Flying Monkey
New Member
I have a new racing sail, I need to put ticklers on it, can someone refer me to a website with a diagram, or something like that.
Thanks
Thanks
Tell Tale/Tickler placement
- Thread starter Flying Monkey
- Start date
drLaser
Member
I wonder why nobody replied to this question. Not even Will!
Maybe because the author did not want to grace us with his name.
In any case, you can find much about this on the drLaser website's "Boat Handling" section.
Available are a distribution of the telltale locations used by all the hot-shots who competed in the 2002 Laser World Championships (Hyannisport, USA) , plus a series of discussions between sailmaker Mikko Brummer and aerodynamicist Arvel Gentry about the use of (sequential short) "tufts" rather than telltales.
URL: http://www.drLaser.org
or to go directly to the "Boat Handling" section, use
http://www.drLaser.org/frm/plfBHCf.html
and selecet the articles from the pull-down menu on top. If your JavaScipt is off, you can click on the "Boat Handling" headline.
Shevy Gunter
Editor, drLaser
Maybe because the author did not want to grace us with his name.
In any case, you can find much about this on the drLaser website's "Boat Handling" section.
Available are a distribution of the telltale locations used by all the hot-shots who competed in the 2002 Laser World Championships (Hyannisport, USA) , plus a series of discussions between sailmaker Mikko Brummer and aerodynamicist Arvel Gentry about the use of (sequential short) "tufts" rather than telltales.
URL: http://www.drLaser.org
or to go directly to the "Boat Handling" section, use
http://www.drLaser.org/frm/plfBHCf.html
and selecet the articles from the pull-down menu on top. If your JavaScipt is off, you can click on the "Boat Handling" headline.
Shevy Gunter
Editor, drLaser
will162878
New Member
Will did not reply because the last time Will wrote "drlaser.org" the "drlaser" bit appeared as "*******"...
Obviously that isn't the case anymore.
Thanks for using the forum.
Thanks for using the forum.
will162878
New Member
Glad to hear it.
One other point i would make is that if you sail downwind by the lee, don't place tales too close to the luff, because mast turbulence will make them useless by the lee. Also, if you find kicker tuning difficult to get right, and you have the adjustability of the 2001 system, place a telltale on the leech end of the top batten pocket.
One other point i would make is that if you sail downwind by the lee, don't place tales too close to the luff, because mast turbulence will make them useless by the lee. Also, if you find kicker tuning difficult to get right, and you have the adjustability of the 2001 system, place a telltale on the leech end of the top batten pocket.
drLaser
Member
We all know that when we sail by the lee, the leech becomes the entry point and the luff becomes the exit point of the windflow (i.e., windflow is from leech to luff).
As such, the luff telltales have little or no value added for sail trim when by the lee. It's the leech telltales that give the greatest bits of information.
And that's why instead of having a single telltale mounted exactly on the leech, you need two separate telltales (to port and starboard sides) mounted 5 to 10" (12 - 25 cm) forward of the leech.
Furthermore, having these leech telltales just at the height of the top batten pocket (the standard location for checking vang setting when NOT by the lee) is not suffifient for by the lee sailing. Due to the significant differences in the "angle of attack" at different heights along the leech, at least one more set of (port/starboard) lower leech telltales are desirable for by the lee sailing.
Whether the luff telltales are too close to the mast is irrelevant for by-the-lee sailing. That's because wind tunnel images show that when by the lee, a round mast with a sleeved sail creates no turbulance right near the mast. If the attached windflow ever gets sufficiently close to the mast without separation (as with a smaller draft and in reasonably high winds), the flow is always smooth around the sleeve, with turbulance created only behind the mast, behind the trailing edge of the airfoil (which is not of significance).
Instead of any luff telltales, a separate telltale set right forward of the max-draft location helps with sail, vang and outhaul trim when by the lee.
Then again, a great Laserite I know sails with no telltales at all. Even at Cooper River (New Jersey), a place notorious for its unpredictable shifts and velocity changes.
Shevy
As such, the luff telltales have little or no value added for sail trim when by the lee. It's the leech telltales that give the greatest bits of information.
And that's why instead of having a single telltale mounted exactly on the leech, you need two separate telltales (to port and starboard sides) mounted 5 to 10" (12 - 25 cm) forward of the leech.
Furthermore, having these leech telltales just at the height of the top batten pocket (the standard location for checking vang setting when NOT by the lee) is not suffifient for by the lee sailing. Due to the significant differences in the "angle of attack" at different heights along the leech, at least one more set of (port/starboard) lower leech telltales are desirable for by the lee sailing.
Whether the luff telltales are too close to the mast is irrelevant for by-the-lee sailing. That's because wind tunnel images show that when by the lee, a round mast with a sleeved sail creates no turbulance right near the mast. If the attached windflow ever gets sufficiently close to the mast without separation (as with a smaller draft and in reasonably high winds), the flow is always smooth around the sleeve, with turbulance created only behind the mast, behind the trailing edge of the airfoil (which is not of significance).
Instead of any luff telltales, a separate telltale set right forward of the max-draft location helps with sail, vang and outhaul trim when by the lee.
Then again, a great Laserite I know sails with no telltales at all. Even at Cooper River (New Jersey), a place notorious for its unpredictable shifts and velocity changes.
Shevy
will162878
New Member
Who sails by the lee and has time to look at telltales in a 15kt breeze, with big waves and no vang/kicker tension???
drLaser
Member
Dear Will,
Your previous post dated 05/08 was about where to place telltales for by the lee sailing, if I'm not mistaken. Therefore, I did not understand the nature of your last comment at all.
Shevy
Your previous post dated 05/08 was about where to place telltales for by the lee sailing, if I'm not mistaken. Therefore, I did not understand the nature of your last comment at all.
Shevy