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I would like to cover the use of lasers in model building before getting into the setup and building of the model. Very little has been done by hand in the fabrication of parts. The majority of the work was done in a CAD (Computer Aided Drafting) program then parts were setup in a cutting file for the laser.

Breaking apart the pieces (click to open/close)
All the frame parts, deck beams, back bone pieces and the deck knees were nested as close together as possible on a 2 x 24 inch sheet of Boxwood. A small bridge is left holding each part in the matrix. A little twist of the part will break the small bridge and the piece will fall out.
Laser close-up (click to open/close)
A close up of the parts show what appears to be a burn from the laser. Actually it is not a burn at all but rather the smoke from the cutting process. This smoke can either be scraped off with a razor blade or cleaned off with steel wool. The darker squares are the notches etched into the parts. These notches are for the ends of the carlings and ledges.
Laser Cutting (click to open/close)
It's the nature of a laser to cut on a slight angle. The laser beam losing focus and spreading out causes this. This photo was taken with a close up macro lens and the actual angle can barley be noticed.
Correcting an angled cut (click to open/close)

Both photos are examples of both sides of a laser cut when joined together. The first photo is of the front side of the pieces, when turned over the space is much wider due to the angle of cut. Remember this is very close up photography and the gap is no more than .008 thousands of an inch. The ridges in the background fabric can barley be seen with the naked eye. Correcting the angled cut of the laser is a simple task. Take a file or sandpaper and file along the edge.
Joining laser-cut surfaces (click to open/close)
Very little material has to be removed from the joining surfaces to obtain a close neat fit. The seam in the photo is less than half the width of the ridge on the edge of a penny. There is no need to remove all the burn from the joining edges. Epoxy will bond to the edges with no problem.
Squaring up the notches (click to open/close)
Some edges with an angle are more critical than others. Looking down on the notches cut into the keel you can see a slight angle to the edges. Two or three passes with a file and the notches will square up.
Cleaning up laser smoke (click to open/close)
The keel was dropped back into the matrix piece after it was cleaned up to show there is no trace of the laser smoke. This clean up took only a few passes with a razor blade. What is seen on the edge of a laser cut piece is not a burn but rather the resin from the wood. There is no burnt or charred wood along these cuts. I measured a piece before and after the resin burn was removed and only .003 of wood was actually removed. When the parts were laid out for laser cutting the width of the beam was taken into account and the actual cut was offset. The model is designed within a tolerance of .006 of an inch.

Go to part 3 - BUILDING THE FRAME

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