blacklionboy
New Member
is sanding your centreboard and rudder worh it? is it legal.? i heard that the world champion does each time he goes out. and that his they are constantly orange
Sanding centreboard and rudder
- Thread starter blacklionboy
- Start date
49208
Tentmaker
IIRC, the blades are supplied at the Worlds and you are not allowed to sand them. The point of telling you that, is if someone wins the worlds in a stock setup, it's should show that it's not the condition or shape of his own blades that makes him fast.
You can refinish the surface of your blades. The rules tell you clearly how far away from the trailing edge you may taper the blades. See the rules for full details on both of these.
Is it worth it ? Well if your foils are covered with deep scratches, nicks and bumps, or the trailing edges are uneven or wavy, then yes it's worth it.
IMHO, I question those that take perfectly straight trailing edges and then try to hand taper them to sharpen or reduce the thickness of the trailing edge. You've got a 50/50 chance of screwing it up by changing. Unless the blade was really humming, I don't see the point of tapering the trailing edge on a blade that is straight and not humming.
You can refinish the surface of your blades. The rules tell you clearly how far away from the trailing edge you may taper the blades. See the rules for full details on both of these.
Is it worth it ? Well if your foils are covered with deep scratches, nicks and bumps, or the trailing edges are uneven or wavy, then yes it's worth it.
IMHO, I question those that take perfectly straight trailing edges and then try to hand taper them to sharpen or reduce the thickness of the trailing edge. You've got a 50/50 chance of screwing it up by changing. Unless the blade was really humming, I don't see the point of tapering the trailing edge on a blade that is straight and not humming.
jamesfreedman
New Member
Are you slower then most your competitors? I just throw my boards in the boat and they are all scuffed up. I think my centerboard may be warped. I dont really care because that is not the problem. The problem comes everytime I miss a shift, get a bad start, have a bad mark rounding, etc. It would be better time spent on the water practicing then sanding. I knew a guy who was always cleaning his boat everytime I went sailing. Most the time he sailed in the back of the fleet.
ILCA Rules: http://www.laserinternational.org/rules/rules07.pdf
14. CENTREBOARD
(a) A rope handle passing through not more than two holes of maximum diameter 12.5 mm above a line drawn from the bottom of the centreboard stop, parallel to the top of the centreboard is permitted. A plastic/rubber tube and/or tape are permitted on the handle of the centreboard.
(b) The trailing edge of the centreboard may be sharpened by sanding the blade between the trailing edge and a line 100 mm parallel to the trailing edge, provided the distance between the leading edge and the trailing edge of the blade is not reduced.
(c) Surface refinishing of the centreboard is permitted provided the original shape, thickness and characteristics are not altered.
(d) One layer of general purpose self adhesive plastic tape (includes duct and gaffer tape) of maximum 2mm thickness and of a maximum size of 30mm x 30mm may be applied at the top front corner of the centreboard case.
(e) A wood centreboard shall not be used on a hull that was originally supplied with a non wood centreboard.
(f) A tie line or shock cord shall be attached to the small hole in the upper forward corner of the centreboard, and any of the bow eye, the cunningham fairlead, the "Builder Supplied" deck block fitting and the mast to prevent loss of the centreboard in event of a capsize. The tie line or shock cord may be looped around the bow, but shall not be attached to the gunwale. Attachment can be by knots or loops in the shock cord, and/or tie lines, shackles, clips, hooks or eyes.
(g) The components of the "Builder Supplied" centreboard stopper may be secured together by glue, screws, bolts, nuts and washers, provided the original shape and dimensions are not reduced.
15. RUDDER
(a) The trailing edge of the rudder blade may be sharpened by sanding the blade between the trailing edge and a line 60 mm parallel to the trailing edge, provided the distance between the leading edge and the trailing edge of the blade is not reduced.
(b) Surface refinishing of the rudder blade is permitted provided that the original shape, thickness and characteristics are not altered.
(c) The rudder blade and/or rudder head holes may be enlarged up to a maximum diameter of 10mm. The rudder bolt and bush set may be replaced with a larger diameter bolt to fit this hole. The bolt head, nut and washers shall fall within a 20mm diameter circle.
(d) To achieve the maximum 78 degree rudder angle relative to the bottom edge of the rudder head, the leading edge of the blade may be cut away where it touches the spacing pin.
(e) To restrict the rudder angle to maximum 78 degrees relative to the bottom edge of the rudder head, the lower forward spacing pin shall be wound with flexible adhesive tape.
(f) The rudder pintles may be fitted with spacers to lift the rudder head to allow the tiller to clear the deck at the transom.
(g) The rudder downhaul line may have multiple purchases.
(h) A hole may be drilled in the top rudder pintle and a pin or clip inserted in the hole to prevent loss of the rudder.
(i) [FONT=Arial,Arial]A wood rudder shall not be used on a hull that was originally supplied with a non wood rudder. [/FONT][FONT=Arial,Arial][/FONT]
This is true but if they all don’t have their boards 're-finished' then they are all going the same speed.. Who is to say that if Joe Blo goes out against the current world champion with a set of boards that have been 'tweaked' that he wont walk all over him??
IMHO unless your boards are scratched up to buggary then it really isn’t going to make that much difference. The worst thing that will happen if your trailing edge is all messed up or your board has some cool scratches on it then when you are going quick enough then you 'may' get flow separation due to this and cavitation as a result from going from a nice laminar flow to a turbulent.. Also you don’t want a 'perfect' trailing edge as then you will get vortex shedding on alternate sides. A great example of this is a wooden post in the river when the current is really honking you will see the post wobble from side to side as the vortex sheds of each side alternately..
But I am more worried about going the right way and staying upright!
With respect, as I seem to be getting in to trouble lately for my questions and comments. There were a bunch of blades/foils that hit the shops which were straight/flat down one side, massive disadvantage so they had to be changed.
If the rules allow and they do (rules 14b,c and 15a,b) How is it that at the worlds you can't change them? Just wondering anyway.... Rules are rules.....for some groups.
bjmoose
Member
I can't speak to the specifics, as I've never been to a Laser Worlds event.
But it's relatively easy to write a policy such as that into the NOR and SIs, and then it becomes part of the rules of the event.
49208
Tentmaker
I think we are talking apples and oranges in the first part - When I meant straight blades, I meant the trailing edge wasn't wavy or warped, and the board was symmetric. I think you are talking about asymmetric blades where one side is shaped differently. I agree with you in that case, getting the blade replaced or reshaping it so it is symmetric is called for.
As far as the Open Worlds, as noted above, the NOR/SI's are modified such that the supplied boat, sail, spars and blades must be used "as is" ie, no modifications are allowed. The goal is to make the competition as much a test of sailor vs sailor as possible.