Clicking/tapping sound after fan shuts off


#1

After every print I get the same noise from my Glowforge Pro. It’s a tapping / clicking sound that occurs after every print is over and the fan turns off.

Is this normal?


#2

Yes.


#3

Out of curiosity, any idea what’s making that sound?


#4

No idea. But mine’s been doing it for seven months. Maybe something powering down.
:slightly_smiling_face:


#5

agreed mine does this as well


#6

It sounds like the stepper motors are going through a canned position routine at the end.


#7

It is normal and I believe it is the Peltier cooler coming back to room temperature.

Since it has a temperature difference of cold on one side and hot on the other, you are hearing the evening out of those temps.


#8

I like it, it has a rythm similar to crickets talking :slight_smile:


#9

Thermal shock isn’t good for them, perhaps it should ramp the power down.


#10

It happens on Basics which have no Peltiers so I’d bet it’s something with the steppers.


#11

It seems too consistent to be cooling… but I have no idea


#12

Too focused on Pro versus Basic to notice that it is happening with the Basic models also.

From sticking my head in the GF :glowforge:, I hear it mostly in the area of the heat sink.


#13

UPDATE:

It is the laser head that is doing the clicking. Because it parks near the fan/Peltier, it sounds like something is cooling down.

UPDATE 2:

Put my fingers on the head after the cool down warning in the GFUI and can feel the internals on the laser head causing the clicking.


#14

Huh… Isn’t it the same noise that the head camera makes at start up when it’s focusing?


#15

Have heard it called the “Shave and a haircut” dance because of the repeatable beat.


#16

I think so – sounds about the same to me.


#17

That could be what it is doing… cycling the power on and off to it. (I haven’t dealt with peltier coolers in the past though, so not sure if a typical temp controller would be ok for them.)


#18

They recommend high frequency PWM as low frequency can cause thermal fatigue.


#19

Not Peltier unless you are talking about a different sound than the rest of us. Happens in the Basics which do not have the active coolers.


#20

Ya. I saw that after I replied :slight_smile: But was also curious what the ‘standard’ thing to do with a peltier is.