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PostPosted: Mon Oct 13, 2008 8:46 pm 
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No noticeable improvement, but then mine is an Oasis being sailed solo wih one set of fins (and the leeboard)...maybe a Revolution would do better. Hoping some others with other models will try the leeboard idea and see if they can do less than 70 degrees off the wind (I'm not sure I'm even achieving 70, frankly).

Jerry

[quote="skua"]Soyjer, that sounds like an great idea! It is even simpler than I thought it could be done! I would love to see pics of your solution. Have you tried to sail with upwind, without any pedaling? If so, how did that work out?


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PostPosted: Tue Oct 14, 2008 2:13 pm 
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With the leeboard in that position I think you most probably do better then 70degrees. I also have an oasis which I often sail solo. Yesterday I tried out my alu "sock" for the drive and I was able to do about 45 degrees with it. But the drag was too much to call it a success now. I hope to be able to post more details and pictures soon.

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PostPosted: Tue Oct 14, 2008 9:27 pm 
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45 degrees?...I'm skeptical...you ARE talking about actual track and not just heading, right? Are you able to use shorelines to measure your actual progress after repeated tacks?

skua wrote:
With the leeboard in that position I think you most probably do better then 70degrees. I also have an oasis which I often sail solo. Yesterday I tried out my alu "sock" for the drive and I was able to do about 45 degrees with it. But the drag was too much to call it a success now. I hope to be able to post more details and pictures soon.


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PostPosted: Wed Oct 15, 2008 12:55 am 
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Jerry,

I understand you are sceptical. Like quite a few sailors tend to overestimate the windspeeds they are in, there are who underestimate the angle to the wind when close hauled. But I am talking about actual track and not just heading and I used shorelines to measure my progress. By the way, you are correct it could be more than 45 degrees since I only had less than an hour to test this, so it is quite possible that favourable turns in the wind fooled me without that effect filtered out. There was no hindering chop. It is an estimation, but I believe it was 50 degrees at most.

But, the alu sock "keel" was quite big, so this result probably isn't that sureprising. Unfortunately, it did not only worke like a daggerboard, but also as a break...

Do you happen to have pics of your leeboard?

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 Post subject: My rig.
PostPosted: Wed Oct 15, 2008 4:17 am 
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I'll take a pic of the leeboard, which should be made from 1/4" HDPE plastic, but a person could experiment with the other dimensions...I just picked 1' x 2' at random.

Below is a photo of my rig. More detailed image here:

http://img253.imageshack.us/my.php?imag ... ingjq5.jpg

The jugs with lead and water in them are to keep the bow down - Arizona Ice Tea or Treetop Apple Juice 1 gallon jugs tied together with a 1/4" nylon rope maybe 6" apart, then just layed over the bow as far forward as possible.

The jib is 1/2 of a Kmart shower curtain, cut diagonally, and is "ganged" to the mainsail, normally. I run a loop rope from SideKick to SideKick with a pulley running on it, then the jib sheet clips onto the pulley to hold the jib sheet down at a better sailing angle than if it was just connected directly to the mast. Also, this way, when not ganged (no rope extending behind the mast at all), the jib operates itself except occasionally I have to adjust the slack in the jib sheet depending upon how close to the wind I will be sailing.

Yes, I can raise and lower the sails and mast while out on the water...the rope is a continual loop that runs up from the stern, thru a slider at the top of the mast, then down to the bow through a pulley, then back along the hull to a quick-clip at the stern.

The sails furl up together onto the mast (not automatically!)...works well, but the rope rigging is complicated to get set up initially (one time).

The boom is a telescoping floor mop pole with a hook at each end (pole w/hook also comes in handy for grabbing onto things up front in the kayak that I can't reach from the rear seat).

skua wrote:
Jerry,

I understand you are sceptical. Like quite a few sailors tend to overestimate the windspeeds they are in, there are who underestimate the angle to the wind when close hauled. But I am talking about actual track and not just heading and I used shorelines to measure my progress. By the way, you are correct it could be more than 45 degrees since I only had less than an hour to test this, so it is quite possible that favourable turns in the wind fooled me without that effect filtered out. There was no hindering chop. It is an estimation, but I believe it was 50 degrees at most.

But, the alu sock "keel" was quite big, so this result probably isn't that sureprising. Unfortunately, it did not only worke like a daggerboard, but also as a break...

Do you happen to have pics of your leeboard?


Image
By soyjer at 2008-10-15


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PostPosted: Wed Oct 15, 2008 11:12 pm 
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See pics below.

skua wrote:
Jerry,

I understand you are sceptical. Like quite a few sailors tend to overestimate the windspeeds they are in, there are who underestimate the angle to the wind when close hauled. But I am talking about actual track and not just heading and I used shorelines to measure my progress. By the way, you are correct it could be more than 45 degrees since I only had less than an hour to test this, so it is quite possible that favourable turns in the wind fooled me without that effect filtered out. There was no hindering chop. It is an estimation, but I believe it was 50 degrees at most.

But, the alu sock "keel" was quite big, so this result probably isn't that sureprising. Unfortunately, it did not only worke like a daggerboard, but also as a break...

Do you happen to have pics of your leeboard?

Image
By soyjer at 2008-10-15

Image
By soyjer at 2008-10-15

Image
By soyjer at 2008-10-15

Image
By soyjer at 2008-10-15

Image
By soyjer at 2008-10-15


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 Post subject: Alu drive sock
PostPosted: Fri Oct 17, 2008 2:20 pm 
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Hi Jerry,

Thanks for posting all your pics and explanation. It is great to see your rig! Now I know it was you who inspired me to make my jib of a shower curtain. I like the fact that it is transparent and that it operates by itself. You've been very inventive! Fun to see a quite different solution for the problems I've also dealt with. Looks like the rear stay can interfere with the sail while tacking though. Is that the case?

I especially like your leeboard solution. The pictures are very helpful, they explain it all. Looks very simple and effective. Must try that out!

Stringy and others,
Here a few more details on the "alu drive sock" I experimented with. This is how it looks like:

Image

It 50cm long and just so wide that the drive fits. It is of a plate of 50x100cm of aluminium of 0,5mm thick, which is quite thin and bendable. But since I folded it a few times and put some plastic in it, it was stiff enough.

This is how the drive fits.

Image

As described above, the pointing was good, the tendency to slip sideways when trying to sail close hauled was simply gone (well, diminished to unnoticable). This also had its effect on the way my oasis behaved: with all that grip on the water it heeled MUCH more than with just the turbo's. There was not very much wind (Bft 3), but I had to lean strongly and still the sidekicks were much needed (normally with these winds it is easy to "lean" the side kicks out of the water). So it was clear the sock was actively working. The lee helm (caused by my jib) clearly seemed to be less than with only the turbos.

BUT, the show stopper is that it acted as a break. The performance was gone. Hardly any picking up speed in a gust. It just heeeeled. It went where I wanted, but much slower than I'm used to. The nice speeds (over 7km/h) that make sailing fun were completely unreachable. All the extra performance of my jib was killed by the sock. I made it too big. Or it could also be that the idea (a sleeve with drive in one open end) already adds to much drag.

Anyhow, if anyone want to make a drive sock himself, don't overdo it!

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 Post subject: Re: Alu drive sock
PostPosted: Fri Oct 17, 2008 2:49 pm 
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Yes, because the main sail is not a triangle, the upper part does catch on the rear stay, but I just cut off the baton (is that what that fiberglass stick up there is called?) flush with the edge of the sail, and I am able to shake the sail into jumping the past the rear stay when I tack, so it works out OK.

Yeah, try out my leeboard solution...maybe you can spend more time on yours so it doesn't look like it belongs in the kitchen like mine does!

I'm still waiting to be convinced that it is possible to do better than 70 degrees off the wind actual track in an Oasis. Speed and fun when going upwind mean nothing to me...I just want the option of sailing home upwind without waving to the same shore fisherman more than once on my way upwind!

Or I would like to know what factor disables a kayak from doing better than 70 degrees, if that is the case. I can't figure it out....needs more sail area?...needs the ability to lean more?....???

As far as the drive sock idea, I am too paranoid about hull drive mounting area stress...I won't even use Turbo Fins because I don't want to stress that area. Mine hasn't had any cracks...just being cautious.

I may be that along with the new Click and Go drive mounting system that the 2009 hull has been reinforced in that area and so maybe my concern is unjustified now? Anybody know?

Jerry

skua wrote:
Hi Jerry,

Thanks for posting all your pics and explanation. It is great to see your rig! Now I know it was you who inspired me to make my jib of a shower curtain. I like the fact that it is transparent and that it operates by itself. You've been very inventive! Fun to see a quite different solution for the problems I've also dealt with. Looks like the rear stay can interfere with the sail while tacking though. Is that the case?

I especially like your leeboard solution. The pictures are very helpful, they explain it all. Looks very simple and effective. Must try that out!

Stringy and others,
Here a few more details on the "alu drive sock" I experimented with. This is how it looks like:

Image

It 50cm long and just so wide that the drive fits. It is of a plate of 50x100cm of aluminium of 0,5mm thick, which is quite thin and bendable. But since I folded it a few times and put some plastic in it, it was stiff enough.

This is how the drive fits.

Image

As described above, the pointing was good, the tendency to slip sideways when trying to sail close hauled was simply gone (well, diminished to unnoticable). This also had its effect on the way my oasis behaved: with all that grip on the water it heeled MUCH more than with just the turbo's. There was not very much wind (Bft 3), but I had to lean strongly and still the sidekicks were much needed (normally with these winds it is easy to "lean" the side kicks out of the water). So it was clear the sock was actively working. The lee helm (caused by my jib) clearly seemed to be less than with only the turbos.

BUT, the show stopper is that it acted as a break. The performance was gone. Hardly any picking up speed in a gust. It just heeeeled. It went where I wanted, but much slower than I'm used to. The nice speeds (over 7km/h) that make sailing fun were completely unreachable. All the extra performance of my jib was killed by the sock. I made it too big. Or it could also be that the idea (a sleeve with drive in one open end) already adds to much drag.

Anyhow, if anyone want to make a drive sock himself, don't overdo it!


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PostPosted: Fri Oct 17, 2008 8:35 pm 
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Thanks for posting your mods Jerry and Skua. It's always good to see the inventiveness of others! 8)
Jerry- I like your leeboard mounting. I was going to try something similar before I got my AI!
If you look closely at the Hobie daggerboard it is narrower, longer and carefully shaped on both leading and trailing edges to make them much thinner. It slips through the water easily.
I have used Turbo's on my Oasis for over a year and have had no drivewell problems. The new click and go system is supposed to be stronger and eliminates the cam bolt columns which some have reported trouble with. Did I read on KFS that you have had your hull replaced?

Skua- shame about the brake effect of your sock. All is not lost though. You now have a very nice protective sleeve when transporting your drive! :wink:
Next time I put the Oasis in I'll try to get some accurate angles for upwind sailing using a compass.


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PostPosted: Fri Oct 17, 2008 9:02 pm 
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Compass?...when I said I want proof of better than 70 degrees off the wind, I meant signed affidavits from shore fishermen along your route that you only passed by each of them once on your trip upwind!

For me it's easy, because the lake I sail on is only 1 mile wide and 3 miles long, and the wind blows right down the length of the lake.

Yes, I've had some minor problems with cracking in-between the rear seat and the rear hatch, but no drivewell cracking...I'm just the cautious type, that's all.

stringy wrote:
Thanks for posting your mods Jerry and Skua. It's always good to see the inventiveness of others! 8)
Jerry- I like your leeboard mounting. I was going to try something similar before I got my AI!
If you look closely at the Hobie daggerboard it is narrower, longer and carefully shaped on both leading and trailing edges to make them much thinner. It slips through the water easily.
I have used Turbo's on my Oasis for over a year and have had no drivewell problems. The new click and go system is supposed to be stronger and eliminates the cam bolt columns which some have reported trouble with. Did I read on KFS that you have had your hull replaced?

Skua- shame about the brake effect of your sock. All is not lost though. You now have a very nice protective sleeve when transporting your drive! :wink:
Next time I put the Oasis in I'll try to get some accurate angles for upwind sailing using a compass.


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PostPosted: Wed Oct 22, 2008 12:27 pm 
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soyjer wrote:
I'm still waiting to be convinced that it is possible to do better than 70 degrees off the wind actual track in an Oasis.

Well, if you want to be convinced, make a brake, sorry drive sock my style or a leeboard that draws at least 70cm deep. You will notice the difference!


stringy wrote:
Skua- shame about the brake effect of your sock. All is not lost though. You now have a very nice protective sleeve when transporting your drive! :wink:

Very comforting Stringy! :lol:


stringy wrote:
Next time I put the Oasis in I'll try to get some accurate angles for upwind sailing using a compass.


It would be great if you go try the upwind sailing angle you are able to achieve with your oasis (actual track). If you feel like experimenting, you could try with and without your daggerplug in the front drive slot, and also with nothing in the front drive slot and the daggerboard in the aft drive slot (maybe also front sail furled). I look forward to hear your reports!

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PostPosted: Wed Oct 22, 2008 4:47 pm 
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Yeah...I think my leeboard is too short...maybe a 1' x 3' would be better. Also, it ain't exactly hydrodynamic...it's more shaped for cutting up onions, I think. Eventually I'll try a longer (deeper) one, I think.

skua wrote:
soyjer wrote:
I'm still waiting to be convinced that it is possible to do better than 70 degrees off the wind actual track in an Oasis.

Well, if you want to be convinced, make a brake, sorry drive sock my style or a leeboard that draws at least 70cm deep. You will notice the difference!


stringy wrote:
Skua- shame about the brake effect of your sock. All is not lost though. You now have a very nice protective sleeve when transporting your drive! :wink:

Very comforting Stringy! :lol:


stringy wrote:
Next time I put the Oasis in I'll try to get some accurate angles for upwind sailing using a compass.


It would be great if you go try the upwind sailing angle you are able to achieve with your oasis (actual track). If you feel like experimenting, you could try with and without your daggerplug in the front drive slot, and also with nothing in the front drive slot and the daggerboard in the aft drive slot (maybe also front sail furled). I look forward to hear your reports!


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PostPosted: Sun Oct 26, 2008 8:12 pm 
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Skua and Jerry,
Took the Oasis out solo on Saturday. First time soloing with the two sails since I got my AI! It was only for a short time as I got a call when on the water requesting me to come into work. :(
Anyway, I was able to record my exact track using my Nokia Navigator GPS phone and their great little program called Sports Tracker. It logs your route, speed, distance and time and allows you to export as a Google Earth KML file. 8)
The wind was a steady NE at 15-17 knots and I was trying to see just how it pointed with two sails, front daggerboard down and only pedaling through a tack. I was trying to sail as close as possible keeping the sails from luffing (just!) When I got the call the wind was picking up so I took the sails down and pedaled back as I was pushed for time and couldn't afford a capsize!
The results (which should be more accurate than a compass :wink: ) are below:

Image
I'll post more results for future trips when I can. It will be interesting to compare the Oasis to the AI!


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PostPosted: Tue Oct 28, 2008 2:05 pm 
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Thanks Stringy, for this data. I don't know of a better way to present the actual track!

If I look at it I can see you do very well with your setup. Also I guess there were some changes in wind direction (on some parts of the track the wind must have been more from the east than on others; probably also the mean wind direction was a little more from the east than the red arrow suggest).
But much more important: I think we can conclude you are able to do within 50 degrees, probably close to 45. And that is very good for a kayak; what many touring sail boats do is of that same order. True upwind sailing capability indeed!

Personally, I am not really surprised you could get this out of your oasis (with your daggerboard in the front drive slot). My drive-sock experience learned me that this must be possible in principle. But this is the evidence!

PS: Did you sail with both sails fully unfurled or furled a little? 15-17 knots of wind is quite a lot with the two sails up (and without sidekicks!). Over 12 knots (mean) wind I only use my main and over 17 I would start to furl my main partly if I could...

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PostPosted: Wed Oct 29, 2008 3:19 am 
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G’Day Skua,
I think your observations are spot on. 8)
The wind probably was a bit more ENE and it was too strong for both sails fully out but I was keen to test upwind tracking. Without outriggers it is easier sailing into a strong wind than across or down wind which is why I dropped the sails on my return. I wouldn’t have had both sails fully out in those conditions normally if I was just out for a pleasant sail. In fact I didn’t really enjoy this test. I was concentrating so much on staying upright and hiking out that I quickly tired. :(
The AI has spoiled me and this test made me realise that I need to add outriggers to the Oasis if I’m to get that same easy sailing as the AI!


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