|24th May 2010 10:54 PM|
|Deja Vu||BD uses a low boom and he's done O.K. Photos of people sailing are deceptive as far as boom height is concerned, since their body position may make the boom appear higher than it actually is. If you're comfortable, whatever the boom height (within reason), then you're probably faster.|
|19th May 2010 12:57 AM|
I like the feel of a boom set somewhere between the shoulders and chin.
I've had old school guys claim that forehead height was once the rule of thumb.
Any discipline that's concerned with power, formula, freestyle, slalom, goes with a high boom.
Maximum height should give the best power transfer, as it's closer to the sail's center of effort. Less power is wasted in the form of mast flexing. When your sail is on the max downhaul settings, and the COE is low and backhanded, a raised boom can enhance your leverage over the sail.
I disagree with the opinion that most speed sailors set their boom low. Looking at a few videos the boom is typically shoulder height and above. On a narrow speed board, that would seem higher than normal.
If your boom is slipping from chop bounces, you might want to spend some extra time making sure the clamp is set well.
|29th April 2010 03:43 PM|
|Farlo||Well I think that a cam sail has much less drag, possibly also less lift but better lift/drag ratio, than the equivalent no-cam. Although more powerful, it generates less sideways force. Of course it's difficult to prove because cam and no-cam sails often come in different designs. However there are a few exceptions and I wonder if a mag ever did this kind of test. But it has nothing to do with NS warranty anymore. Let's open another thread if you're interested.|
|28th April 2010 11:40 PM|
|28th April 2010 11:17 PM|
|Farlo||IMHO you can't really compare a race machine like the RAM and a freestyle sail, however good it is. This been said, the advantages of cams in such small sizes may be marginal, although competitors will always prefer the fastest sail. Also I presume that you can use smaller fins with cam sails. Would anybody confirm?|
|28th April 2010 07:49 PM|
|28th April 2010 07:28 PM|
|Farlo||Well, your boom is rather low in the window but this is frequent with North Sails, made for big guys. I have a pretty similar position whatever the wind speed. It's difficult to see from a few pictures whether the mast bends properly of not (the last one looks strange actually). Anyway small differences in bend curves may hardly be noticeable but translate in significant overstress. If you want to keep your RAM F8, my advice would be to get the closest compatible mast you can find. 60 to 75% carbon should be OK in this size.|
|28th April 2010 05:08 PM|
I have a theory also that lowering the boom helps in overpowered conditions not just because of a lower body position and easier mast foot pressure, but also because with a lower boom there is more of the mast above the boom clamp (which is a pivot point) and therefore the mast can more easily bend off and exhaust gusts as the sail creates greater leverage over the pivot point.
I got a couple of photos of my overpowered session and my mast is definitely bending nicely.
|28th April 2010 12:17 AM|
Excellent... but check your mast compatibility anyway. RDM have different bend curves than SDM, much more in the bottom I think. You will keep your sail longer, and get more from it, with the proper mast (not necessarily a North). Your loft should be able to advise you.
Feeling sluggish and slow to plane is not uncommon in strong winds. Sometimes you can hardly sheet in and your board seems stuck upwind. Additionally, low speed suggests that your sail was maybe too flat (too much outhaul). I don't think it has anything to do with your boom. Raising it may help in moderate wind but many sailors would lower it in high wind anyway.
|27th April 2010 11:30 PM|
I think that last time I sailed my sail/board wasn't planing fast because my boom had slipped down about 10cm during my overpowered session off shore, thus leading my whole setup to feel sluggish and slow to planing.
I only managed a peak of 21knots on the GPS, which was pretty disappointing but the chop was the hardest I've ever sailed in in Hong Kong so far...
Hopefully I'll get a more docile/flatwater session in soon enough (and my sail fixed by then!) where I can really push my Vmax and test the board's feeling with different boom heights.
|This thread has more than 10 replies. Click here to review the whole thread.|