Speed indicators and sail trim :)

Status
Not open for further replies.
Dec 20, 2010
294
Yankee Condore 21 Halifax
HIee,

I just recently installed Linux Mint v12 and have also upgraded OpenCPN to version 3. It would not run under the older version of Mint. I kept getting segmentation faults. Anyhow the new version has something called dashboard wherein you can connect various instruments to opencpn and have the data displayed on the dashboard plugin. I intalled the compass which shows a compass heading as well as a numeric display of the heading AND SOG at the bottom of the display. Very kewl :dance::D stuff. Anyhow yesterday while out sailing I learned something. In trying to sail as close to the wind as possible to make maximum distance toward destination, I use to keep the main sheeted in pretty tightly. By seeing my speed I learned that by actually letting it out a bit more I actually was moving faster:D. I thought that it would have been spilling the wind but NOT the case YEAH.

c_witch

PS in 8 knot winds I as making about 2.5 to 3 knots on either tack under main alone. I don't know it that is good or not but seems ok.
 
Jul 24, 2006
628
Legnos, Starwind, Regal Mystic 30 cutter, 22 trailer sailor, bow rider NEW PORT RICHEY, FL
I just installed Linux Puppy

I installed linux puppy to an old desktop that wasn't working and now have an internet machine, sans windows.
I chose puppy because my Ram is only 512. What machine are you running your Mint 12 on? Lots of Ram? I wonder if puppy can handle openCpnet and charts?
I think you are making great speed to windward with only the main up. But, why didn't you hoist a jib? I would think a jib-any jib would greatly improve your speed. I would be very happy if I got 3-4 k from 8k wind to windward! Keep sailing, friend! Pat
 

Joe

.
Jun 1, 2004
8,200
Catalina 27 Mission Bay, San Diego
Actually, you can get all that info with a simple handheld gps. If you know where you're going.... put in a waypoint, then activate the navigation feature on the gps.... tons of extra data will show up.... use the vmg (velocity made good) feature to tell you what progress, in speed terms, you're making towards your destination. What you may find is that sailing closehauled at 3 kts may not be getting you to the mark faster than bearing off a bit to increase speed. The vmg will tell you which is the best angle.

BTW...... putting up the headsail will make the boat perform a lot better... it complements the mainsail and improves pointing considerably.

If you don't have them already, install tell tales on your sails.... single tells on the mainsail leech, pairs on the headsail luff. instructions are in the packet when you buy them.... they're inexpensive and return a huge benefit.
 
Dec 20, 2010
294
Yankee Condore 21 Halifax
We do have a handheld unit but I'd rather not have to contend with it. I find it easier to look in the cabin at the laptop display and that will be much improved once I make a pedestal for it to sit on. The reason I've not been using the jib is 1) I wanted to get a good feel for the boat and how it handled under the main alone. 2) The line coming into the drum is at a very bad angle and when unfurling it tends to jump up off the top of the drum and foul around the sail. I am still thinking of ways to over come this but nothing firm has come to mind as yet. Sailing with the jib might have added a 1/4 to 1/2 knot.

c_witch
 
Feb 26, 2004
23,050
Catalina 34 224 Maple Bay, BC, Canada
Doesn't matter where you look for your information, but VMG would be at the top of my list, Joe's right.

For your furler, find "THE" spot where the furling line comes directly straight off the drum and find a fairlead that will work. Some folks put them on their pulpit, others on deck. Johnson makes a good batch of bullet fairleads with various configurations.
 

Joe

.
Jun 1, 2004
8,200
Catalina 27 Mission Bay, San Diego
We do have a handheld unit but I'd rather not have to contend with it. I find it easier to look in the cabin at the laptop display and that will be much improved once I make a pedestal for it to sit on. The reason I've not been using the jib is 1) I wanted to get a good feel for the boat and how it handled under the main alone. 2) The line coming into the drum is at a very bad angle and when unfurling it tends to jump up off the top of the drum and foul around the sail. I am still thinking of ways to over come this but nothing firm has come to mind as yet. Sailing with the jib might have added a 1/4 to 1/2 knot.

c_witch
Get the furling line re aligned. I have never sailed my boat with main only... you won't learn anything about your boat sailing that way. The main just works better with the headsail.... as far as your increased speed estimate... what do you base that on if you're not putting up the jib. I will tell you that when motoring, drop the jib and proceed with a reefed main only.... the sail will help keep the boat stable under power.

The laptop works fine in the cabin..... but I'll bet you a dollar you won't even be able to see the display when you get it out in the sunshine!!!! I tried mine outside and it was a total failure. At night, for sure, but bright daylight.... nope. So..... leave the laptop in the cabin for route planning, etc. A handheld Garmin 72 or 76 with with mono display is way easier to see and very easy to operate with just a little thumb movement

The color displays on the more expensive handhelds and fixed mount gps/chartplotters are fantastic..... but a simple laptop screen will not be the same.
 
Jan 24, 2005
4,881
Oday 222 Dighton, Ma.
Joe,
I have to respectfully disagree with you on that. Sailing with just the Mainsail is great practice for picking up your mooring under sail or sailing up to a dock. I do this all the time at our club. Some sloops just don't maneuver well under Mainsail alone. Fortunately my O'Day 222 does. Also, I do a lot of trolling for Striped Bass and Blue fish under sail and it's a lot easier to play a "fish on" with just one sail to contend with. Two sails would would add too much speed for trolling.
When I want to get to my destination fast though, I put my rod down and roll out my Gennie. I agree with you that two sails are better than one but you can learn a lot about the maneuverability of your boat by practicing these two things that I just pointed out when you use just the Mainsail.
One day I tried to come up to the dock with just my Gennie and it was almost a total disaster. The Mainsail has never let me down though.

Many times I have practiced sailing my boat downwind under bare pole in a strong wind. Now it may seem foolish to practice something like this, but this past spring it really paid off.
I launched my boat at the club ramp on a day that I wouldn't normally launch which I admit was "my bad." Due to unforeseen circumstances and the state of the tide, I didn't have time to get my mast up on dry land.
After the splash, I proceeded to motor upwind to a protected cove in hopes of getting my mast up. Then, my motor conked out and I was dead in the water about a half mile from the club in a strong wind. The mast was laying in the crutches and all I had was my rudder to steer with. So I let the centerboard down and that boat steered straight back to the club. In fact I set up my autopilot and she steered as straight as an arrow. She was on one side of the river and the club was on the other side, but I was able to maneuver the boat at a good angle perpendicular to the wind in order to get to one of our club moorings and tie her off.

I have to admit that having my outboard conk out like that was also "my bad." I usually test my motor in a barrel and put the mast up on my boat at the house every spring, and I did this, but in spite of my screw ups I made the best of a bad situation by learning these things. I learned a long time ago that it's always smart to have an alternative plan to fall back on just in case the original plan fails.
 

Joe

.
Jun 1, 2004
8,200
Catalina 27 Mission Bay, San Diego
Joe,
I have to respectfully disagree with you on that.........etc...
You're absolutely right, Trinkka..... I was being a bit dramatic, to make a point that his boat will perform much better with both sails to encourage him to fix the roller furler.......... I do maneuver around the slip with main only.... but it's hard to tack my boat, especially in light air, without help from the jib.

Now that I look at it, I could have presented my case a little differently.... so thanks for your comments. Now I don't have to rewrite it....heh heh.
 
Jan 24, 2005
4,881
Oday 222 Dighton, Ma.
I also encourage C_Witch to get the roller furler control line angled correctly so that it can work whenever the Gennie is needed. The last thing you need is a stuck furler control line with a riding turn on the drum when you want to furl the Gennie.
 
Mar 2, 2011
489
Compac 14 Charleston, SC
The furling line must be at a 90 degree angle from the drum or the line will spill off one end as you've described. Use any square object to eyeball the angle, it doesn't half to be perfect but you'll see how it helps right away.
 
Status
Not open for further replies.