I found an interesting low cost stepping motor with an attached gear at Pollin:http://www.pollin.de/shop/dt/Mjc1OTg2OT ... 2_038.html
This unit is also available from All Electronics (CAT#SMT-107) in the U.S.A.:http://www.allelectronics.com/make-a-st ... ors/4.html
It's a bipolar one with a step angle of 1.8°. The impedance of the coils of the two phases is rather low with 6.5 Ohms each. Therefore it's necessary to use a low supply voltage for the driver not to overheat it. I have tested the built-up motor scanner with the EasyDriverV3 and with a driver board from Markus Mechatronics.http://www.watterott.com/EasyDriver-v3- ... tor-Driver
and then click on „Driver selfbuild kit“.
Both drivers are microstep ones and were used in 1/8 step mode. The supply voltage was 7.5V. Additionally a heatsink was glued with an epoxy resin adhesive onto the IC A3967 of the EasyDriver. The SMD potentiometer on the EasyDriver board was turned to left to its output current minimum of 150mA.
The gear around the stepping motor isn't performed with its cogwheels in one physical line but with three different endings. Unfortunately no output shaft is available. The ending with the highest gear ratio (17:1) is used to pivot the laser. As you can see on the photo a copper sleeve is glued directly with an epoxy resin adhesive at the helical cut cogwheel and a tube with a knurled screw is clamping the laser.
In the 1/8 microstep mode the laser has a resolution of 0.013° per step.
As a controller for the driver an Arduino microprocessor or a clock generator like this can be used:http://www.david-laserscanner.com/forum ... 9462#p9462
The direction of rotation must in the last case additionally chosen by a toggle switch (Gnd or +5V to the DIR input).
The newest version V4 of the EasyDriver has some advantages over the former V3. E.g. a more robust potentiometer, the possibility to change the step subdivision and to power down the output stage.
All the best for the new year and have a lot of fun with DAVID!
P.S. Take care not to give clock rate impulses or the direction signal to the inputs of the EasyDriver when its power supply isn't switched on. By neglecting this I have just damaged the DIR(ection) input of an EasyDriver.
Edit 1: Here you can find how to connect a stepper motor via the EasyDriverV3 to an Arduino:http://www.david-laserscanner.com/wiki/ ... re_project
And also here:http://www.david-laserscanner.com/forum ... 366#p12366
Edit 2: In the meantime I have made a test in planeless scanning with this device. You can find it here in my second post of Jan 16th :http://www.david-laserscanner.com/forum ... 405#p10405
Edit 3: You can also control this stepper scanner by the Arduino and the Adafruit motor shield on it:http://www.david-laserscanner.com/forum ... t=30#p8155