89er
- Thread starter JulianB
- Start date
Beat me to it. My square head is bigger than yours, ~2.36 m, (about the only thing I can brag about) so I will let you know how it goes, when I can get around to it. I was planning on 120 degree winglets as well, pinned to the gaff batten somehow.
Decided to go really small and see what happened. This thing is probably 250mm f-a and CL to tip 100mm, (there is another out the other side) I got some Vee-blocks made (3D printed) that hold them all at 120°.
My problem is that in more than 8-10 knots of breeze, my hands are literally full, with my eyes outside the boat reading the wind for gusts and shifts to keep the ama just flying without capsizing. I could do with a knowledgeable trimmer watching the sails.
BTW, my name is Rob, not Rod.
Love your clean slick sails…….
Last edited:
JulianB
Super Anarchist
- Thread starter
- #1,104
My 3D printed Vee-block, fat slot (4mm wide) at the bottom, goes on the existing sail.
The 2 thin ones, (1mm wide) go on the wing-let blades, mine are 0.3mm thick carbon plate with sticky back around the edges.
Lug/hole at the top is for 3mm shockcord fwd, to hold it in place, while sailing, then you just pull it off when you roll the sail, and the wing-let blades fold flat!
PM me your address and I can send you down one, I have a few spare!
chris foiler
Member
That is really neat a double horners tip that folds
JulianB
Super Anarchist
- Thread starter
- #1,106
Got a few of you asking what the B2B [Bay to Bay] race is.
Now I have not done this for maybe 10 years, you start down near Tin Can Bay Marina, and you sail up the Great Sandy Strait, over night at Stewart Island, which is the 1st island big island above the G in the place name Great Sandy strait, then very early start Sunday and race up to Hervey Bay YC, which is the boaty looking one, in the middle at the top. It's a 90km (approx 47nm tight string) race, a lot of navigation because it's shallow up the strait, Fraser Island is the largest sand island in the world I believe, and quite flat, and the wind tends to blow down (god helps us) or up the strait. Both Shane (Fairweather) and Brad (Taylor) have done it a few times, and Shane shoudl be great at navigation. We have 2 young bucks (Will Bridge & Ben Roxburgh) onboard for boy power.
Tin Can Bay is a 2 hr drive north of Brisbane, Hervey Bay is 3hrs north.
Now I have not done this for maybe 10 years, you start down near Tin Can Bay Marina, and you sail up the Great Sandy Strait, over night at Stewart Island, which is the 1st island big island above the G in the place name Great Sandy strait, then very early start Sunday and race up to Hervey Bay YC, which is the boaty looking one, in the middle at the top. It's a 90km (approx 47nm tight string) race, a lot of navigation because it's shallow up the strait, Fraser Island is the largest sand island in the world I believe, and quite flat, and the wind tends to blow down (god helps us) or up the strait. Both Shane (Fairweather) and Brad (Taylor) have done it a few times, and Shane shoudl be great at navigation. We have 2 young bucks (Will Bridge & Ben Roxburgh) onboard for boy power.
Tin Can Bay is a 2 hr drive north of Brisbane, Hervey Bay is 3hrs north.
JulianB
Super Anarchist
- Thread starter
- #1,107
Hi being asked for a 3d print file for my Y block for the winglets.
This is the existing;
And it wont let me up load 3dm, igs, stp & stl files so you have to PM me if you want them.
and I have upgraded what I am thinking, stronger, lighter, neater and less open to abuse.
You can have either file.
jB
This is the existing;
And it wont let me up load 3dm, igs, stp & stl files so you have to PM me if you want them.
and I have upgraded what I am thinking, stronger, lighter, neater and less open to abuse.
You can have either file.
jB
JulianB
Super Anarchist
- Thread starter
- #1,108
Hi guys,
zks7, I have sent you some files already, but I will send them to you in stl. which seems to be the preference for cottage industry 3D printing.
I work in Rhino, few reason I chose that, they are all the same in price at the end of the day, but I am semi fluent in Rhino and way too old to changes horses now. So the base file will be 3dm.
zks7 has also asked how I made the actual wing-let, again it's mostly a single layer of 300gm carbon plate, wet-jet cut out and then stuck together with "sticky-back" sail cloth tape. That acts as the hinges, also the edges of the carbon plate are very sharp, so the material around the sides is there to dull that sharpness.
If we believe it continues to have a positive effect on our performance I may get it sewn on, at present, it's just "sticky-backed" on.
Very full day today on 49er masts, later this afternoon I will bring DP home, in anticipation of the drive north, and I will endevour to get you some more happy snaps of the whole wing-let tomorrow.
jB
zks7, I have sent you some files already, but I will send them to you in stl. which seems to be the preference for cottage industry 3D printing.
I work in Rhino, few reason I chose that, they are all the same in price at the end of the day, but I am semi fluent in Rhino and way too old to changes horses now. So the base file will be 3dm.
zks7 has also asked how I made the actual wing-let, again it's mostly a single layer of 300gm carbon plate, wet-jet cut out and then stuck together with "sticky-back" sail cloth tape. That acts as the hinges, also the edges of the carbon plate are very sharp, so the material around the sides is there to dull that sharpness.
If we believe it continues to have a positive effect on our performance I may get it sewn on, at present, it's just "sticky-backed" on.
Very full day today on 49er masts, later this afternoon I will bring DP home, in anticipation of the drive north, and I will endevour to get you some more happy snaps of the whole wing-let tomorrow.
jB
Bill E Goat
Super Anarchist
Julian
Do you think it would work on the 18's ?
Do you think it would work on the 18's ?
JulianB
Super Anarchist
- Thread starter
- #1,110
The sails that the 18teens are running these days are 10-12% bigger than those we ran back in the 90's with 17ft wings. Sure the AWS is lower, and maybe that's why they do it.
But my guess is the pressure loading "differential" on the sails is in fact very low.
Further the way that they have the top aft edge up above the fwd (main-head) would either exacerbate of negate the vortex, I don't know which one without looking closely at it, which I have not done.
So, 1st thing they would have to do, is cut back a section so it was horizontal (Asko and Yamaha heads where roughly horizontal), then you would need to work out whether the drag from the additional wing-lets was beneficial (as in stopping the vortex) or not.
With DP, the head is moderate, bigger than I would have done, but again, Andy did an amazing job. Both GT and Jimmy said there where spirals, as in the tuff did circles. I did not see that, but if it did, then what we have done on DP which is very minimal should drop drag.
Bill E Goat, just me saying that I simply don't know!
But my guess is the pressure loading "differential" on the sails is in fact very low.
Further the way that they have the top aft edge up above the fwd (main-head) would either exacerbate of negate the vortex, I don't know which one without looking closely at it, which I have not done.
So, 1st thing they would have to do, is cut back a section so it was horizontal (Asko and Yamaha heads where roughly horizontal), then you would need to work out whether the drag from the additional wing-lets was beneficial (as in stopping the vortex) or not.
With DP, the head is moderate, bigger than I would have done, but again, Andy did an amazing job. Both GT and Jimmy said there where spirals, as in the tuff did circles. I did not see that, but if it did, then what we have done on DP which is very minimal should drop drag.
Bill E Goat, just me saying that I simply don't know!
Bunchofgrapes
New member
- 38
- 9
...or any other high performance skiff with a square top main for that matter.
JulianB
Super Anarchist
- Thread starter
- #1,112
49er has a SCP of about 71-72kgs.
It has a (working) sail area of 22m².
So those sails are loaded 3.27kgs/m².
DP has a SCP of approx 150kgs
Has a (working) sail area of 45m²
So those sails are loaded 3.33kgs/m²
Sure, a lot of that load is in the bottom 1/3, as it should be, main and jib (as in slot), well end-plated yad yad yad.
So if we had spirals happening on DP, and all other things being equal, then very probably there will be spirals on a 49er, so some level of wing-let would probably work very well on a 49er.
The WING also has wing-lets and the feedback there was significant.
29erC in China, had wing-lets also, but I have no data/feedback on that.
FX, down 25% on SCP, and probably down that in SA, plus shorter ARM so very likely to benefit from wing-lets. (more so that 49er)
I14, less likely, more sail area, less SCP, so less loading, so less pressure differential.
Skate, huge SCP, compact sail plan, highly probably benefit from wing-lets.
Current 18teen, I'm guessing is likely to be similar to the I14, also on following them the upper leach "hangs way off" as it would have to, so less likely to benefit.
Before everyone jumps on the band-wagon, I don't have any "proof" that they do anything yet other than look horny.
All we have is GT and (the other) JB (jimmy Beck) saying there are less spirals
It has a (working) sail area of 22m².
So those sails are loaded 3.27kgs/m².
DP has a SCP of approx 150kgs
Has a (working) sail area of 45m²
So those sails are loaded 3.33kgs/m²
Sure, a lot of that load is in the bottom 1/3, as it should be, main and jib (as in slot), well end-plated yad yad yad.
So if we had spirals happening on DP, and all other things being equal, then very probably there will be spirals on a 49er, so some level of wing-let would probably work very well on a 49er.
The WING also has wing-lets and the feedback there was significant.
29erC in China, had wing-lets also, but I have no data/feedback on that.
FX, down 25% on SCP, and probably down that in SA, plus shorter ARM so very likely to benefit from wing-lets. (more so that 49er)
I14, less likely, more sail area, less SCP, so less loading, so less pressure differential.
Skate, huge SCP, compact sail plan, highly probably benefit from wing-lets.
Current 18teen, I'm guessing is likely to be similar to the I14, also on following them the upper leach "hangs way off" as it would have to, so less likely to benefit.
Before everyone jumps on the band-wagon, I don't have any "proof" that they do anything yet other than look horny.
All we have is GT and (the other) JB (jimmy Beck) saying there are less spirals
zks7
Anarchist
Julian,
The files sent are the attachment points to the sails and the "wings". Is that correct? If so, how long and wide are the carbon "wings"? Any idea of dimensions of the wings and why you chose those lengths?
When we get them produced, they will be taken to a low speed(under 15 knots) wind tunnel. Interesting to see if we can measure the drag and hopefully get some (smoke) pictures of vortices - before and after winglet application.
Practical application will be targeted for a 24 foot sport boat.
This is just for fun, not part of any project. Not expecting to have much noticeable(to the helm) effect - more like intellectual curiosity.
- Z
The files sent are the attachment points to the sails and the "wings". Is that correct? If so, how long and wide are the carbon "wings"? Any idea of dimensions of the wings and why you chose those lengths?
When we get them produced, they will be taken to a low speed(under 15 knots) wind tunnel. Interesting to see if we can measure the drag and hopefully get some (smoke) pictures of vortices - before and after winglet application.
Practical application will be targeted for a 24 foot sport boat.
This is just for fun, not part of any project. Not expecting to have much noticeable(to the helm) effect - more like intellectual curiosity.
- Z
You mean a bit like this:
And could explain why some old gaffers were pretty good for their time, complete with endplate spars:
Bunchofgrapes
New member
- 38
- 9
I am all for looking horny....
Jethrow
Super Anarchist
I always used to think it strange that the Mirabaud boat used to do rig upgrades looking for performance, but actually went backwards in aero, changing from a small hull to that tube thing with pipes and struts and bags and wires all over the place!
JulianB
Super Anarchist
- Thread starter
- #1,117
OK, I am going to let the pictures do the talking.
If you need anymore embellishment, ping me!
At the moment it's just stuck on with sticky back tape.
Later I may get a row of stitching down it!
I have added some tufts to see whats happening during the B2B, not sure it's hi priority.
That tuft that GT & JB#2 said where doing spirals is about 300mm down from the wing-let.
So these wing-lets and the 120° clip were rolled up in the sail for 10 days, before I pulled them out, no issue, the carbon plate is 0.5mm thick, you can cut it with domestic scissors.
I get it cut in HK with a water jet. The rest is just stick-back, 1.5oz I think, garden variety stuff.
If your stuck, I think there are about 20 bits of carbon in HK pre-cut to this size.
If you need anymore embellishment, ping me!
At the moment it's just stuck on with sticky back tape.
Later I may get a row of stitching down it!
I have added some tufts to see whats happening during the B2B, not sure it's hi priority.
That tuft that GT & JB#2 said where doing spirals is about 300mm down from the wing-let.
So these wing-lets and the 120° clip were rolled up in the sail for 10 days, before I pulled them out, no issue, the carbon plate is 0.5mm thick, you can cut it with domestic scissors.
I get it cut in HK with a water jet. The rest is just stick-back, 1.5oz I think, garden variety stuff.
If your stuck, I think there are about 20 bits of carbon in HK pre-cut to this size.
zks7
Anarchist
Julian,
Where does the forward end of the bungee cord attach? To the stick back tape?
Address of the HK (Hong Kong?) precut carbon wing source?
- Z
Where does the forward end of the bungee cord attach? To the stick back tape?
Address of the HK (Hong Kong?) precut carbon wing source?
- Z
