Keith I will try the 250 lb load next Spring when I set up and see what happens to Mast rake as there is no backstay on a M15 Thanks George Merry Helen 96 M15 #602 George "We Can Not Control the Wind But We Can Adjust Our Sails" On Mon, Oct 31, 2016 at 6:11 PM, Keith R. Martin < keith.richard.martin@gmail.com> wrote:
Hey George,
My M17 rigging is set to provide about 250lb of tension on my forestay... Just trying to keep the forestay as tight as I can while respecting safe working loads for the 1/8 cable. Not sure how useful/valid this info is when translating to your M15, given it's a different rig set up... Hopefully others can provide some commentary on this topic for your M15
Cheers
Keith
*Keith R. Martin, P.Eng.*
*Burnaby, B.C. CanadaSerenity,** M17 Hull #353*
On 29 October 2016 at 17:30, George Iemmolo <griemmolo2@gmail.com> wrote:
*K*eith
I am sailing a M15 and the Reefing system uses a wire in the jib luff as the mast forestay along with the upper and lower rollers. No luff tape in this system. I did have a WWP 15 10 years ago with a system that had a extrusion and luff tape as did my last boat a Pearson 23. I had a Loos but it went with the Pearson when I sold it. What tension do you set your forestay to, I can borrow one for setting up next season.
Merry Helen II 96 M15 #602
George "We Can Not Control the Wind But We Can Adjust Our Sails"
On Thu, Oct 27, 2016 at 10:46 PM, Keith R. Martin < keith.richard.martin@gmail.com> wrote:
Hey George,
While I am not a "racing guy" and I don't try to wring out every last bit of speed, I do like maintaining my pointing ability heading into brisk/heaver winds... The CDI furler, pvc forestay extrusion and the jib luff padding all combined adds some distributed weight along the headstay resulting in "deeper/saggier" shape which can impair pointing ability into brisk/heavier winds.
So now with the furler installed I keep the headstay tension & related backstay tension a little higher to help maintain a flatter headstay shape while staying within reasonable bounds for the rigging ( I have a Loos gauge to measure the tension) all the while making sure I keep about 8" of mask rake which seems to work pretty well with my set-up ...
I am not saying that it points as well as a hanked on jib set-up, but in my experience the improvement is noticeable..
The Elliot Patterson website has a decent summary on head stay sag that can be found here -> http://www.epsails.com/Headstay%20sag.htm
Cheers,
Keith
*Keith R. Martin, P.Eng.*
*Burnaby, B.C. CanadaSerenity,** M17 Hull #353*
On 27 October 2016 at 18:58, George Iemmolo <griemmolo2@gmail.com> wrote:
Keith
Your comment on proper headstay tension is of interest as I have a 109 on a CDI Furler. Can you elaborate a bit on the subject?
George "We Can Not Control the Wind But We Can Adjust Our Sails"
On Thu, Oct 27, 2016 at 3:41 PM, Keith R. Martin < keith.richard.martin@gmail.com> wrote:
Hey John,
I had an old 120/130 ish (more than a 109 and less than a 150) hank on head sail that came originally with the boat...
For me I think there is a substantial safety benefit in a furler for single handing, which for me is most of the time ..
I now have a 109% on a CDI furler.. I have found it's been a good compromise for single handing the boat up and down the Georgia straight. Certainly there have been some lighter wind days in the summer that I have yearned for a bit more head sail, but there have also been plenty of days when I have had a reef or two in the main and been very thankful for the 109 on the furler...
As we all know there is a trade off on pointing ability with a furler and particularly once the jib is partially furled hence my choice of a 109 that allows me to defer "reefing the jib". That said the boat performs and points pretty well with no reef or a single reef in the main and the 109 on the CDI fully deployed (with some attention paid to proper forestay tension) and has just okay performance when the 109 is furled just a bit, after that deeper furling is not all that stellar ( that's Canadian for it sucks).
I toyed with putting a 120 on my furler when I first bought it but frankly I had not spent enough time in the boat in the straight to be sure it was the right choice for me... In retrospect while a larger jib on the furler is probably okay for summer, the fall and spring shoulder seasons up here generally have no shortage of wind, so I think the 109 is a good all season choice for my sailing in "my hood" ...
Just my perspective on the choices I made for my boat and the local conditions I single hand sail in.
Keith
Keith R. Martin, P.Eng Serenity, M17 Hull #353
On Oct 26, 2016 7:21 PM, "John Schinnerer" <john@eco-living.net> wrote:
Thanks, that means my 80%-ish Reggie Armstrong jib is probably the original "high wind" jib. I didn't get a 109% with the boat, just the 80% and the 150% genoa. I mostly single-hand, or have passengers that are not really "crew" (they ain't gonna change a headsail under way), so something like the 109 working jib would be nice to have.
Or, a furling jib...
cheers, John S.
On 10/26/2016 05:41 PM, Judith Blumhorst, DC wrote:
> Hi All, > Just for those of you who are curious about sail sizes: > That calculator is pretty cool, but it understates the real LP% by a > small amount. The sail has a curved surface, but the calculator is > computing the shortest straight-line distance between two points on the > curved surface. This kind of measurement is referred to as "geodesic" The > true LP, when measured on the sail itself, will always be slightly bigger > than a geodesic-space calculation indicates. > Sail design software computes dimensions along the curved surface of the > sail. > BTW, according to the original sailplan that Jerry so generously sent me, > there was an 80%-ish LP Heavy wind jib. Also a 109%, which is a great, > versatile working jib for the M17. > Regards,Judywww.HydeSailsDirect.com > > > > On Sat, Oct 22, 2016 at 2:04 PM, John Schinnerer < john@eco-living.net
> wrote: > > Tidying up my sails, finally doing some measuring... >> >> My "small" jib is not the 109% standard or working M17 jib, it's quite a >> bit smaller. Here's one calculator I found: >> http://sailingfortuitous.com/apps/jibcalc.html >> >> This and other similar formulas found online put it at about 81-82% (luff >> 189", leach 160", foot 76"). In between a working jib and a true (like >> 60-65%) storm jib. >> >> Also played with the outhaul method shown in that video I posted >> recently. >> Really a good idea AFAICT. Works as clew strap and outhaul both; >> automagically balances the angle of pull on the clew. >> >> And, makes it much easier to move that same outhaul line to a different >> reef grommet - no need to tie or untie any knots on flapping sail in >> bouncing boat. Just loose the outhaul, pull out of current grommet & >> block, >> route back through new grommet & block & make fast. With a boltrope or >> slug >> footed sail of course. This would be a Very Bad Idea on a loose-footed >> main...! >> >> cheers, >> John S. >> >> >> -- >> John Schinnerer - M.A., Whole Systems Design >> -------------------------------------------- >> - Eco-Living - >> Whole Systems Design Services >> People - Place - Learning - Integration >> john@eco-living.net - 510.982.1334 >> http://eco-living.net >> http://sociocracyconsulting.com >> >> >> > > -- John Schinnerer - M.A., Whole Systems Design -------------------------------------------- - Eco-Living - Whole Systems Design Services People - Place - Learning - Integration john@eco-living.net - 510.982.1334 http://eco-living.net http://sociocracyconsulting.com