It’s really annoying that the fan on the S9 Laser head is continuously blowing (at full speed) regardless whether the Laser is in use or cooling is needed. As soon as you hit the power button on the S9 the fan howls.
Question is whether there is a GRBL command in Lightburn to de-activate (or spin down) the fan unless the Laser becomes activated? (Or de-power the head in software entirely).
My fear is that the fan is constantly powered without any control options.
Yes. There is no chance of controlling the fan without changing the hardware / cabling. The fan is connected to the laser module board and as soon as this board is powered up, the fan is running. Basically, this is a good thing, because if you would have to remember turning the fan on each time, I guess, many people would forget it sometimes. And the diode will die within minutes of usage. Typical diodes are already driven at the edge of specifications and temperatures above 25°C will already lead to a decrease in lifetime. So it’s not a good idea to make it controllable.
Since you need to tinker anyhow, you can think of different solutions:
But I guess the easiest thing is a good enclosure, then the noise will be reduced to a very low level. And actually, I would recommend to never use such a laser without housing and ventilation anyway.
And another small remark: then don’t upgrade to the S10 module, that one is at least twice as noisy 
Most of these are ‘laser modules’ that control the fan with their own controller on the module.
What you have control of, is dependent on what control lines for the laser are available.
Most have three lines… pwm, power and ground. So no fan control…
My module has 4 connections …
My fan only runs until it is cool then shuts off. As you increase power the module senses it over time and increases the fan speed… I have no control over it…
Thanks for your replies. I actually just purchased the S10 as upgrade to the S9, which I intend to sell, but haven’t unboxed it yet. That much for the noise of the S10.
I guess I have to do some further research on the pinout/wiring: The Sculpfun S9/S10 has a XY DLC v1.0 GRBL Controller Board, which looks somewhat similar – yet not identical – to the Makerbase MKS DLC:
I think the S10 uses a different 32-bit board actually. Can’t remember the specific name but something like XY DLC32.
Not sure I’ve seen anything like this… at least not one provided by Sculpfun. Is there something specific you’re looking for? From what I’ve seen most Atmega328 boards follow fairly closely Arduino Nano based solutions. This one didn’t seem that different.
As you suggest, very similar to MKS DLC.
I see. Will take a look under the S10’s hood then and post a picture of the board here when I find the time.
I’m interested in the schematic to understand what the board is capable of measuring and controlling with regards to the laser head and its attached fan. Whether it’s just a Software issue or actually a hardware limitation that the fan on the Sculpfun S9 (and likely the S10, too) is constantly spinning.
A temperature-controlled fan activation would be perfect. Question is how to enable this, presuming the head provides temperature data to the board. My last straw would be to add an ESP8266 and a temperature sensor/thermisistor and control that annoying fan independent from the GBRL Controller Board.
I don’t believe I’ve seen any facility to read temperature on Nano based boards. And I’m fairly certain the base 8-bit GRBL doesn’t support any concept of temperature although I could be wrong. Additionally, I don’t see any direct way fan signals would be sent with the pins on the laser module for V, S, GND (12V, Signal - PWM, and Ground).
I suspect any fan control logic is likely to be in the board mounted on the laser module itself.
One fact that has me self-doubting myself is that Ortur was able to change the behavior of the fan on the laser module with a firmware update on the controller. Fan used to turn off immediately after laser turned off but a firmware update made the fan stay on for some time to allow for additional cooling. Ortur has the same 3 pins on their laser modules although running a different board and firmware. So, there’s obviously some way that the controller is manipulating the function of the fan. If I had to guess I’d assume that the controller is sending a very low PWM signal to keep the module active but not high enough to fire the laser. But purely speculating.
For the S10 laser module I’m going to assume Sculpfun had a difficult time with heat management and just decided that they would run the fan on full all the time just to be safe.
You could potentially test this by providing the laser module 12V and ground but with no PWM signal attached to see if the fan still runs. That would show that at least the basic function of the fan is controller by the laser module.
Do I get this right: Is the PWM (Pulse Wave Modulator; just to show that I’m aware of the meaning and general function) used to control the laser’s intensity? And your assumption is that a very low PWM signal – to weak for the laser to turn on – is somehow identified by the board on top of the laser head to activate the fan?
Perhaps I should contact Sculpfun and check with their „engineers“ (although I doubt that they have in-house engineers; I bet these are mostly off-the-shelf parts purchased from smaller Chinese suppliers/engineering companies).
Effectively yes. PWM duty cycle determines laser power level. 100% duty cycle is 100% power. 0% duty cycle is 0% power.
This is just a guess as to how Ortur was doing this. Keep in mind that the intention of the PWM signal is not to control fan… it’s to control the laser. I suspect for Ortur laser modules they’re designed to have the fan on anytime the laser is being commanded through PWM. So a hack to control the fan indirectly could be to send a low PWM signal to the module.
Actually, i suspect they do have in-house engineers. At least that are doing some integration engineering even if they do outsource other parts of the work.
There is no official schematic available. Neither the firmware is open source. You can have a look here: Sculpfun S10 - Diode Laser Wiki There I collected most information about the S10. Within the other sections of the page, I describe how you can add limit switches and relay control to that board as well. As you already speculated, the MKS DLC32 was the base of this board. They adapted the layout to the DLC/S9 board, so that the new one is a drop-in replacement.
Since the official firmware is not open source (yet – I’m still discussing with them, but you are right, they don’t develop the core firmware in-house), you can’t integrate additional periphery to the board as it is.
You can change the firmware to FluidNC where you can control all available pins (and most of the free pins are made available on a pin header) which might enable you to integrate your sensors (as long as FluidNC supports that, I don’t know).
Another workaround with the standard firmware would be to use the relay output that is intended to control the air assist to turn on/off the power line of the laser module. Then the module is only turned on if a job is active. Then you could add the laser module control to the start / end Gcodes to make sure it’s running. Just be aware that you can’t use the air-assist-control function of LightBurn anymore.
But again, I think you are working on symptoms instead of curing the cause Just put the laser into an enclosure (where it is supposed to be) and don’t change the behavior of the fan. It is running full speed by intention, and I think you will kill your module very fast if you start tinkering with the fan. You can also just exchange the fan by a more quiet one, which some users did. But really care about the air volume provided, otherwise you will again shorten your diode lifetime very much.
Additional comment: I might not have read your comment correctly. Did you ask for a schematic of the S9 board? The boards of S9 and S10 are acutally different. The S9 is nearly a complete and pin compatible clone of the MKS DLC board. The S10 is a clone with some bigger changes of the MKS DLC32 board. So they are fundamentally different.
Using the S9 board, you can take the grbl firmware and integrate any temperature-control code you like (if you are able to integrate it into the grbl source code base). Using the S10 board, you can’t change the “offical” firmwares yet as I said in my last post. Information on the S9 board is here:
and some more info on other mainboards:
Thank you all again for your comments. Very much appreciated.
I’d like to install the Sculpfun in an enclosure, but I’m currently working from home with very limited space. Most of the time the cutter hangs on the wall in a storage room and is only taken down when needed.
I’ve contacted Sculpfun’s support email and asked if there’s a chance to fix the fan behavior in firmware. Let’s wait and see. Currently I unfortunately don’t have the time to further investigate on this. Perhaps someone else comes up with an easy to implement fix (a physical switch on the fan just is too risky, if forgotten to turn on).
With led lasers this is not the case… although it sounds good.
But keep this in the back of your mind.
The pwm turns the laser on and off, there is nothing in the middle. When the pwm goes high it will lase for that percentage of time during the ‘period’. If it’s 1% pwm it will lase at 100% power for 1% of the time … may be imperceptible to your eye, but it is lasing at 100% power for that 1%.
Even a co2 laser is lasing or it isn’t, there is nothing in between.
I have a Neje 30W and it has a temperature output, however they advise you to ‘ignore it’ in the documentation. Other than the temperature pin, it only has 12V, pwm and ground. It internally controls the fan with/without pwm. When you power it up, it cycles the fan at full speed then turns it off.
@berainlb is probably correct with his speculation they are using the pwm to let the fan run an extended period via the pwm control.
I can see possible issues with this tact… but if it’s working… I wouldn’t complain.
Good luck
From what I remember of Neje behavior their own controllers have a port for the temp sensor. I think I saw that in their own firmware temperature would be monitored and if temperature exceeded a certain threshold the laser would stop and pause during a burn until temperature dropped to an acceptable level. Then burn would resume. As far as I know, sensor data and control is not available on the GRBL firmware.
I also recall one of the laser module adapter boards having a temperature indicator. This can be used with any laser controller.
