How I repaired by Form 1+ with a second-hand part, some acetone, and a pack of Sugru


A little over a month ago, the unthinkable happened - my Form 1+ broke down. Long story, short - I bought a Form 2 to do my day-to-day business. However, I wasn’t keen to pay the 900 euros to have the 1+ repaired. Especially when I had diagnosed the fault down to a broken y-axis galvo.

Enter @DavidRosenfeld: a gentleman who saw my plight and offered to sell me his spare galvo for a pittance, just to see what would happen. His was an x-axis galvo, but I thought, “let’s give it a try”.

For those of you that don’t know, here’s what the galvos look like:

So, I changed my faulty galvo for David’s, ran it up, and… nothing. I investigated further and found that the difference between the x and y axis parts is the little mirrors on the end - this is the original (broken):
and this is the replacement:

I think we can all see the problem here. This is the point where I thought “screw it” and bathed both the mirrors in a jar of acetone:

this dissolved the glue holding the little mirrors in place. With this done, I glued the old mirror onto the new galvo.

I then set about calibrating the galvos. I got the method from this guy:

Essentially, what you need to do is create a cross pattern, centered on your build plate, like this:

And match a centered cross on a spare resin tray:

Then, you just run the print, gently turning the galvos by hand until you get a result like this:Calibration

The next problem was that I couldn’t tighten the holding socket for the galvo without it shorting out the galvo. I don’t know if I’d shifted something in the part with all the transportation, etc. or if it was of a genuinely different part that wasn’t designed to be tightened in that area. Either way, I couldn’t tighten it without shorting the printer, and I couldn’t leave it loose and print.

Enter Sugru:

I left this for 24 hours to harden, and tried my first test print with an earring model:

I used a 3rd party resin I had handy, and this was the result:

Would I now trust this printer with my livelihood? No, probably not. But for a small cost, I have a working backup, and a very happy 13 year-old who now has a 3D printer in his bedroom!


As far as I know, you will never get very good tolerances with a manually calibrated galvo. But hey, who needs perfect right? as long as you print parts that works for your needs. Congratulations! have fun with your freshly revived printer! :ok_hand:


One time I was cleaning some dust off my f!+ and when I was taking the galvo block off I got interrupted and loosened the wrong screws which threw the center off. I made a tall tiny cylinder and loaded the file in Preform then hit the print menu. tweaked the galvos until they were back on center. Parts come out pretty much dead on so guess I was lucky.


I just got a used Form-1+ which was sold as not working, and I can see a galvo is missing the mirror. I checked the links on some Form-1 page that discussed sources for spare parts, and the links are dead. I am looking for the Y-axis galvo if anyone wants to sell one. Thank you.