Build Your Own SLA/SLS

Hi,

I'm currently building my first SLA printer.

For this I got a Optoma HD70 DLP projector with a broken color wheel. Unmodded I was not able to cure FTD standard resin in a good time (>20-30 seconds per layer). So I decided to remove the UV filter.

After the removal the projector shuts itself down after approx. 5 minutes and it reports a lamp failure. The temp led is off, so it seems it's not a temperature issue (at least at the location of the temp sensor).

I've already searched a lot, but I was not able to find a solution for this.

Thanks in advance for your help and tips.

After inserting the UV filter back again the issue persists, so it seems it is not caused by the UV filter. After searching a lot I found some reports that the lamp driver board is often failing on this projector, the only solution I've found so far is to replace it. But there is no shop were I could buy a new driver board.

This evening I want to try to bypass the check between the lamp driver and mainbaord. There is a 5-wire connector from driver to mb, directly behind this connector there are 3 optocouplers, so it should be easy to figure out which one is responsible for the "lamp ok" signal.

Is it possible to exchange the bulb with an UV led (already found some 5W with 365nm or 395nm wavelength). If yes, is 5W enough?

I've found the cause. It was not the lamp driver.

The color wheel has a small opto unit near it to control the color wheel. There was a lot of dust on this opical sensor, after removing the dust the projector is working fine again.