I wanted to share a photo of the box of goodies I got from Bob Holman. He is currently cutting the wing nose ribs, the aileron nose ribs, all the empennage gussets, and the square gussets on the ailerons. Sure saves a lot of time with the use of some modern technology.
Maybe Team provides these as well, not sure. I think you have to buy their rib kit in order to get them.
I am a strange combination of frustrated and overjoyed now. I have access to a laser cutter at a local shop, so I can do this as well. I also spent quite a bit of time making jigs to cut these on my table saw, but the laser cutter will still be a better way to do it. Thanks for the suggestion!
Did you bother sanding the char off of yours? I got mine done a few weeks ago and I've been sanding it off but lately I've been questioning whether it's worth the effort. It might look a little less professional, but the ribs are all going to be covered up anyway. I can't imagine it's going to affect the adhesive at all - the edges shouldn't be where that gets its strength, anyway.
How does one transfer the dimensions to be cut to the cutter.Can it scan the drawing to get the dimensions? I know someone who cuts model airplane parts for his kit business.He might be able to help.Will save a ton of work I am sure.
What I would do is scan the page and draw the parts out, and then just in the software, scale until you can match the measurements in the plans. Unless your prints are actual size, and the scanner DPI is known. Then just trace it in software.
If you have a scanner large enough, that could work. I just measured all the parts on the drawings with a ruler with 1/64" increments (almost all of them lined up on a 1/16" increment anyway) and made drawings from those measurements in a 2D CAD program. I also combined a lot of edges with mine so that one pass from the laser cut multiple parts (I forgot to photograph this, but I attached a screenshot of the drawing I used with the laser cutter to show what I mean). This occasionally had the effect of the laser cutting a bit of material into the edge of one part when cutting another, but it's subtle and I've only seen a few minor instances of it so far.
For the nose ribs I used a method similar to what ITman496 suggests - I put my camera on a tripod and took a photo of the plans hanging on the wall, then another photo with a 0.5" grid held over the nose rib, and used GIMP to make the grid photo partially transparent and line up with the background photo. I then traced the outline of the nose rib in InkScape and saved it as a DXF file. The InkScape DXF extension was broken (this may have been fixed, but I can't find the source for it) so I had to hack away at it a bit to make it work. You may be able to use SVG with your laser cutter and skip this step (or just use a different drawing program).
One crucial thing to remember is the laser is very fine and very precise, but still has kerf. After making my drawings but before copying them into the pattern that was fed to the laser cutter, I offset all the lines .025" outward. This gave me slightly oversized parts (the parts list for the kit suggests these should be made from 7/8" [0.875"] wide strips of plywood, and a gusset I just measured is 0.914" tall) but I'd rather have that than slightly undersized.
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