Friday, September 2, 2011

A key piece


Back when I purchased the MultiCam CNC router I had doubts whether the machine could effectively make single small pieces cost effectively. I was told the machine would best be used as a production tool but I had no interest in doing production work. I can now say with authority that the router is a wonderful tool for doing detailed pieces singly or in small runs. I work quickly but the machine can do this type of thing five times faster than I could do it by hand - even counting in the design time for the files. Best of all it works while I do something else.

One of our current projects is a faux brick archway between the pub and the entry area. Yesterday I was discussing details with the owner. She asked for a keystone in the arch - with some detail carved in. I suggested the letter 'D' for Dan or Debbie...  depending on who saw it.  While the brickwork will be hand carved from concrete, the keystone was best made on the router.


I made up a quick sketch on a piece of plywood to test the size. It looked good.


The first step was t create the vectors in EnRoute. the keystone measures 11 inches tall and about 10 inches wide at the top corners. To minimize routing I would create a relief  of just the background inside the border and then apply a texture bitmap. The pieces would be routed from 1.5" thick 30 lb Precision Board.




I used a bitmap from the TEXTURE MAGIC collection, enlarged it and applied it using a value of 0.2". The black does nothing, whites raise by 0.2" and the grays are in between. 


The tool path was simple on this piece. For the background routing I used a single too, a 3/8" ball nose bit with a 90% overlap. To cut the files out I used a 3/8" end mill. 



The file ran in a few minutes while I answered some emails. 


Next week I'll show some pictures of the keystone installed with the bricks carved around it.

-dan