I realize that for some of you, this will be another “Oh no, not the same questions Again!”, but bear with me. For those of you that have spent your lives in this, you know more than I will ever know and you should know that I will never want to know All that you already know. I want to know enough to be ablt to start building a model from scratch and have it come out right. I spent my life in Plastics Injection Moulding. I know it very well. I always enjoyed teaching someone who did not know. Even when the question was one that had been asked by a hundered others. So I know that some of you must still enjoy teaching newbies, to sailing, like me, who don’t know anything about sailing or RC…
Center of Lateral Resistance (CLR) or (Center of the Lateral Plane, CLP)
I believe I understand what it is, but the method and the variables seem to get me in trouble. The more I read, the more I see that lots of people disagree.
1.- Can it be tested on our little model sailboats? How can it be done Accurately? I have read that it can’t be done without lots of math calculations and software.
2.- If it can be done, doesn’t it have to be done with the keel and rudder in place? If those aren’t in place, how can the resistance be measured accurately? If so, do you have to be able to “temporarily” attach the keel so you can move it for testing it’s placement and how it affects the hull?
3.- Also dosen’t it have to be done with the correct “running weight” in the hull, including servos, batteries, sails, mast, boom, fittings. etc.? So would it be necessary to know all those weights and lay ballast approximately in the same locations in the hull?
4.- I also read that in heavy weather, the CLR will change as each wave comes and the ship’s displacement changes. Also it changes when the sails are full and the ship heels over from the force of the wind/sails. Definitely the hull below the waterline is always changing as the ship moves, so how do you account for that?
I ask because for each question, I am finding many answers. Some say you can't do it on your own. Some say you can, some say just to use the middle of the boat, some say make a pattern of the hull at waterline and find the center of the pattern using a needle for balance??? Some say it takes math and software that the average person can never do. I see that some of the suggestions I have read, are totally wacked, even for a newbie/novice like me. Also I can see that I might not ever be able to really tell for myself, what the real CLR for any given boat will be, unless I find answers that I can understand and relate to. I would appreciate your answers on how You find out what the CLR is for your sailboats, or do you check? I could see that just putting on a keel about mid-point of the hull and makeing a "mast box" with a bunch of mast holes in it, could work by blind luck, just by moving the mast around enough to work, but that isn't good enough, right?
Center of Effort
I understand what it is, but how do you measure it accurately for any sail, for any type of sail (what is the proper method)?
1.- Does the Center of Effort in a sail not change in relation to the ship’s CLR as the sail is filled and the boom swings out? Is it necessary to take that into consideration when figuring out mast location?.
2.- I have read that the sail’s CE must be foreward of the ship’s CLR. I have also read that it must be aft of the ship’s CLR. What it the correct way and how much distance from the CLR? I have read anything from 2% to 12% from the CLR, or does that change with sail design as well?
I would appreciate in learning how You do your figuring for the relation of CE to CLR. I read enough to see that if this is not done correctly, it can really mess up the way the ship handles in the water and can turn a pleasureable hobby into a frustrating one. I prefer to "do it the right way first", before I mess it up, because I am not knowledgeable about ships, sails or water at all (except to drink and wash), so if I do mess it up, I won't know what I did wrong nor how to fix it. That's why I ask so many questions and I do so much research beforehand. I tend to beat a subject to death, so that when I start a project, I am fairly certain that I will be able to produce something that works properly the first time. If I cannot find acceptable answers, I don't take on the project, untill I do find them somewhere. That comes of my Production Management Philosophy from too many years in the plastics industry. I know some take the approach of try it and see what happens, but I have always believed in research first, answers beforehand and results that come out with less of "Murphy's Laws" at play during the construction. [u]Plus on a very limited budget, one has to figure it out first, to save on costs....[/u]
Thank you all in advance for helping solve these questions for me, in a way that I can understand.