(The third time is the charm, I hope. Links to downloadable forms are below) If all you want is a quotation, the IJP and E are adequate. Once you accept the sailmakers quote, the sailmaker will send you a form with thegeometry they want and are used to using. Here are measurement forms showing the measurements I require for a custom-fitted sail. There's enough data here for me to figure out missing measurement using geometry. In my experience, customers who measure their rigs before asking the sailmaker for a measurement form don't provide the right geometry to design a sail. If you send me a different set of measurements, I'm going to require that you fill out this form anyway, following my instructions. I'm used to doing the geometry a certain way. Headsail measurement forms: http://dl.dropbox.com/u/20774907/measurement-forms/HydeNorcal-Genoa-Measurem... http://dl.dropbox.com/u/20774907/measurement-forms/HydeNorcal-Genoa-Measurem... Mainsail measurement forms: http://dl.dropbox.com/u/20774907/measurement-forms/HydeNorcal-Mainsail-Measu... http://dl.dropbox.com/u/20774907/measurement-forms/HydeNorcal-Mainsail-Measu... Judy Blumhorst Hyde Sails of Northern California www.judybsails.com judy@judybsails.com cell: 925.208.1692 fax: 925.820.2327 skype: judith.blumhorst www.HydeSails.com/NorthAmerica ________________________________ From: "Judith Blumhorst, DC" <drjudyb@blumhorst.com> To: For and about Montgomery Sailboats <montgomery_boats@mailman.xmission.com> Sent: Saturday, March 31, 2012 10:27 AM Subject: Re: M_Boats: Sail Measurements Confusion For those of you who wonder what measurements you need to supply to a sail maker, there are two answers. If you're looking for a quotation, all you need to supply is the I, J,P and E. If you're off by a couple of inches it won't matter in terms of price. (In terms of design, 3" on the luff is Once you have chosen your sailmaker, you need to supply a lot more measurement. However, if the sailmaker has made lots of the same sail before, they may not need all of the measurements. We usually have a "stock" design that will fit most boats. Here are the links to the measurement forms I use. There are a lot of measurements that go into the design of the sail, include matching mast rake, bow shear, location of genoa tracks, etc. Headsail measurement form - pdfMainsail measurement form - pdf Headsail measurement form - xlsm Mainsail measurement form -xlxm Judy Blumhorst Hyde Sails of Northern California www.judybsails.com judy@judybsails.com cell: 925.208.1692 fax: 925.820.2327 skype: judith.blumhorst www.HydeSails.com/NorthAmerica ________________________________ From: jerry montgomery <jerry@jerrymontgomery.org> To: For and about Montgomery Sailboats <montgomery_boats@mailman.xmission.com> Sent: Saturday, March 31, 2012 7:59 AM Subject: Re: M_Boats: Sail Measurements Confusion Actually, it goes down to the extended deck line, not the sheer. You pretty much need a sailplan drawing to do it accurately, because you need to project the deck line aft, on the centerline, ignoring the house, to the point where the extended front edge of the mast would intersect with it. You use the same imaginary point for calculating the J. When you measured the mast, you didn't include the masthead, did you? It should be 10' even; I just doublechecked the sailplan. #176 would be one of the boats that I made, and I used to buy the masts directly from the extruder, 1000 lbs at a time, cut to length. If it's longer than that, its got to be an aftermarket mast. I told someone incorrectly, a while back, that the mast was 19'6", but that was the M-12 I was thinking of. Hope this helps. If you have decided on a sailmaker, I understand that he/she can get a sailplan off the internet. If not, have them email me. jerry ----- Original Message ----- From: "Jeffrey Johnston" <frjeff@gmail.com> To: <montgomery_boats@mailman.xmission.com> Sent: Saturday, March 31, 2012 5:48 AM Subject: M_Boats: Sail Measurements Confusion I am attempting to measure my M15 to determine if it is "standard" sail measurements or not. I already have determined that it is a bit different than some specifications given for mast length: my mast length appears to be 19'2" (Hull 176 - 1981). My confusion lies in the "I" measurement. Some measuring guides tell me to measure from the jib halyard block down to the deck (the cabin top). Another says to measure down to the deck sheer line (as if there were no cabin). Not sure how one would get that number in an attempt to guesstimate where that sheer line would be on our 15's. Which of these is the correct "I" measurement for a sail loft when having sails made? Jeff PS - It appears that I may never run out of questions for this group. Thankful that this group is so patient and helpful. *Jeff+* Molōn labe!