3) Boat trim - the bow needs to be down going upwind. The waterline needs to be underwater at the bow; the tip of the bow should be only an inch or two out of the water going upwind. When going upwind the skipper should be forward, in light winds they should be in front of the sidestay, in moderate winds they should still be forward, typically right at/behind the sidestay on the windward side. The crew should always be in front of the sidestay when going up wind. In light wind they should be on the leeward side and as far forward as possible. Often times the crew would sit on the forward beam/hull intersection with they legs on the tramp and their hand on the hull in front of the beam. The crew has a big influence on how far down that leeward hull is driven.
4) Sail Trim - It is really hard to tell from the photos, but it looks to me in the photo with the H16 that the mainsail really needs to be trimmed in. Don't worry too much about the flow of the windward telltales, it is the leeward telltales that are doing all the work. Make sure the leeward ones are flowing and if you can get the windward ones to flow great, but don't sacrifice good flow on the leeward ones. The jib is typically sheeted in pretty hard going up wind, but if you over do it, it will disrupt the flow on the leeward telltales. Going upwind the luff of the jib is your indicator of how high you can go, typically you would sail right on the verge of the luff starting to soften. How much Jib downhaul you have can also influence this.
I cannot say that I recall personally racing the 15 against H16's but looking at different handicap rating systems, it appears that the two boats have similar performance numbers. Looking at the handicap numbers and from what I know of the boats I would expect upwind performance would be similar depending on conditions, however downwind I would have to believe that there would be no contest. With the hull volume on the SC15 you should be able to push the boat a lot harder then the H16 can be pushed. So around the course it might be a game of making your gains downwind and holding your position upwind...
Here are my thoughts on your questions:
1) Mast Rotation & Mast Rake - the proven setup was to first establish the desired mast rake, typically 5 degrees relative to the deck (in directly in front of the beam). You can use a roofers protractor, or there are quite a few smartphone apps available you can try. Once the mast rake is established the side stays were adjusted so that the mast could be rotated by hand (without sails) so the track pointed towards the end forward beam.
2) Boat weight - Yes the published weight of the 15 was 300lbs, but keep in mind that was when the boat was new. As they age they tend to gain some weight from moisture and modifications. I believe the 300lbs was for the unirig, so add the weight of the jib and associated hardware along with your spinnaker rig and I would bet that you are at least 325lbs. Only way you are really going to know is if you weigh the boat with all your gear. This can be done pretty easily on solid ground with a bathroom scale and weigh all 4 corners individually.
3) Boat trim - the bow needs to be down going upwind. The waterline needs to be underwater at the bow; the tip of the bow should be only an inch or two out of the water going upwind. When going upwind the skipper should be forward, in light winds they should be in front of the sidestay, in moderate winds they should still be forward, typically right at/behind the sidestay on the windward side. The crew should always be in front of the sidestay when going up wind. In light wind they should be on the leeward side and as far forward as possible. Often times the crew would sit on the forward beam/hull intersection with they legs on the tramp and their hand on the hull in front of the beam. The crew has a big influence on how far down that leeward hull is driven.
4) Sail Trim - It is really hard to tell from the photos, but it looks to me in the photo with the H16 that the mainsail really needs to be trimmed in. Don't worry too much about the flow of the windward telltales, it is the leeward telltales that are doing all the work. Make sure the leeward ones are flowing and if you can get the windward ones to flow great, but don't sacrifice good flow on the leeward ones. The jib is typically sheeted in pretty hard going up wind, but if you over do it, it will disrupt the flow on the leeward telltales. Going upwind the luff of the jib is your indicator of how high you can go, typically you would sail right on the verge of the luff starting to soften. How much Jib downhaul you have can also influence this.
I cannot say that I recall personally racing the 15 against H16's but looking at different handicap rating systems, it appears that the two boats have similar performance numbers. Looking at the handicap numbers and from what I know of the boats I would expect upwind performance would be similar depending on conditions, however downwind I would have to believe that there would be no contest. With the hull volume on the SC15 you should be able to push the boat a lot harder then the H16 can be pushed. So around the course it might be a game of making your gains downwind and holding your position upwind...