Page 1 of 2 12 LastLast
Results 1 to 35 of 49

Thread: Sailing rig recommendation for this small boat?

  1. #1
    Join Date
    Nov 2014
    Location
    Kaunas, Lithuania
    Posts
    71

    Default Sailing rig recommendation for this small boat?

    Hello, guys, it's me again. Me and my little boat Melatelia, enduring a headache in preparations for the new sailing season once more. For those unaware, she's a 10' 7" pure sailer (no oars, except for emergency sculling), 48" on the beam, ultra light 3/16" ply stitch&glue construction - hull weights 66lbs, light enough to car-top single handed without any gear. There's no trailer, she's always car-topped. Off-season, she's stored in a small, cramped garage (workshop). Her current rig is my home-sewn balanced lug. 83 square feet, giving her a SA/D ratio of 30 when sailed single-handed (extra displacement allows for one passenger of female gender). All spars are made from pine, rectangular section, yard and boom are solid, 1.6"x2", both 118" long, tapered to 80% on the ends. Mast is hollow box section, 2.5" diameter, 0.6" walls, 158" long, tapered to 80% at the top. Here's a screenshot from my CAD program, and several photos from the latest regatta:



    Though she wasn't designed a racer, the performance is superb, competitive with Lasers, 420's, 470's, even multihulls in light air. That part is pretty amazing for a $500 home-made. The problem is weight aloft. Rig is so incredibly heavy, that it feels like balancing a unicycle on a circus rope. If the boat capsizes, it is barely possible to right her back up by stepping on the daggerboard - the leverage of the rig is just too much. Even with the massive side flotation tanks, the cockpit is full of water afterwards. As much as I love the simplicity of the lug, the weight aloft makes it all very impractical. Also, storing that 157" mast is a constant headache. It can barely fit in my garage, and there's nowhere else to put it.

    I am wondering if there is any alternative rig that I could use on the boat. The list of requirements is as follows:
    1. At least 80 square feet of area (now, I know, I know, you'll say it's way too much for a boat this small, but believe me, 95% of the time, it is still undercanvased - in my country, winds are very light... Except when a sudden storm comes without a warning, so the rig must be sturdy enough too);
    2. At least 3% lead - that is the lead on my lug sail, and I can tell it's borderline. Any less, and the weather helm will be too much.
    3. No spar can exceed 157" - but frankly, I'd be much happier of all spars fit inside the boat - that puts the limit at 118". I can build joints if needed, but I'd like to avoid it on the mast (frankly, I REALLY want to re-use my current mast by shortening it... My budget isn't exactly ready for another mast).
    4. Center of mass must be as low as possible. I can't stress this out enough.
    5. Boom can't be lower than 17" above mast partner - any lower, and the front passenger will be unable to duck under during tacks.
    6. Weatherliness... At least the same a lug can provide. I'm not asking more than that.
    7. Simplicity, simplicity, simplicity... This is a small boat, and I'd hate to spend more than 10 minutes rigging and un-rigging it each time... It would defeat the purpose.

    Now, there are plenty of traditional rigs that meet most of the criteria, but the problem is getting that 80ft^2 sail area without moving CE too far back. Thing is, CLR is just 31" aft of the mast. So, it means that some of the sail area must be in front of the mast if I ever hope to get that sail area without making a towering mast (which is, by definition, heavy). My limited knowledge tells me that I'm left with lug, junk, lateen, or multi-sail rig. Lug, as I figured out now, requires spars that are just too heavy. Junk rig would be pretty much the same, plus a ton more lines to deal with. I hoped that boomless lateen might be the answer, but after making another thread on this forum, I realized that the resulting rig would be just as heavy. So, by my reasoning, I'm left with some kind of sloop rig. The simplest I can think of is peak sprit with a jib, for example, like this:



    Sail area is 76 square feet, all spars are 118" long (I can re-use my current mast by shortening it), lead is 3%. I can up the sail area and move CE forward a bit if I use a 2-piece sprit pole. Center of mass is very low. Sprit sails are also said to be very weatherly, more so with the jib. The obvious downside is lack of simplicity. Handling two sails in a boat this small singlehanded might be a little over my capability, especially when launching and landing in foul weather.. Also, since the jib is boomless, it might create more weather helm than the mainsail, so maybe my 3% lead isn't enough... I don't know. This option doesn't fit all my requirements, but this is the closest I got on my own.

    For those still reading... I would like to ask, if I may, could someone consult me and help me to choose a rig that would fill all these requirements? I'm hoping that I'm missing some simple and obvious solution due to my lack of knowledge and experience. If you want to make a sketch or something, here's an "empty" boat with just a 118" mast, and CLR marker. The long dashed line is just vertical extension of CLR for easier visualization. Short dashed line marks the 5% lead position... Ideally, CE should end up there. I can't get it that much forward while retaining that 80 square feet figure, and by gods, I must have it!



    Thank you for your time... And I hope that the requirements I set for this rig aren't asking for the traditional addition of "does it have to circumnavigate too?"

  2. #2
    Join Date
    Aug 2006
    Location
    Rockford, IL
    Posts
    7,843

    Default Re: Sailing rig recommendation for this small boat?

    I didn't notice where you pointed out the problem with the present rig.

  3. #3
    Join Date
    Jun 2000
    Location
    Madison Wisconsin
    Posts
    8,296

    Default Re: Sailing rig recommendation for this small boat?

    I really think the first thing to do before trying to design a new rig is to throw out all the formulas and see how much excess weight aloft you can remove from this one. For example: The test yard and boom that I made for this lateen are 123" long, rectangular with the corners rounded off. At 45% aft they are 1.6" high by 1.5" wide. At the heel, they are 1.25" high by 1.2" wide, and at the peak 1.2" high and 1" wide.



    Both were cut from a single, carefully selected SPF (assorted spruce, pine or fir) 2 x 4 from Home Depot. These spars are actually plenty stiff enough to sail with and would weigh substantially less than your spars. I suspect that you could also take a fair bit off the upper mast diameter without losing any performance. With that much sail area on such a small hull, you will never likely have enough resistance to heeling for the mast to need to survive being plumb in gusts.



    If your sail's leech is cut properly, you should also be able to ditch the battens. A properly designed and slightly hollowed lugsail leech doesn't need battens. They're just excess weight.

  4. #4
    Join Date
    Mar 2009
    Posts
    527

    Default Re: Sailing rig recommendation for this small boat?

    She is 3 ft shorter and 6" narrower than a Laser, and has 10% more sail area. No wonder she goes well in light airs, tons of SA and no wetted surface.

    Cut her back to about 60 - 65 ft2, with a shorter mast, shorter boom, shorter yard. Lighten the yard as much as possible: use spruce instead of pine, shorter, make it thinner, give it less depth.

    Ok, maybe only cut her back to 70 ft2, if you are never going to see any wind. Try to take it off the top: shorter mast, yard, sail. If your winds are as light as you claim, you can reduce the dimensions of your spars.

  5. #5
    Join Date
    Nov 2014
    Location
    Kaunas, Lithuania
    Posts
    71

    Default Re: Sailing rig recommendation for this small boat?

    Quote Originally Posted by Nicholas Scheuer View Post
    I didn't notice where you pointed out the problem with the present rig.
    Too much weight aloft.

    Thank you for your reply, Todd. Thanks for the example too. But I am unsure, do I size the spars by their length, or by the sail area? If by length, what is the diameter-to-length ratio for attached edge yard, and loose-footed boom? The usual ratios are for round spars, but I can easily convert the figures to square section. If you could quote these ratios, I could estimate how much weight can I shave off from my spars.

    As for the mast, I used Skene's famous formula, diam. (in) = ∛(16*P*L*SF/(π*σ)), using 1.15 for wind pressure, and 1.5 for Safety Factor. But since his formula is for round, solid spars, I designed a square hollow one with the same stiffness. It came out to 2.5" diameter. I did a wild-ass guess that 80% taper at the top would be appropriate, since the luff isn't attached. As I said, walls are 0.6". If you think I overbuilt it, how much can I safely shave down?

    As for the leech, the hollow is 1/74 of the length - but without battens, it still tends to curl. I made dead sure that the weave runs parallel to the leech, so I'm not sure what's the cause for it. I guess sub-standard fabric?

  6. #6
    Join Date
    Nov 2014
    Location
    Kaunas, Lithuania
    Posts
    71

    Default Re: Sailing rig recommendation for this small boat?

    Quote Originally Posted by robm View Post
    She is 3 ft shorter and 6" narrower than a Laser, and has 10% more sail area. No wonder she goes well in light airs, tons of SA and no wetted surface.

    Cut her back to about 60 - 65 ft2, with a shorter mast, shorter boom, shorter yard. Lighten the yard as much as possible: use spruce instead of pine, shorter, make it thinner, give it less depth.

    Ok, maybe only cut her back to 70 ft2, if you are never going to see any wind. Try to take it off the top: shorter mast, yard, sail. If your winds are as light as you claim, you can reduce the dimensions of your spars.
    Thanks, I considered that option, but that would throw me out of competition with other boats... And I just can't let that happen! 80ft^2 is as low as I'm willing to go. Wish I could use spruce, but the spruce we have around here is always full of knots. Impossible to get clear sections that long. I could make box-section yard to save some weight aloft, though.

  7. #7
    Join Date
    Mar 2009
    Posts
    527

    Default Re: Sailing rig recommendation for this small boat?

    The box section would add windage. Stiff spars are not what you want. Bendy ones make it possible to keep your big rig when the winds blow, if they bend the right way.

  8. #8
    Join Date
    Dec 2003
    Location
    Portland, Oregon
    Posts
    38,261

    Default Re: Sailing rig recommendation for this small boat?

    Hard to tell from just fotos, but what weight is the sailcloth? It looks stiff. I wonder if the weight is more than it needs to be, of if the apparent stiffness is simply from a cloth with LOTS of resin?

    I agree that both your mast and esp. your yard may be a bit stout. This is an area where it pays to shave ounces.

    I have no problem with being over-canvassed. My smallest boat, an 8' PDR, carries 87 sq. ft. Being over-canvassed is what carried me to a 4th place finish in the world championship event, despite it being and brand new boat, and being tangled/fouled at the start line.

    Michael Storer is a bit of a whiz when it comes to small rigs - esp. the balanced lug. I suggest you dig into his site, and check out his sail loft - RSS. I think you'll find you have gone stouter on the spars than is optimum. http://www.storerboatplans.com/wp/?s=balanced+lug
    David G
    Harbor Woodworks
    http://www.harborwoodworking.com/boat.html

    "It was a Sunday morning and Goddard gave thanks that there were still places where one could worship in temples not made by human hands." -- L. F. Herreshoff (The Compleat Cruiser)

  9. #9
    Join Date
    Nov 2014
    Location
    Kaunas, Lithuania
    Posts
    71

    Default Re: Sailing rig recommendation for this small boat?

    Quote Originally Posted by robm View Post
    The box section would add windage. Stiff spars are not what you want. Bendy ones make it possible to keep your big rig when the winds blow, if they bend the right way.
    I believe you... Trouble is, finding that sweet point of a spar that bends well, yet doesn't break too easily When you said box section would add windage, did you mean to suggest I should make a round yard this time?

  10. #10
    Join Date
    Mar 2009
    Posts
    527

    Default Re: Sailing rig recommendation for this small boat?

    No, I was thinking you wanted to build a hollow box spar. Same amount of wood, with a hole in the middle to make it stiffer, just like your mast.

    Keep your oars handy, in case of breakage.

  11. #11
    Join Date
    Nov 2014
    Location
    Kaunas, Lithuania
    Posts
    71

    Default Re: Sailing rig recommendation for this small boat?

    Quote Originally Posted by robm View Post
    No, I was thinking you wanted to build a hollow box spar. Same amount of wood, with a hole in the middle to make it stiffer, just like your mast.

    Keep your oars handy, in case of breakage.
    It is currently square solid. I wanted to make square hollow. Not even square, but more like rectangular. It would have to be slightly bigger, so yes, more windage, but would it really be that bad when you consider weight savings?

  12. #12
    Join Date
    Nov 2014
    Location
    Kaunas, Lithuania
    Posts
    71

    Default Re: Sailing rig recommendation for this small boat?

    Quote Originally Posted by David G View Post
    Hard to tell from just fotos, but what weight is the sailcloth? It looks stiff. I wonder if the weight is more than it needs to be, of if the apparent stiffness is simply from a cloth with LOTS of resin?

    I agree that both your mast and esp. your yard may be a bit stout. This is an area where it pays to shave ounces.

    I have no problem with being over-canvassed. My smallest boat, an 8' PDR, carries 87 sq. ft. Being over-canvassed is what carried me to a 4th place finish in the world championship event, despite it being and brand new boat, and being tangled/fouled at the start line.

    Michael Storer is a bit of a whiz when it comes to small rigs - esp. the balanced lug. I suggest you dig into his site, and check out his sail loft - RSS. I think you'll find you have gone stouter on the spars than is optimum. http://www.storerboatplans.com/wp/?s=balanced+lug
    Cloth is 8.5oz... It is not exactly sailcloth, just resinated polyester. It's the only fabric that I can get around here except Dacron, and Dacron, well... For this size of a sail, it would cost twice as much as the rest of the boat

    Yes, now it's quite obvious that I overbuilt my yard. Not sure about the mast, though - according to Skene's formula, it is borderline stiff enough. Maybe you know what's the recommended yard diameter-length ratio?

    Oh, and thanks for the link. Now that I opened it, it seems I might find the answers there.

  13. #13
    Join Date
    Jun 2000
    Location
    Madison Wisconsin
    Posts
    8,296

    Default Re: Sailing rig recommendation for this small boat?

    Stiff spars are not what you want. Bendy ones make it possible to keep your big rig when the winds blow, if they bend the right way.
    This statement is either not true, or oversimplified to the point of being worthless - depending on how you want to look at it. Overly bendy spars on something like this lugsail would make it extremely difficult to design and cut a sail that will give decent performance in a variety of real world conditions. With every little puff the sail will change shape and the sailor will have no control over that shape. How do I know this? Maybe because I've been making sails since 1980, many of them lugsails. While there are certainly boats that use bendy masts to shape, power-up, or depower their sails, this ain't one of them.

    Laukejas, I think you're over-analyzing a couple of simple wooden spars. All you have to risk is the cost of a 2 x 4 to see how much lighter you can get your yard and boom. Get out a plane or a spokeshave and attack the current ones, or rough-cut a couple new blanks and start thinning them down to see how much lighter you can get them without them getting too whippy. You already have the boat and sail built to test them with and have virtually nothing to lose. Sticking an oversized and overly tall rig on a little dinghy is never going to be a perfect scenario all the time. You aren't going to calculate your way out of that, but you can certainly play around with different spars inexpensively and go out and learn things.

  14. #14
    Join Date
    Nov 2014
    Location
    Kaunas, Lithuania
    Posts
    71

    Default Re: Sailing rig recommendation for this small boat?

    Quote Originally Posted by Todd Bradshaw View Post
    This statement is either not true, or oversimplified to the point of being worthless - depending on how you want to look at it. Overly bendy spars on something like this lugsail would make it extremely difficult to design and cut a sail that will give decent performance in a variety of real world conditions. With every little puff the sail will change shape and the sailor will have no control over that shape. How do I know this? Maybe because I've been making sails since 1980, many of them lugsails. While there are certainly boats that use bendy masts to shape, power-up, or depower their sails, this ain't one of them.

    Laukejas, I think you're over-analyzing a couple of simple wooden spars. All you have to risk is the cost of a 2 x 4 to see how much lighter you can get your yard and boom. Get out a plane or a spokeshave and attack the current ones, or rough-cut a couple new blanks and start thinning them down to see how much lighter you can get them without them getting too whippy. You already have the boat and sail built to test them with and have virtually nothing to lose. Sticking an oversized and overly tall rig on a little dinghy is never going to be a perfect scenario all the time. You aren't going to calculate your way out of that, but you can certainly play around with different spars inexpensively and go out and learn things.
    Well... Thing is, in my country, it takes at weeks to source such a simple thing as a straight, clear 2x4. Last time I needed timber for the spars you see in the photos, it took me nearly 2 months. Driving from lumberyard to lumberyard, going through piles, waiting in lines, and always hoping to be the first guy who gets to choose from the new batch. Most of our lumber is really bad - twisted, full of knots, barely acceptable for general construction work. I've been to USA. What you guys have in the hardware store next door, I couldn't get in my country even if I searched for a year. What we have in our hardware store wouldn't even pass for firewood. This is a third world country. I can get decent timber eventually (straight enough so that I can plane it straight, and no more than 1-2 large knots per foot), but it takes forever, and such "quality" timber costs around $1200 per cubic meter. So you can understand why I would want to rather spend a few more days with calculator, instead of spending weeks driving around lumberyards once I break something. And if I break my mast, well... That's the end of sailing season for me. There's no way I could get new timber in time, and frankly, with these prices, I probably wouldn't be able to afford to.

    Sorry to be so picky about this. I know all these numbers come to you naturally, from experience and educated guess. But I have neither. Instead of just copying similar designs, I'm trying to work out some way to calculate, even if roughly, to how close I am to safety margins... I'm trying to learn the how's and why's. Which is why I'm hoping you could perhaps quote some general length-diameter ratios - I can work my way from there.
    Last edited by Laukejas; 03-20-2017 at 07:48 PM.

  15. #15
    Join Date
    May 2012
    Location
    UK. Cornwall, Somerset, Ipswich.
    Posts
    2,792

    Default Re: Sailing rig recommendation for this small boat?

    Lukejas, shave your spars down to round, this will eliminate weight up there...costs nothing, no new wood to find. There's not much strength in the corners of the square spars anyway.

    The 'over-powered' sensation is because leverage is exponential; a small amount of sail/weight up high, heels the boat much much more than the same amount of sail/weight down low.

    You might consider a gunter rig after trimming your spars, if you still feel too heavy up there. Easier to stow in your garage too; smaller spars.

    Excellent English by the way, and good luck.

  16. #16
    Join Date
    Nov 2004
    Location
    Port Townsend WA
    Posts
    9,842

    Default Re: Sailing rig recommendation for this small boat?

    One, extremely efficient, rig is the spar and sail plan for the International Olympic Finn dinghy. The boats have a bendy mast that controls the draft in the single sail. This is a very high performance rig. The sail is held by a luff groove in the elliptical unstayed mast. The major axis of the ellipse is athwart ships to afford stiffness in that direction.
    Jay
    https://en.wikipedia.org/wiki/Finn_(dinghy)

  17. #17
    Join Date
    Jun 2000
    Location
    Madison Wisconsin
    Posts
    8,296

    Default Re: Sailing rig recommendation for this small boat?

    Lukejas, shave your spars down to round, this will eliminate weight up there...costs nothing, no new wood to find.
    Exactly my point. You already have spars and you already know that they are too heavy. The whole rig is simple enough that you can even plane off a bit, take them test sailing unfinished and see if you might want to plane off a bit more before refinishing them - and do it multiple times if needed.

    You are putting an oversized, experimental rig on a boat that was never designed to handle that much and thinking that you should be able to calculate your way out of the problem. That's a pretty tall order. My wife is from Latvia. She says that a very large percentage of the country is forested and better than half of that is pine and spruce. Perhaps you might try going "next door" in search of a couple of 2x4s.

  18. #18
    Join Date
    Jan 2005
    Location
    Deepest Darkest Wales
    Posts
    17,584

    Default Re: Sailing rig recommendation for this small boat?

    If you can find it, bamboo can make an excellent yard, comes ready-hollowed with a fine strength to weight ratio.
    Someday, I'm going to settle down and be a grumpy old man.

  19. #19
    Join Date
    Nov 2014
    Location
    Kaunas, Lithuania
    Posts
    71

    Default Re: Sailing rig recommendation for this small boat?

    Quote Originally Posted by P.I. Stazzer-Newt View Post
    If you can find it, bamboo can make an excellent yard, comes ready-hollowed with a fine strength to weight ratio.
    You're joking, right? I can't even get decent pine. Haven't seen bamboo here in my entire life here (and I searched, I'd love to use it for a spar).

    Quote Originally Posted by lupussonic View Post
    Lukejas, shave your spars down to round, this will eliminate weight up there...costs nothing, no new wood to find. There's not much strength in the corners of the square spars anyway.

    The 'over-powered' sensation is because leverage is exponential; a small amount of sail/weight up high, heels the boat much much more than the same amount of sail/weight down low.

    You might consider a gunter rig after trimming your spars, if you still feel too heavy up there. Easier to stow in your garage too; smaller spars.

    Excellent English by the way, and good luck.
    Quote Originally Posted by Todd Bradshaw View Post
    Exactly my point. You already have spars and you already know that they are too heavy. The whole rig is simple enough that you can even plane off a bit, take them test sailing unfinished and see if you might want to plane off a bit more before refinishing them - and do it multiple times if needed.

    You are putting an oversized, experimental rig on a boat that was never designed to handle that much and thinking that you should be able to calculate your way out of the problem. That's a pretty tall order. My wife is from Latvia. She says that a very large percentage of the country is forested and better than half of that is pine and spruce. Perhaps you might try going "next door" in search of a couple of 2x4s.
    Alright, thank you, that's what I'll do. My workshop is about 120 miles away from the venue where I sail, so I'm afraid I'm pretty much locked in with whatever spar choices I make at the start of the season. Then again, I suppose I can take a hand plane and a bucket of varnish with me... I'll see what can be done. Todd, for starters, I'll try to make my yard and boom of similar stiffness as the lateen spars that you shown earlier. I'll remove some width and round the corners on the spar until it comes to similar stiffness. If that will prove to be too stiff, I'll thin it down more.

    One last question, if I may... Considering my yard, even when rounded, will be narrow and tall oval (something like 1x2", it should be very weight-efficient), is there some smart way of attaching the halyard that ensures the yard will always "stand" on the long edge? Since it will be much more bendy on the other axis, it might want to "fall" onto it's side, and then bend excessively or even break. Usually, I use just clove/constrictor knot, but the oval spar might slip and start rotating under the knot. I could, of course, just drill a hole, and epoxy in an eye-bolt to make an attachment point for the halyard, but a hole might compromise the strength of the yard in that particular point. Is there some other way to make sure that such a spar will keep it's correct orientation?

  20. #20
    Join Date
    Mar 2014
    Location
    Hasslö, Blekinge, Sweden
    Posts
    358

    Default Re: Sailing rig recommendation for this small boat?

    I think the ovalness will be a problem no matter how you try to handle it, a through bolt will weaken it quite a bit, and will probably not help all that much. I'd go with a round spar for this rig.

    /Mats
    My blog about my time as a boat building student and as a rigger apprentice http://kaptenmohsart.blogspot.se/ in Swedish only, but there are many pictures :-)

  21. #21
    Join Date
    Nov 2014
    Location
    Kaunas, Lithuania
    Posts
    71

    Default Re: Sailing rig recommendation for this small boat?

    Quote Originally Posted by mohsart View Post
    I think the ovalness will be a problem no matter how you try to handle it, a through bolt will weaken it quite a bit, and will probably not help all that much. I'd go with a round spar for this rig.

    /Mats
    Round shape is very inefficient in terms of stiffness-per-weight... With oval, I might reduce the weight of my current yard by ~41%. With round, the best weight saving I could do is ~23%. That's nearly an extra pound in the most elevated portion of the rig...

  22. #22
    Join Date
    Jun 2000
    Location
    Madison Wisconsin
    Posts
    8,296

    Default Re: Sailing rig recommendation for this small boat?

    Yes........ but if it can't be made to work that way (which it very well may not be) - what the hell good is it????? All the calculating in the world isn't worth squat if the calculated product can't do the job properly!

  23. #23
    Join Date
    Nov 2014
    Location
    Kaunas, Lithuania
    Posts
    71

    Default Re: Sailing rig recommendation for this small boat?

    Quote Originally Posted by Todd Bradshaw View Post
    Yes........ but if it can't be made to work that way (which it very well may not be) - what the hell good is it????? All the calculating in the world isn't worth squat if the calculated product can't do the job properly!
    So, you also mean to say that there's no way to attach the halyard in a way that would make the yard stand on it's long edge? :/ Because if so, then there's very little weight I can shave off my yard... At least if I'm aiming for a similar stiffness as your lateen sail spars.
    Last edited by Laukejas; 03-21-2017 at 01:06 PM.

  24. #24
    Join Date
    Jun 2000
    Location
    Madison Wisconsin
    Posts
    8,296

    Default Re: Sailing rig recommendation for this small boat?

    So, you also mean to say that there's no way to attach the halyard in a way that would make the yard stand on it's long edge?
    The only spars I can think of where you can stand them on edge and be sure they stay that way are held in that position by a gooseneck or jaws - which aren't available in this case.

    My advice is to put down the calculator and slowly back away. Stop making excuses for everything and go find the nearest plane or spokeshave. Look at the boom in your close up photo above. That thing is a beast, and the yard would appear to be similar from what we can see. In an hour out in the driveway or back yard they could both be planed down a bit, tapered on all sides toward their ends and actually start looking like real spars. I'd bet that you could get them both down to around 1.2" square on the heels and 1" square at the peak ends and still have adequate stiffness. As I mentioned above, they could even be tested on the water unfinished if you want to do the job in stages. With indoor storage on non-sailing days, they could probably get by just fine that way for a couple of seasons without deteriorating. You can varnish them once they are done slimming down. Stop worrying about percentages of weight reduction and similar, as any improvement is better than what you have now.

  25. #25
    Join Date
    Nov 2014
    Location
    Kaunas, Lithuania
    Posts
    71

    Default Re: Sailing rig recommendation for this small boat?

    Quote Originally Posted by Todd Bradshaw View Post
    The only spars I can think of where you can stand them on edge and be sure they stay that way are held in that position by a gooseneck or jaws - which aren't available in this case.

    My advice is to put down the calculator and slowly back away. Stop making excuses for everything and go find the nearest plane or spokeshave. Look at the boom in your close up photo above. That thing is a beast, and the yard would appear to be similar from what we can see. In an hour out in the driveway or back yard they could both be planed down a bit, tapered on all sides toward their ends and actually start looking like real spars. I'd bet that you could get them both down to around 1.2" square on the heels and 1" square at the peak ends and still have adequate stiffness. As I mentioned above, they could even be tested on the water unfinished if you want to do the job in stages. With indoor storage on non-sailing days, they could probably get by just fine that way for a couple of seasons without deteriorating. You can varnish them once they are done slimming down. Stop worrying about percentages of weight reduction and similar, as any improvement is better than what you have now.
    All right... I will do that. Thank you very much for your advice, time and patience. I know it takes quite a bit of the latter

  26. #26
    Join Date
    Mar 2014
    Location
    Hasslö, Blekinge, Sweden
    Posts
    358

    Default Re: Sailing rig recommendation for this small boat?

    Apart from the spar issues, since you have a boom you could replace it with a longer one and thus make the sail wider and be able to have it shorter and still keep the area desired. You can also remove the battens as was suggested, or keep them and make a sail that has a convex leech; that would also increase the area and make it possible to cut down on the height.
    Another option is to remove the boom, while it is low it's weight still makes a difference, and I believe that it is easier to duck under a boomless sail so you may be able to have the sail set a bit lower that way (though for sheeting reasons, this may not work out for you).
    You could also add shrouds to help support a thinner mast.

    /Mats
    My blog about my time as a boat building student and as a rigger apprentice http://kaptenmohsart.blogspot.se/ in Swedish only, but there are many pictures :-)

  27. #27
    Join Date
    Mar 2014
    Location
    Hasslö, Blekinge, Sweden
    Posts
    358

    Default Re: Sailing rig recommendation for this small boat?

    One thing about the above: Keeping the area of the sail isn't everything, since the wind is always stronger up above, to keep the performance you will probably need to increase the area if you lower the CE.

    /Mats
    My blog about my time as a boat building student and as a rigger apprentice http://kaptenmohsart.blogspot.se/ in Swedish only, but there are many pictures :-)

  28. #28
    Join Date
    Nov 2014
    Location
    Kaunas, Lithuania
    Posts
    71

    Default Re: Sailing rig recommendation for this small boat?

    Quote Originally Posted by mohsart View Post
    Apart from the spar issues, since you have a boom you could replace it with a longer one and thus make the sail wider and be able to have it shorter and still keep the area desired. You can also remove the battens as was suggested, or keep them and make a sail that has a convex leech; that would also increase the area and make it possible to cut down on the height.
    Another option is to remove the boom, while it is low it's weight still makes a difference, and I believe that it is easier to duck under a boomless sail so you may be able to have the sail set a bit lower that way (though for sheeting reasons, this may not work out for you).
    You could also add shrouds to help support a thinner mast.

    /Mats
    Thank you, that is a sound advice. But I'm afraid I cannot make my boom any longer, because then the rig won't fit inside the boat for transportation. Since I car-top my boat, it would be a huge issue. I designed this rig so that only the mast has to be carried externally. The rest fits inside the boat. Like this:



    Sail area is quite enough now. I considered making a convex leech, but I don't trust in this fabric enough to keep the leech from fluttering, even with battens. See, currently, the leech is concave, with 1/74 ratio, as recommended in the Sailmaker's Apprentice book. Still, even with that concave the leech does weird things without battens. I suppose I could re-cut the leech and make that concave deeper - but even then, I'm not sure if it will work without battens.

    As for shrouds, well, they create a lot of downforce on the mast. The bottom of this boat is 3/16" (4mm) plywood. I'm afraid the mast would drive itself right through the bottom. And anyway, setting up shrouds each time isn't exactly the definition of simplicity and practicality...

    Anyway, good advice. I'll keep it in mind for my next boat. Thanks.

  29. #29
    Join Date
    Sep 2011
    Posts
    425

    Default Re: Sailing rig recommendation for this small boat?

    Sunfish practice sails are about the cheapest built sail you can get. Two sizes I believe the larger are 75 sq ft. Lateen so you'd get smaller spars. No idea how hard it is to get a sail from the usual places to where you are.
    Quote Originally Posted by Laukejas View Post
    Thank you, that is a sound advice. But I'm afraid I cannot make my boom any longer, because then the rig won't fit inside the boat for transportation. Since I car-top my boat, it would be a huge issue. I designed this rig so that only the mast has to be carried externally. The rest fits inside the boat. Like this:



    Sail area is quite enough now. I considered making a convex leech, but I don't trust in this fabric enough to keep the leech from fluttering, even with battens. See, currently, the leech is concave, with 1/74 ratio, as recommended in the Sailmaker's Apprentice book. Still, even with that concave the leech does weird things without battens. I suppose I could re-cut the leech and make that concave deeper - but even then, I'm not sure if it will work without battens.

    As for shrouds, well, they create a lot of downforce on the mast. The bottom of this boat is 3/16" (4mm) plywood. I'm afraid the mast would drive itself right through the bottom. And anyway, setting up shrouds each time isn't exactly the definition of simplicity and practicality...

    Anyway, good advice. I'll keep it in mind for my next boat. Thanks.

  30. #30
    Join Date
    Nov 2014
    Location
    Kaunas, Lithuania
    Posts
    71

    Default Re: Sailing rig recommendation for this small boat?

    Hey, I wanted to clear up one little detail I could find on any of my books before I commit to shaving my yard. Todd, you said that making a tall and narrow yard won't work, because it will slip and flip on it's side, where it can easily break. However, your own yard on that lateen sail is 1.6x1.5", making that something like a 94% ratio, correct? I assume that little difference in height/width doesn't present a flipping problem. So, my question is, what's the biggest difference in height-versus-width you'd go in a lateen or lug sail yard? My gut says that if I don't exceed 80% (for example, 1.6x1.3") in a spar with heavily rounded corners, it shouldn't flip yet. Or would it? My 2x1.6" yard was around 80%, and it didn't slip under the halyard, but it didn't have corner roundings, so I'm not sure if rounding corners will present that danger. Could you or someone else give an educated guess? I just want to make sure whenever I should keep the height-width at that ratio, or square it off before rounding the corners

  31. #31
    Join Date
    Jun 2000
    Location
    Madison Wisconsin
    Posts
    8,296

    Default Re: Sailing rig recommendation for this small boat?

    Like I said before......put down the calculator and slowly back away.

    However, your own yard on that lateen sail is 1.6x1.5", making that something like a 94% ratio, correct?
    I can absolutely assure you that there wasn't the slightest hint of any ratio being employed when I made that yard. I eyeballed it until it looked about right to me.

    My gut says that if I don't exceed 80% (for example, 1.6x1.3") in a spar with heavily rounded corners, it shouldn't flip yet.
    How the hell does your gut have any reasonable idea of what 80% would or would not do? I have no clue what ratio would flip over and what ratio would not - and neither do you. As always, my advice to you is to start gradually thinning the spars and test sail them as you continue until you get something that works well. You are not going to be able to calculate the answer, no matter how much you want to, because you have no data to draw from.

    You would really freak out if you saw me build a sail. I measure the perimeter and eyeball or guestimate everything else, and have for about 25 years, yet they seem to work pretty well.

  32. #32
    Join Date
    Nov 2014
    Location
    Kaunas, Lithuania
    Posts
    71

    Default Re: Sailing rig recommendation for this small boat?

    Quote Originally Posted by Todd Bradshaw View Post
    You would really freak out if you saw me build a sail. I measure the perimeter and eyeball or guestimate everything else, and have for about 25 years, yet they seem to work pretty well.
    Well, this bit explains everything to me If I had that many years of sailmaking behind me, I would probably very confident in letting the calculator rest in the drawer too!

    Anyway, thanks for the quick reply. I guess I'll just go for it and hope for the best. I guess nobody became a sailmaker or sparmaker by pushing buttons on the calculator all day anyway.

  33. #33
    Join Date
    Jun 2000
    Location
    Madison Wisconsin
    Posts
    8,296

    Default Re: Sailing rig recommendation for this small boat?

    Don't get me wrong, I am not really against using calculators and formulas for this sort of thing. When I started making sails I used them a lot. Among other things calculating and essentially lofting out the sail design on a computer allowed me to build sails which were bigger than the room I was building them in. Compared to the work I had done on balloons, the sewing part of sailmaking was very easy and calculators and existing formulas made the whole design-from-scratch thing possible. It took a lot of practice and repetition to gradually work up to designing by eye. In this case though, you have a one-off boat and there really aren't any common formulas which seem to neatly answer the questions. Sometimes you just have to proceed with caution and see what happens.

  34. #34
    Join Date
    Nov 2001
    Location
    Seattle
    Posts
    20,935

    Default Re: Sailing rig recommendation for this small boat?

    What kind of wood are those spars?

    Todd's right, you just need to shave down those spars. Perhaps you could take a plane with you when you go to your sailing venue in case you decide more can come off.

  35. #35
    Join Date
    Nov 2014
    Location
    Kaunas, Lithuania
    Posts
    71

    Default Re: Sailing rig recommendation for this small boat?

    Quote Originally Posted by Todd Bradshaw View Post
    Don't get me wrong, I am not really against using calculators and formulas for this sort of thing. When I started making sails I used them a lot. Among other things calculating and essentially lofting out the sail design on a computer allowed me to build sails which were bigger than the room I was building them in. Compared to the work I had done on balloons, the sewing part of sailmaking was very easy and calculators and existing formulas made the whole design-from-scratch thing possible. It took a lot of practice and repetition to gradually work up to designing by eye. In this case though, you have a one-off boat and there really aren't any common formulas which seem to neatly answer the questions. Sometimes you just have to proceed with caution and see what happens.
    Well, I guess I am in that first stage you were in, still trying to fiddle around with formulas, mostly just to get a feeling of what works and what doesn't... Anyway, thank you, you have already helped me a great deal. Hopefully some other people will also find this information useful.

    Quote Originally Posted by johnw View Post
    What kind of wood are those spars?

    Todd's right, you just need to shave down those spars. Perhaps you could take a plane with you when you go to your sailing venue in case you decide more can come off.
    Baltic Pine (I guess). Just a general pine that grows around here. Not a very decent material, and definitely not readily available, but it's something. Yes, I will be shaving them down, I'll have a plane with me. If I manage to get a few new planks, maybe I'll even build a new yard altogether, some box section with heavily rounded edges or something. It might be a few months until I get that lumber, though.

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •