Laser - My Mast Rake.
So Lasers are one design? Well almost. There are build tolerances that make small differences to your speed from mast rake, spar stiffness and weight. Also having sailed a Europe dinghy very seriously, I also know the effect of mast rake on performance. In light winds, Europe sailors used to rake aft so that the sail kissed the aft deck with just the right amount of leach tension. Then they moved the mast forward for maximum leach tension as the wind increased. Then - well then if you had a bendy mast - further forward still to hold the leach - or if you had a stiff mast, further back to open the leach. The key consideration for the Europe was to keep the boom as close to the aft deck as possible. Europe and Finn sailors talk about edge effect, where the sail and deck can work together, but certainly from my experience in Laser Standard and Laser Radial sailing, the sooner I was able (when saying able - I mean using the sail controls to give best sail shape - but still the word is able) to get the main block to block, the quicker I was in the lighter conditions. I have sailed Lasers with the rake too far forward - It was slow in light winds, I tended to over bend the upper mast to get the boom to block to block. The boat would pitch or bob upwind in waves. Strangely with the mast too far forward, I also found the weather helm increase? That might sound strange but if you tighten the leech more and suck the fullness out of the luff - then the boat will feel heavier on the helm. To mitigate this, I would select a bendy lower mast (how to find a bendy one? ANS: weigh it or take some callipers to the section. Thicker wall or larger section = stiffer) My first laser had a very aft rake (3795mm). I won a few races at my first Standard Europeans and came 3rd in my first Laser Nationals in 1993 - I was a rocket ship in light to moderate winds - but pretty rubbish in a breeze - but that might have been me.. From my Europe dinghy experience, we used to push the mast forward for flat water and aft for wave sailing. Although we can't adjust our mast rake on the Laser - we at least can be aware of its rake and how to mitigate its rake with the spars that we have to choose from. So let's see how you could measure the mast rake on a Laser, then discuss the relative merits of some extremes, and by that I mean extremes as the builders are normally very good at keeping within a cm of what we would call a good mast rake.
To measure your mast rake you will need to attach a tape measure to the top of your standard lower mast (I use electrical pvc tape).
Sorry if you are a radial sailor, you will have to borrow a standard mast. Make sure the lower mast is straight. Put the mast in the boat and then take the tape measure to the back of the boat - making sure the tape is not twisted and has a good lie to the transom. Where the tape kisses the back deck is where you measure your rake number.
This one reads 3m 82cm - or if you are technical - it reads 3820mm. Give or take a couple of mm. In fact my tape measure is probably a couple of mm proud of the top of the mast so its perhaps really 3818mm. Good mast rakes: This depends on the version of Laser you are sailing: 4.7. After seeing the variance in lower mast bends (they should be 15 degrees) its perhaps hard to call this one. But if you have lots of lower mast bend - then more upright (less rake) or larger number might be better. Do check your lower mast bend though. If you have a section with lots of bend, you might want to change it if you are planning to sail in all conditions. It should be 15 degrees, my feeling is that less bend will give you more power in the light to moderate and too much power in the breeze. Radial. The problem with the radial is all the spars are stressed to (or even beyond) their elastic limit. Too upright (larger number) and the spars bend permanently, too raked (small number) and you have no leach tension. Spars have changed significantly. Lower masts can be bendy or stiff. Personally I prefer the lower mast to be on the bendy side and the upper mast to be about 2.85Kg. I find that when the upper mast gets too stiff, then the leach looses contact with the wind. I like a mast rake of about 3820mm - so I am pretty happy with this new ship. Standard sailors tend to like stiff upper masts. As a rather short 5'8" standard sailor I used to select lower masts that were rather bendy so I could vang on hard in the breeze. My first standard laser had a rake of 3795mm, which was great in the light but not competitive in medium or strong winds. Much more than 3830 and I feel that I could not get the boom block to block. Again - this depends on the spars you have to choose from. A very bendy lower mast might be ideal with a 3830 mast rake - but you would also need a very stiff upper mast to maintain the upper mast sail profile. I think 3835mm is a bit uncomfortable to sail a radial - as the weather helm gets hard and my biceps start screaming. Its also pretty hard to get to block to block. My charter boat at the Laser Worlds in Terrigal had a mast rake that was 3860mm. It was a pig. There was no fullness or power in the upper leach and the wind appeared to not stick to the sail through the wave pattern. This boat did not have a great pedigree. The Standard sailor who had podiumed at the Olympics the previous year, did not make the top 50 of these worlds. If you are going to get choosy about the mast rake, you have to know what spars are available. Aussie boats were traditionally further forward than European boats - but they also had super bendy standard lower masts and stiff upper masts - which gave them a further forward mast for going downwind and a more even curve over the two spars. Put UK spars on an Aussie boat (Aussie boats had a mast rake of 3830mm) and you have way too much upper mast bend which sucks the power out of the luff and opens the leach. The softer lower mast allows the upper mast to stay relatively powerful and hold its depth. I think that LP have achieved a great standard in mast rake at the moment with some super stiff upper masts for Standard sailors. As a radial sailor, I think I am looking for a more bendy upper mast than a standard sailor and as bendy a lower mast that I can find. Next job - fit a Rooster Pro Plus Laser Toestrap and Toestrap Adjustment Pack, New Rules. Then.. time to test the new ship for real....
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