So here I was musing “what would happen if I removed the battens from Arwen’s mainsail?”
Well not being the most technically alert sailor, I honestly had no idea. I know the mainsail can be a pain to drop and stow without the battens having a life of their own....but exactly how crucial are they?
Well, only one bunch of guys to ask really.......and so over to the JW forum I went.
Had to remind myself which part of the sail the leech was (pitiful isn’t it – sorry guys!)
(Unless you are an idiot like me – then it can be easily complicated).
Wow! Hack at the battens........I’m a tea totaller but that sounds like seriously straying into ‘have a double scotch before embarking on that course of action to stiffen the spine’ kind of territory! However........it did come from JW himself....so that’s OK with me. But hang on.....a vague memory is appearing. I'm sure Chris jeckells decided to do that unilaterally when he mad eup the sails............I think!
Hang on – head and clew, where is my ‘dinghy sailing for dummies’ book?
Ha, a good observation!
Generous offer – thank you!
Now see – here is someone who understands me completely – that is exactly what I want and can’t seem to get!
Now this is a person who knows a thing or two about design and how to sail – so I’m supposed to be getting a spitfire wing shape to the mainsail.........ah........now that is something to aim for!
Yeah – I think that’s a great idea but is probably, in all truth, beyond my technical ability, patience or understanding. It's spooky how well these guys know me!
Robin, Rob, Hajo, Joel, Alan and JW........thank you and sorry for asking such a dumb question in the first place! On the other hand, as I always say to my students...there is never anything like a dumb question.......if you don’t know, you don’t know and that’s the fun in learning....finding it out!
Steve
Dear Lord have mercy: wot is this man trying to do to that mainsail?
Well not being the most technically alert sailor, I honestly had no idea. I know the mainsail can be a pain to drop and stow without the battens having a life of their own....but exactly how crucial are they?
Well, only one bunch of guys to ask really.......and so over to the JW forum I went.
“I would try it and see. Your biggest problem might be the leach will fall off and you will lose power as your effective sail area is reduced”
Had to remind myself which part of the sail the leech was (pitiful isn’t it – sorry guys!)
“Theoretically better performance in light air; less control. Shouldn't be hard to try out...”
(Unless you are an idiot like me – then it can be easily complicated).
“Steve, there has been an update in the rig plan for Navigator, the top battens have been shortened at the forward end to make the sail easier to stow, take 120mm off forward end of the top one, and 200mm off the next one down. You should be able to hand stitch the ends of the batten pockets to do that, and it’s not a problem to shorten the batten itself with a hacksaw and file”.
Don't bother asking: it didn't work...hardly surprising really!
The word 'shambolic' is the politest I can use here
“I tried removing them all once just to see what would happen. Didn't work. The sail folds and flops over along a line from head to clew”.
Hang on – head and clew, where is my ‘dinghy sailing for dummies’ book?
“I think the reason your sail only bulges a bit when stowed is because your batten pockets are set at more of a vertical angle than mine. Mine are set more horizontally. Consequently, I have to pull my battens about half way out of the pockets every time I furl, which I want to avoid. Otherwise they're in my face or at a risk of snapping in half. Longer battens are generally better for sail shape, so since yours is working I'd be hesitant to mess with it too”.
Ha, a good observation!
“Next time I'm out I plan on trying John's shortened batten suggestion, and experiment with other lengths, and I'll report back with the results. Looking over my Navigator photo collection, I'm encouraged to see many mainsails without any full length battens at all, and they have beautiful sail shapes too”.
Generous offer – thank you!
“My goal is to "have my cake and eat it too". I want to keep that beautiful sail shape but also be able to drop the main right into my lazyjacks without having to touch the battens or anything else on the sail and without leaving my seat”.
Now see – here is someone who understands me completely – that is exactly what I want and can’t seem to get!
“My full length battens do bulge a bit when stowed on the boom, and I'll consider shortening as John has suggested, but I just want to say how pleased I am with my Duckworks sails, and how much pleasure that main sail has given me, both in performance and appearance. My youngest son often says (as he lays back in the cockpit looking upwards) that the shape of the main reminds him of the shape of Spitfire fighter wing. And the battens as originally designed give beautiful sail shape whatever wind there is (or not). So I hesitate to change a thing”
Now this is a person who knows a thing or two about design and how to sail – so I’m supposed to be getting a spitfire wing shape to the mainsail.........ah........now that is something to aim for!
“I think it was Kevin (navigator Slipjig) who had the clever idea of tensioning the yard luff with a short line though a cleat at the yard peak. When the sail is dropped the tension can be removed and the battens can lie more easily. It is a two-step process though so would not suit you”
stupid fixed grin says it all really
Not the brightest card in the pack!
Robin, Rob, Hajo, Joel, Alan and JW........thank you and sorry for asking such a dumb question in the first place! On the other hand, as I always say to my students...there is never anything like a dumb question.......if you don’t know, you don’t know and that’s the fun in learning....finding it out!
Steve
Bear in mind that all of the discussion about shortening full length battens and bulges when furling only applies to the gaff-rigged sail. The gaff rigged sail uses full length battens. Your lug sail does not, so at least you get to avoid that problem!
ReplyDelete-Joel
true
ReplyDeleteit's lazy jacks i need to sort
Steve,
ReplyDeleteHave you thought about converting your main to a gaff rig? You could do this by adding jaws on your gaff and shortening your boom and adding a gooseneck fitting, and a boom vang and throat halyard. You can keep your sail. It's been done before on other Navigators. You would get better performance and could easily add a topping lift and lazyjacks. I can help.
-Joel
Hi Joel. Been away abroad for a few days so sorry about delay. i need to think about this a bit. it is an appealing idea but i actually quite like the sprit boom rig as well. thank you for offer of help. I may well take you up on the offer - let me mull on this for a couple of weeks first.
ReplyDeletesteve
Steve, is your sail cut to the standing lugsail plan (sheet 7) or the gaffer plan (sheet 12)? The gaff sail is longer in the luff than the lugsail, similarly the gaffer mast length is longer than for the lug sail. I've always wondered why your yard does not stand more vertical - hence the question. Cheers, Alan H.
ReplyDeletealan - a really good question to which the answer is I'm not sure and will have to go and dig out the plans from the basement. I think its lug sail and smaller mast; in which case can you explain the bit about the yard not standing more vertically to me? steve
ReplyDeleteI am assuming your yard is not standing as vertically as it should - perhaps I am wrong? Basically it is all geometry. Forget the sail for a moment. In your imagination hoist the yard up the mast with no sail. The 'bow' end will point straight up. Now pull down on the bow end with a line attached to the bow end. The yard will stand up, and the 'verticalness' will be determined by how hard you are pulling, and how close to the mast base the pull is coming from. The cut of the sail will limit how vertical the yard can go. The head of the lug sail is set back 280mm from the lower luff, so by pulling on the downhaul next to the mast the yard cannot go vertical. But depending on where on the yard the halyard is attached the verticalness can be adjusted, within limits. ( move the halyard forward on the yard and verticalness decreases, move it back and it increases). One of the differences between the gaff and lug sails is that the gaff sail head is offset by 500mm, which is much greater than the 280mm offset for the lug. So if JW's gaff sail design is used in a standing lug configuration the yard cannot be set as vertically as it should be. (My previous post was in error - the lug luff is longer, not shorter, than the gaffer). So assuming the correct sail, and no boom tension for the moment, in practice the setting of the yard will be governed by the amount of downhaul tension, position of the halyard on the yard, and how close to the mast the downhaul is being applied. Like you I like the idea of the sprite boom - it is self-vanging, mainsheet to the stern of the boat and the boom is higher - hopefully saving my head from most of the inevitable bumps. How tall is your mast? Pity we cannot discuss this over a Wet.
ReplyDeleteactually everything you said makes sense to me - which is quite an achievement so well done! i think i need to look at a) where I tie on the main halyard to the upper yard - I may well have it too far forward on the yard and so could gain some extra verticalness from that; b) downhaul tension is pretty good in Arwen - however, there is always a however(!), the lower luff of the sail sits away from the mast base because of the slightly raised coaming and so there is a gap between lower luff and mastr - I use parrel beads to bring it in a little but this does slightly affect the downhaul tension....so here is another area I can take a closer look at
ReplyDeletewhen I've fiddled with tying the yard on higher up it has had the effect of lowering the sprit boom height and so you end up ducking left right and centre.
the mast height is right (just)....so I think the issue must be the yard tie on point and the gap down at sail luff base
really help comments and thank you for giving the time to help me out. much appreciated
steve
No worries!! I have been watching the posts about sail trim as I build, thinking about how I will set about getting things right. The parrells are obviously very important, and a bit tricky, for stopping the sail plan distorting, and preventing it moving aft, under outhaul tension to the boom.
ReplyDeleteI read an interesting post recently suggesting lacing the sail to the yard but initially leaving the yard luff tension loose. Hoist the sail and get the yard orientation how you want it, and take note of how much you have to tighten the yard luff, and then make that adjustment permanent. The idea was that if the yard luff was tight before the sail was raised, when downhaul tension is applied, some of the tension (which should be causing the yard to stand up) could be directed through the yard luff sail material to the peak, tending to stop the sail peak from rising, thereby causing a conflict. I will be definitely be paying attention to that.
Interesting that the boom drops when you adjust the halyard position. I notice that the batten positions are different on your sail from what are on my plans.
It is interesting though, isn't it? It's part of what I like about sailing - things to ponder over and understand and make work - totally different mind-space from power boating!
Cheers,
Alan H.
I'm becoming paranoid. Did I send the right sail plan to the sail makers? have I got old plans?
ReplyDeletelots to check over next weekend or so
Steve