Sunday, November 30, 2008
I manufactured a second copy of my bracket and used my hand drill to put a few holes in them to hold bearings. The idea is to mount 3 inline skate bearings at 120 degree increments around a pipe to limit motion to 1D (two of these on one side, plus two 2D mounts on [...]
Saturday, November 29, 2008
I have designed a bracket that I used as my first attempt to manufacture something with my CNC mill. Because I’m still using python code I wrote myself and have not yet calibrated my stepper coordinates into real-world measurements, I had to design the bracket in Inkscape, print it out, and manually move my router [...]
Friday, November 21, 2008
Checking Accuracy
Using my simple router code I had the X/Y table plot a square with a circle inside of it (and then added some extra code to draw a smaller circle inside that). The first time I tried this I found that one side of my X/Y table was significantly (1mm or more) lower than [...]
Tuesday, November 18, 2008
I received the new and improved serial stepper controller board (version 4) from Ocean Controls. (Cost: 65 AUD) Although it supports up to a 6kHz stepping rate, I found that my steppers can only be driven at the RATE 12 setting, or approximately 745 steps a second. I’m not sure if this is because I’m [...]
Wednesday, November 12, 2008
I have added limit switches to my X and Y axis. I always planned on adding them eventually, but after I stripped the nylon threads on one of my flange nuts in a router accident I decided that it was time. I’m using small micro-switches mounted such that they are closed when the X or [...]
I purchased the 3 stepper motors from a surplus supply house for $25 each, and have been very happy with them. The fact that they include a screw drive mechanism has really simplified my mechanical construction. They are manufactured by HSI inc, and are Model 43000 external linear actuators.
The electronics that control the stepper [...]
Since my last post I have constructed the Y table servo mount and pusher assembly. The Y-axis servo is mounted using a pair of L-Brackets, M4 machine screws, washers and nuts that were purchased specifically for this project and actually fit the screw holes on my servo! (Unlike the X-axis servo, which is connected [...]