With regards to luff treatments, what kind of wire does everyone use for luff-lines, jack-lines etc?
I have always used 30lb fishing leader wire. The problem with this is stuff is that it?s too flexible, and will not slide up the luff pocket. Thus when I make sails I always place the wire in the pocket as I’m making it.
Last night I was messing about in the shop and I tried using a short length of ?music wire?. It was stiff enough to slide into the luff pocket with no problem. Has anyone used music wire as a luff line? If so what diameter?
I was thinking of ordering a coil of .024?diameter Stainless steel and doing some further testing.
I’ve tried using stainless single strand ‘piano’ wire with no success. When the wire is manufactured and coiled onto the spool it takes up a ‘set’ and it is impossible to straighten it out. This makes it impossible to slip up the luff pocket and when the sails are not rigged on the boat and tensioned for use, the luff takes up the ‘set’ of the wire. Only use this wire for standing rigging, or better still the flat rolled single strand. Having been rolled, it wants to lie flat. Laid up 7 strand wire is the best for luffs as it automatically wants to straighten out.
dan
this looks strange to me. the luff ring. does it not look simular to the ILEAGLE, black majik sails, the only difference would be the size of the hole. as for piano wire. never used the stuff. i use the rc controline branded wire. it is tough and never gives up. I think it is also way overkill. your pianio wire idea may work. i look foreward to hearing how it does.
cougar
OK. I’ve tried again to photograph my latest mainsail for Accumeasure purposes and have once again failed miserably. Just you can see what I’m up against, I’m posting 2 images - out of about 10 that I’ve taken with and without flash - indoors and out. The mylar tinting fabric is so reflective, I just can’t get a decent result.
The reflections give the apprearance of creases and distortions that in fact are not there.
Then I thought I would try printing one of the photos, drawing the “shape” in with a marking pen, and then scanning the result. That failed too. You can see below that the lines drawn in suggest that the first and second curves feature a very flat entry, with draft probably more than 60% of chord, and with a bit of a hook in the leach. While the foot and the top curve appear pretty much as intended - draft at 40% of chord and a relatively common percentage of draft up the sail. Obviously it was just as difficult for my eye to follow the curve on the printed image as it is in the photo on screen. When viewed in person, the first curve pretty much follows the foot, (as you would expect) and the second curve also looks pretty good. So my eye and artistic abilities with the marking pen were a disaster and the result does not represent reality.
Oh well - back to the drawing board. :sad:
The good news is that the sail itself looks and sets much better in the flesh, than it appears to in these photos. We’ll run some informal races at the club tomorrow so I’ll see if I can get some on-the-water shots.
This was the photo I chose to print…
And this was the result after my amateurish effort to draw in the lines…
Nope this method is legal, because the wire goes from the head to the foot in one piece, Blackmagick sails used to be made with lots of little wire segments. Multiple segments was said to be ilegal.
One point of interest for an Victoria sailors reading this - note the degree of bend in the mast.
Most Victorias are built with carbon masts - many tapered and many with jumper struts at the level of the hounds to “control” bend in the top third of the spar. In this rig I’ve used a thin-walled aluminum section (not the kit mast) which is only slightly heavier than many of the carbon alternatives. There is a single set of spreaders (carbon) and single shrouds - but with a set of check stays down low, that join the mast not far above the gooseneck. To some extent the check stays can be used in the way that deck chocks are used on a keel-stepped mast (Victoria masts must be deck stepped). The check stays should also be enough to hold the mast up in the event that a side-stay fails while sailing. This means that there is minimal standing rigging, and therefore minimal weight and windage aloft.
Using the thin-walled aluminum mast allows it to be pre-bent forward as is common practice with certain spars on the A Rig in the IOM class.
Thus this mast has been prebent forward - and the mainsail designed for a mast bend of 5mm aft. With sufficient backstay tension to achieve that 5mm bend, the forestay is thight and straight. Thus far I’ve sailed the boat with the mast set between straight and 10mm of bend (easily measured by using a straight-edge placed between the gooseneck and the masthead). With this mainsail, a straight mast tends to pull the draught too far forward for my preference in light airs - so even in the light stuff I think I’ll be setting the backstay to induce a few mm of aft bend.
Whether any of this will work in practice - only time and racing will tell. But it’s a little different than “standard” on a Victoria - so just thought I’d share.
Muzz -
maybe paint a piece of foam-core board flat black and position just out of camera range to reduce the reflections back on the mylar?
Just a suggestion, don’t know if it would help. Most are using mylar that is translucent or opaque but drafting film quality. Maybe have someone hold dark fabric and see if that reduces those reflections any.
Yes - I had thought about trying something along those lines - but it may may not be worth the effort to make up something just for this. These are still the temporary/experimental sails, and the final sails on this boat will be made out of TriSpi or light drafting film - both of which are more normal for the class and neither of which will be highly reflective when I photograph the result.
I’ll look around the house for something suitable to use as a background and see what I can come up with.
muzza
my first pictures has the same problem. they looked like my sails were glowing. maybe from 3 mile island. so i just had to play with lighting. and i put the boat behind the light… it worked better. and when you take your pictures for the acuumeuasure. this may help.
I am thinking or using black eletrical tape for the lines. then post the picture. when the boat goes back into the water . all i would have to do is just take the tape off
as for dan and his piano wire. it would be a lite wieght solution to problem. i know of people just starting off , that used string.
cougar
Here are the Accumeasure results, and a bit of my spreadsheet showing the corrected data for the main. The numbers look good; the aft max draft of the bottom main seam is caused by the outhaul giving no draft in the foot, as far as I can see. Are the reported numbers for measured camber (around 10.5% in main, 9% in jib) what you intended? And, is the draft position (around 40% for both main and jib) what you wanted as well? If so, I’d say your broadseaming is spot-on. Just need to ‘fix’ the finishing of the luff tape etc.
Free sailing boats can take some pretty horrific hits at the side of the pond if your (or somebody else’s) old legs aren’t up to the task After a couple of dismastings you learn more than a bit about strong rigging. One very important lesson is to avoid the coated cable–it’s easier on the fingers, but almost impossible to get a really strong crimped joint. Here’s what I use:
Sevenstrand brand “Toothy Critter” stainless cable from the good folks at Charkbait:
The Sevenstrand cable will stretch over time. I pre-stretch it, and test my crimps, by using an old spring pull scale. I use the 90 lb cable on M and 36R, and pull-test to 60 lbs. Despite being careful with my crimps, about one in a dozen or so will let go under test.
I do three crimps: one along the sleeve, not very hard, to hold the loop in place, and then two really hard ones in an “X” pattern diagonally across the sleeve. Before crimping I slip a piece of heat shrink tubing over the cable and slide that over the sleeve and the “fuzzy end” of the cable and shrink it down. This looks shipshape and saves a lot of finger pricks from the cable ends. I also use thimbles from Small Parts where the nature of the fittings permits.
?Music wire? also known as ?Piano wire? is different from guitar strings. Is has been 5 or 6 years since I?ve used a guitar (college roommate tried to teach me to play) but the strings were brass/nickel. Music wire is usually a single strand of stainless or high carbon steel.
SmallParts does sell 60? lengths of perfectly strait music wire, so for smaller models you wouldn?t need to worry about straining it.
This thread is really helpful, as I’d like to make some better sails than my weak attempts to date. Since my current emphasis is on Footys, I’m interested in your opinions about making a sailblock. Since Footy mainsails have only about a 20" luff, do you think 3 degrees is still an appropriate angle, or would that introduce too much camber into the smaller sail? In other words, is the camber angle scalable to all sizes of sails?
After a couple of dismastings you learn more than a bit about strong rigging. One very important lesson is to avoid the coated cable–it’s easier on the fingers, but almost impossible to get a really strong crimped joint. Here’s what I use: