Wednesday, August 27, 2014

Race: Hospice regatta

This was a two day event in Oceanside with five other boats in our class. Day one was three WL races and day two a random leg race.

I went in with some expectation to be mid fleet but the first day we were missing a person in pit and a new person on board and the other boats ahead of us were all on form. Our results were 5/6, 5/6, 3/6.

The next day we went in with an extra person so had pit properly covered. Our sailing was a lot better but it was difficult to tell how we were were doing as one of the slowest boats in our class. When we got the results we were once again 5/6. Damn... especially when the silver lining though is we were 49 seconds off first place on corrected time after an hour and a half on the water.

Looking at the track we lost this race on two decisions. Firstly at the leeward mark where we wiggled deep to drop the chute and lost position to a boat in a different class, taking a slow wide rounding. Secondly I didn't commit properly to the wind going left, and sailed up the right of the course not the left. The wind then shifted left. We should have been on the left of the course.

Our starts were solid, winning two and being close on the others. Our tacks great and boat-speed felt pretty good. We're in the fight now.

Technique: This week we practiced a "stretch and blow". This involves setting your upwind sails, sheeting them in, pulling the spinnaker across the leeward side of the boat and blowing the halyard. Advantage is that you can smoothly transition to the upwind leg from a reach.

I was bow for our practice and while it wasn't quite windy enough (the wind is meant to cushion the sail above the water) and the spinnaker did get soaking it also came into the boat super easily.

That would get us halfway up the board on the RLC, then playing the shift correctly probably would have placed us near the top..... next time! Err, next time there will be something else.

Edit: Video of dolphins during the practice sail!


Gear: Wind Transducer Woes (Update)

Couple of days later I was back at the boat during the morning calm and saddened to see other boats wind paddlewheels all start spinning before Kraken's, though it did eventually spin.

So I took another trip up the mast, this time with a soapy water sprayer. Lot's of soapy water spraying and hosing off later and the instruments were reading 20 - 40% more wind.

And now it starts spinning at roughly the same time as the other boats...

As I practice climbing the mast now things are getting faster and the time for this operation was about 30 minutes of time climbing or working at the top. However coming down takes as long as going up, and it seems like gravity should lend a hand, so I'm going to start practicing self belaying, from a nice low level to begin with!

Thursday, August 7, 2014

Software: NRace polar data issue (resolved)

This might trip others up so I thought I'd post it....

I haven't had much luck getting the farr design polar data into the Nexus race software.

Eventually I realised that the farr data for some of the downwind legs has different angles in the same column and this prevents the Nexus software from being able to deal with it.

I tried the minimal massage to keep some of the data (manual interpolating to fill in a bit, and deleting one of the columns) and it can now quantify TBS correctly. Still haven't had much luck driving the steer pilot though, that's next on my list of things to try and conquer.

Software: NMEAConnection v0.9

While away I got a chance to work on NMEAConnection. New features include:
- Finds tack and gybe points
- Generates data on these points - angle tacked, leeway, loss in boat lengths
- Has a spreadsheet
- Can draw histograms of data over sections of track
- Has a snazzy map courtesy or gmap.net
- Has a dialog box to connect to the boat
- Has a text log to help operate it outside the debugger
- Remembers core settings

On the horizon is the ability to enter meta data and a transition away from the original clunky window to something a bit sleeker. I've discovered its pretty easy to integrate C++ and managed C# so I can use winforms for the windows and integrate off the shelf applications like gmap.net, a big step forwards.





Gear: Wind Transducer Woes

Heading out on Monday to finally calibrate the wind transducer and log I was presented with a still propeller and system that told me there was no wind transducer.

Sinking feeling. Even more so when I started reading into the system and found I have the more expensive Nexus nRace model that would set me back a thousand dollars to replace.

Oh well, we calibrated the log then had a nice sail double handed. Upwind and down with a sprinkling of dolphins riding the bow and cavorting in deep blue waters. At no point did the prop consider moving.

On my return I started looking into it. Part of me wondered if an electrical fault could stop the prop like that, or if an electrical strike might have damaged it.

Looking at the server two LED lights were on under the wind connections and voltages were all pretty much zero, according to the manual this indicates a connection issue.

Climbing the mast I pushed the propeller around with a boat pole (it's a bit too high for me to safely get to with my climbing setup) but it didn't want too turn. I then pulled up the hose and sprayed it with water. Just as I was about to give up and look into removing the unit from the mast top for further maintenance it started turning and a minute of spray later was running freely.

Returning to a more sensible level I turned on the instruments with some trepidation and to my relief once again have readings!

Would probably be good for garmin / Nexus to update their manual to say the LED's and a stuck propeller could just mean go clean stuff.




The two lower lights were stuck on.