Hi, How do you handle the fact theat the ribs syrfaces are flat and the shape of the hull is curved? If I were building a plank-on-frame model I would align the edges of ribs so that the forward edge of the ribs touched the rib position in the bow and the trailing edge touched the position in the stern. This works because the planking spans multiple ribs and just touches the edge of each rib. However - we sheet our models and the sheeting must adhere to each rib. This will give a very wavy look since the edges touching the ribs will be glued to a flat surface. My guess is that I should align the ribs opposite of the way it is done on plank-on-frame (ie trailling edge at bow, leading edge at stern) and then sand the ribs to the curve of the hull. Is this right?
Or you let the balsa fit its own curves, and fill in the gaps with glue. I have found that, except in a few very rare instances, the ribs are not quite perfect. There exists some ripples, or incorrect curves, etc that, when you stick perfectly to the ribs, cause bumps, lumps, cracks, and other problems with the skinning process. When I sit back and only roughly match the wood to the hull, and fill in the gaps, the result is a whole lot prettier. That also helps me locate problems in the ribs, which I can fix for future builds.
I tend to use a simple sanding block to bevel the rib edges. Of those acute curves on the bow, I may switch to a a curved piece of sandpaper or even a large dowel with sandpaper on it. As for rib placement, you are pretty limited most of the time by the rib locations on the plans.
It is possible to draw new ribs for locations not included on the plans. It's tough to do right, and it is easy to make a mistake and cause unwanted dips or bulges in the hull. I have seen people free-hand draw between to ribs, calculate a new rib based on the measurements of specific points on several nearby ribs, measure a new rib using horizontal sections, and even draw up ribs for a hypothetical ship based only on plan and profile views. It helps to have a flexible ruler and an eye for curves. A basic knowledge of calculus can't hurt, but isn't necessary.
I've got a pretty simple technique that I use. I threw together a quick "how-to" document & uploaded it to the File Manager: http://www.rcnavalcombat.com/rcnavalcombat/FileManager/ViewFile.aspx?id=2297 Ever get a good, up-close look at a real ship? There are "dips & bulges" all over the place. They get some pretty hard use in real life. The real thing never looks anywhere near as clean & pristine as a "fine model" does. JM
John, that's a slick presentation on how to do frames! Nicely done! It's also too much for a poor Tugboat to absorb before his morning coffee But I saved it and will read it when I'm properly braced for the day and my CNS is online. It also continues to worsen my 'Does Everyone But Me Have the Full Version of Acrobat' complex
Thanks! That was really just a "quick & dirty" documentation job, so let me know if anything doesn't make sense & I'll see if I can fix it. If you mean the reader, that's available free from: http://www.adobe.com/ If you mean generating .pdf files, that's easy, too. I use PDF995, which works just like another printer (i.e. "print to .pdf"). It's also free (actually, "ad-ware" unless you want to pay a little to skip the pop-up ads): http://www.pdf995.com/ JM
if it will make you feel better, I tried to install acrobat 8.2 which managed to render it so I can't open any pdf files. I have to dump my system and start over... just not today...
