A couple weeks ago some of our forum members were talking about using a shutter system for their DLP setups. Using a shutter would prevent extra light from being emitted toward the build area when printing isn’t taking place, and in-between projected layers during printing. Some resins are so sensitive to light that this process is actually necessary. This is done most simply with a hobby servo and something to act as the shutter material. Preferably something that can block light very well. In our case we laser cut some acrylic, we also engraved an area deeply so that the servo output hub would grip the acrylic very well.
Then when installed, the shutter is moved into the path of the projected light by the servo and the light is effectively blacked out. When printing, the shutter is moved away from the light path for the short periods of time when curing is wanted, then back in when the layer print time is met. The servo is very easily attached with a small double sided foam tab, that way it can be placed exactly where needed. It should also be easily removed in the future. We’ve already moved ours a few times and it wasn’t a problem.
The next step is to test and to test some more. Once we have a good servo picked out we’ll get a kit into our store. This one should be a pretty low cost upgrade.