|Topic Review (Newest First)|
|04-25-2011 06:40 AM|
Originally Posted by WDSchock View Post
Since our boat was originally designed to have a furling main, I suspect the 135 genoa (you can fly a 150 as well), was designed to do most of the work. It certainly does. In fact, deep downwind, we are often tempted to reef or entirely furl the main just to get it out of the way. We are very pleased with performance overall and mainsail shape is not usually a concern.
|04-24-2011 08:35 PM|
In mast furlers are a disaster, how does one control the mainsail shape if one can not change the Pre bend of the mast.....
Open up the leech ?
Tighten up the forestry ?
They also tend to have massive sections which eliminates 20-30% of the mainsail from having effective laminar flow.
|03-29-2011 12:46 PM|
|Iolanthesf||A thought regarding weight aloft: Permanent weight aloft will slow roll due to inertia at the masthead, but will also cause more heeling. If you really want it in a particular situation, it is easy to hoist a weight aloft. Another alternative would be to put a section of PVC pipe inside the mast at the top, and provide to pump water aloft when needed. This would be aerodynamically clean, lightweight when not needed, and much more socially acceptable than hoisting a nervous passenger up the mast in a storm.|
|01-26-2011 08:58 PM|
It is my understanding that you roll in what you need to "flatten" and "reduce" the sail for the conditions. I think the comparison to slab reef points doesn't really work as this system is variable - set what you need.
I suspect that these systems are not targeted at the "purist" sailor which equates to a tiny minority of the sailing population. Some of these roller furler mains are getting some really good reviews on their upwind and overall performance and speeds that work for me. Couple that with ease of use and it's pretty attractive for most sailors.
|01-26-2011 06:47 PM|
I took my sailing lessons on boats with conventional mains, but purchased a 34' Tartan with in mast furling.
We have made two offshore trips and on one encountered significant storm. For a newbie I would have been very nervous trying to reef the main in those conditions, as the squall came up quickly. Howerver with the in mast furler, the sail was brought in within seconds without leaving the cockpit.
Also for me in learning I can change the amount of main up very easily by myself and experiment in different levels of wind. I doubt I would do that with a conventional reefing system (just too lazy)
I am sure there are compromises as there is less sail and no battens, but the advantages at this point in my skill set seem to outway the disadvantages.
I have yet to have any problem with furling or unfurling, but the boat is rel new (2006)
|01-26-2011 02:10 PM|
|sailingdog||Nicely said Rich.|
|01-26-2011 11:58 AM|
There's a 'functional' problem with in-mast furlers as most discussions of the in-mast 'furlers' only dwell on the 'mechanicals' ... and there is a vastly more important consideration - SAIL SHAPE. The following will hopefully explain why in-mast reefing is of very LOW BENEFIT, (beyond 'ease of use' and disregarding entirely the reliability, etc. issues of the 'hardware') in controlling the all important sail SHAPE: ...
Sails are not 'flat sheets of cloth', they are quasi-spherical 3 dimensional shapes ... for a damn good reason: aerodynamics. Just about any sail has most of its camber or position of max. draft (POMD) at somewhere near mid-cord of the full-up sail; the 'approach or entry shapes' to the POMD will usually be found to begin @~15-20% of cord length. Most sails that are roller reefed are left FLAT, essentially NO GOOD for 'aerodynamic flow' and typically when beyond 30% 'roll-up' are no longer or greatly reduced 'aerodynamic shapes' .... and simply cannot be used effectively when beyond the 30% 'roll-up'.
Plus, when in conditions that require one to reef you usually (when in non-FLAT water) need a 'full drafted' sail for the POWER it supplies for punching into waves and steep chop; when roller reefing (beyond ~30%) all you're going to get is a distorted FLAT (the panel shape aft of the mid-cord is ~'FLAT') and that 'flatness' is for SPEED SAILING in FLAT WATER and definitely NOT the 'shape' you want for *PUNCHING THROUGH" and over waves and steep chop. If you roller-reef beyond that ~30% then all you're going to have aloft is something akin to an NON-aerodynamic 'flat sheet of plywood --- something with very much LESS than the 3 dimensional shape of a 'sail', although it may 'look like' a sail because its 'triangular'.
With a roller boom or slab reefed sail you can always 'move' the important POMB back and forth via halyard and/or cunningham tension .... try that with a in-mast furler and you will JAM the furler and without any change in POMD because it can be thus trapped deep within the 'roll' !!!!! therefore NO change in the POMB fore/aft location. With inmast roller reefing, you can adjust the outhaul until you have a spinnaker like shape or a flat as a sheet of plywood shape .... but NOTHING that you can do with an in-mast roller furler-reefer will change the position of the POMB!!!!!!!!!!! (the position of the POMB is the functional item that has the GREATEST effect on 'balancing the helm pressure' and much more effect than the amount of sail area exposed !!!!!!!!!!!!!!!!!)
Roller BOOM reefing, or better - slab reefing, will keep the POMD where it belongs, AND, you can power-up or power-down by changing the luff tension (via halyard or cunningham strain), etc. to change the location of Point of Max. Draft POMD to where its 'most effective' for the present wind and seastate conditions .... and can do this POMD relocation when single reefed, double reefed or 'deeper'.
So, If your cruising plans include venues wherein you might possibly be beating instead of ~100% of the time 'going downhill', then that FUNCTIONAL REQUIREMENT to have an aerodynamic shape aloft in high wind range conditions would almost entirely, ... or should, EXCLUDE an in-mast furler.
If however your intended venue is only for 'moderate' conditions that almost all of the time will only need a maximum 'single reef', then in-mast furling/reefing will be 'fine' .... (and with NO comments about 'reliability').
My emphasis here is SAFETY, not 'performance' as if you cant 'point' when you 'really NEED' to ... you're now vulnerable and 'dangerous'.
|01-26-2011 09:36 AM|
One point. A double line reefing system is actually a lot better in terms of being able to control sail shape. This is especially the case as the sails get larger. With a single line system you can not control the tension on the foot of the sail as well and can't control the sail shape as easily as you can with a double line system.
Originally Posted by robfox View Post
|01-25-2011 09:13 PM|
In Mast furler
Once again I have learned a lot from reading a sailnet thread.
I am fortunate that we bought our present 37 foot yacht set up with Harkan Batcars & a very good single line reefing system for the main.It enables me to put in reefs without leaving the cockpit and at any point of sail.
Just before Christmas we were on a 60 mile coastal sail when our forecast 15 knots (on a broad reach) went to 30knots and gusted up to 40 knots.I put 3 reefs in without drama while my wife steered downwind.A couple of rolls in the headsail and comfortable sailing at up to 8.5 knots.
We are looking for our next yacht which will be bigger and many of those available have in mast furling.
What I have learned from this forum has reinforced my previous views that, for me,single line reefing is essential. It also rules out any yacht that has in mast furling because of the cost to change over.
This is a personal decision of mine and no reflection of anyone elses choice.
Thanks again for your contributions and advice.
|01-23-2011 10:54 AM|
Originally Posted by bosn181 View Post
I recently moved to a boat with a furling main. I do miss the sail shape of even the old, blown out main on my last boat. I love the convenience and we sail more than we used to. For how I use the boat, and where we sail, in-mast furling is wonderful. If I lived elsewhere, raced again, did blue-water cruising, I would not only use a different system but would have a different boat.
I'm sold on in-mast and will never go back unless there is a better solution for my needs developed.
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