I made some appliqués for Extreme Makeover: Home Edition
. I thought telling the story of how they were made may help others to use the same technique, or hopefully improve the technique.
) is a designer for the show and she was aware that I was doing some other work for the show. Nancy hand drew the following saying this was a simplified version of a theme she wanted to use in the nursery. It was sent it to me as a jpg directly from a digital camera. I don't know if she drew this free hand or if she traced it. In either case, Nancy is an expert in design and seemed to know what level of detail would work.
I took the image into Photo shop and used brightness and contrast to blacken the lines and white out the background. I then used a Gaussian blur filter to get rid of some of the "jaggies" and to make the lines of consistent width, followed by another round of brightness and contrast redefine the boundaries of the lines one more time. I used Photoshop for this but one could use almost any picture editing software for this step.
Inkscape (free on the web) was used to trace the drawing and create a .eps file for V Carve. Not only does it do an excellent job of tracing, it also seems to further smooth the drawing.
I used V Carve to create series of previews of the appliqués from 0.125 to 1.0 inches thick. The following is 1.0 thick.
The previews were sent to Nancy with a message that the "frames" wouldn't be in the delivered item. She liked the 1.0 inch thick preview and the artwork was revised to include a wider margin between the "frame" (which is scrap), and the appliqué.
I glued up two 3/4 sheets to form a 1 1/2 thick block of MDF 20" x 31.5". (Use lots and lots of glue. The MDF just sucks it up.)
I told V Carve that I would be using a V bit and that I would be using an end mill to clear the pockets which were to be 1.050 deep. V Carve puts the V Bit “stuff” and the end mill “stuff” into to two different files to accommodate the bit change. I lied to V Carve; I had no intention of using the end mill but it prevented V Carve from trying to cut the flat portions with the V Bit. Then I started cutting … well … OK, I didn't do the cutting, the shopbot did all the cutting and I dropped by occasionally to check on the progress. Swinging a 1 and 1/4 inch V bit, the design horsepower of my router was soon exceeded and the feed rate had to be slowed from 3"/sec to 1"/sec.
With the V Carve complete, the frame and some pretty ugly waste chunks still remained. The work was turned upside down and the back was milled until the piece was 1.1 thick. This left just enough strength to handle the piece to get it over to my drum sander. The sander was set to 1.0 inch and a slow feed rate. The finished piece emerged from the sander with the scrap falling away. The sander may not have been necessary, but I was afraid to use the shopbot to cut the appliqué loose.
Since I had left and right pairs (two sets of two) I taped the pairs back to back to protect the edges. After I left, the production crew attached the appliqués to the doors and this is the final product.
Two things of note:
1. Nancy said she didn't really expect the V Carve preview to be representative of what was going to be delivered. She was surprised when “the delivered parts were exactly what the preview had predicted”. I have seen similar comments on the forums. This is a tremendous benefit where the product has to be "sold" before it exists.
2. At no time did the artwork get "reworked" to get the final product. No hand manipulation of vectors or any such work. The final piece was the direct result of the original sketch. The entire process could be completely automated with no human in the loop. I'm not sure that I like that.
Overall, it was an interesting experience; I met a lot of good people and learned a great deal. I hope the process will be useful to others.
PS I was astonished to find that cutting 4 appliqués created almost 40 gallons of wood dust!