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Laser Light Show

Introduction:
After a failed attempt to duplicate the home-made ELM-Chan galvos, I decided to begin my lightshow experience with some commercial components, and go from there. The goal for this project was to learn about laser light show equipment while building a semi-professional grade projector capable of the 12k ILDA standard, for as cheaply as possible! By the time I'm done it would probably have been cheaper to buy a cheap set of pre-tuned 30k galvos from E-Bay, but where's the fun in that?

Description:
My projector uses two old General Scanning G120 galvos from E-Bay, and a LaserMedia LM22SDA 2-channel galvo amp also from E-Bay. The galvo mirrors were likewise purchased on E-Bay (notice a trend, here?) and are a perfect match for the G120s.
I have designed the projector in a box which formerly housed an optics assembly for a GE CAT Scan machine. There is an internal 5mW 532nm DPSS Laser pointer for quick and easy demonstrations. However, I have designed the projector such that the corner reflector mirror can be removed and any external laser may be used with the X-Y galvo pair. Blanking is not currently supported - that's next on the list.

Here are some pictures of the laser projector:

And the system output - before and after tuning:

In order to test the galvos and amplifier I built a G120 "Breakout Board" to let me monitor the galvo commands and manually-induced feedback signals. I have also included a couple pictures of the prototype system.

To generate the galvo commands I am using the internet standard DAC0832 D/A converter. It generates an X, Y, and Blanking signal using one of a number of free computer programs. I output these signals to RCA outputs to allow the use of easy-to-find A/V cables to interconnect components.

Design:
Mechanical:
In designing and constructing the galvo bracket and mount, I generated a Solidworks Model for the G120 Galvos and galvo mirrors to check fit and dimensions in the model. Click on the image below for the models - Feel free to download and make use of them (although I cannot be held responsible if they are off by a mils here or there!)

Electrical:
The only real electrical work I've done so far has been the laser pointer power supply, which is taken straight out of the LM317 datasheet!

Internal Photos:
Click to enlarge - Warning: High Res!