Form 1+ laser spot flare issue and a possible solution

Hi Guys, i have been experiencing the same old issue with the laser flaring and causing surrounding resin to get saturated and prints to fail. I think i found a solution on which i am going to work on for my next project and that is finding a suitable replacement laser unit that i can retrofit onto the Form 1+.

I recieved the actual laser and did a few tests, and the laser spot is by what i have seen perfect :confused:
I got a 250mW 405um laser module with a drive board that allows adjustment of the laser powe output from ~0-250mW so it can be calibrated to whatever output we need to match our settings.
This was my laser spot, tomorrow i will try and take a pic in simmilar conditions with the new laser.
It is focused so im curious to see if that system will work, but from what i’ve been reading - so is the current laser unit in the Form 1+ so in the worst case scenario it could be a matter of replacing the diode in the original housing + optics :confused:
What do you guys think?

From my recollection, Form1+ laser module has a photodiode built in, which it uses to calibrate the power before each print. The value was even, IIRC, exposed in the debug logs. Without the signal from the diode, it might not allow you to start printing at all.

Well that’s great, should be less tinkering then. I was thinking of hooking up the laser with a power output set to somewhere near 150mw, and letting the calibration system take it from there, if there are small issues i can always tweak the base power and see if that has any effect, but i think that for the output power to vary the driver simply varies the output current, so an already clamped output shouldn’t be an issue. The thing i am worried about is the laser focal point and if the optics are simmilar. But then again, it might be easier to simply put the replacement diode in the old housing, right?

HI Therion_339

Did you buy the laser from formlabs?
Can you tell me how much you paid?


Hello, no i got it used for 1000e. Got 2 build plates, 6 resin tanks and about 500ml of Tough resin with it. Why do you ask?

I might be misremembering, but i think the photodiode is in the laser assembly. As in, part of the module.

yes it is.

I’m not sure because i still haven’t taken it apart, but i think it should be press fit into the aluminum housing. Removig it usualy damages the old diode, but that depends on the tolerances used when machining the housing. I’ll record the whole thing, but i’m confident it will work fine :slight_smile:

This topic was automatically closed 15 days after the last reply. New replies are no longer allowed.