Archive for July, 2008
CamBam Plus has the option to automatically generate tabs. This is pretty nice and might make me change how I use fixtures to hold workpieces down. I’m starting to have concerns about the double-sided carpet tape, as I’ve seen the wood moving slightly during cutting.
I decided to create a simple test – cut a 0.5″ x 0.5″ square with tabs, in 1/4″ poplar. Also I cut the entire piece out so I could examine it and show it off to people (total size is 1″ x 1″).
CamBam Plus automatically generated the position of the tabs, but I needed to decide on the height and thickness. My first test using tabs with gears failed as the tabs were so thin they were non-existent. In this test they are 0.1″ wide and 0.07″ high. In order to saw the tabs later the outer profile cut has to be wide enough to get a tool in there. In this test it is 0.125″ wide.
The feedrate was 10IPM.
Here is the video – the final piece is shown at the end. In the EMC2 image you can clearly see the tabs at the bottom of the cube on each side. Sorry about the poor quality.
Today it was time to give some new gear generation code a try. Using CamBam I created gcode for a gear with a 2″ pitch diameter, 18 teeth, 20 degree pressure angle and a diametral pitch of nine. I then cut a couple of them out.
The original plan was to work on precise cutting of two sides of an object. That idea failed so I had to eyeball it. Here is a video of my Fireball CNC V90 and EMC2 (running on Ubuntu Gutsy) in action:
The gears fit together nicely.