I have a similar use case, I want to power a small 24V fan for my own in-chamber filtration system. Does anyone know how to get power to this connector (or the other 4 pin one on the back)?
It seems you need to turn on a switch in some code within a Fluidd web page setting. I previously forgot in which post I saw someone screenshot this part of the code.
I have modified the configuration myself, changing the enable pin from input detection to a forced output of 0/1 to turn on the 24V power.
Although everything is working fine for now, I am not yet certain about the risks involved. Below is the modified code.
Although this eliminates the need for an additional pulldown resistor, I do not fully understand the actual circuit design; I am merely speculating that the 24V is controlled by a certain MOSFET, and PE15 is the MCU pin that opens/closes this MOSFET. If my speculation is incorrect, I will immediately revert my tentative modifications.
If you have a more technical question, organize the key details so I can ask the hardware engineer directly for the answer you need.
You left out the best top cover I’ve seen!
I immediately installed my own as soon as I saw it while I wait for the official top cover. 
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I contacted support and asked them to confirm that your added lines for ’output_pin’ are indeed putting the 24 V on without side effects. They confirmed that this is correct. However, now that I look again at your changes: why did you put the section {purifier] as remarks? Does you code clash with it?
Thank you for helping me confirm the ‘output_pin’ issue.
I temporarily commented out the ‘purifier’ section since the PWM isn’t working yet. I’m currently using an STM32 board (24V in, 3.3V PWM out) to control the fan so I can at least use the DIY purifier in the meantime."
I’m using a button with an integrated LED to toggle the PWM duty cycles. This allows me to visually monitor the fan speed directly through the brightness of the button’s LED.
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Thank you for this information!
This is very helpful.
Is it possible to tell us the purpose and use of the FLAG and FLAG2 pins in the top cover connector?
How does the printer firmware use or interpret these pins?
Thank you for supporting us with technical details and encouraging community improvements and designs!
I’m also interested in FLAG and FLAG2. I’d like to install both a Purifier Filter (as mentioned above) and a case heater in my DIY enclosure. For controlling the case heater, I’m still looking for ideas on how to manage the control and connection.
Best regards, MarkM
@Rossero I really like your redesign! Much simpler with only 4 pieces!
I hope you don’t mind, but I took some time to add my idea to it!
I added an option to support the use of a vent tube directly into the left rear corner of the mount.
This is to allow the option of venting the fumes from the printer outside or to an external fume extractor.
There is also a cover plate to cover the vent for when you don’t want to use the vent.
I want to add a fan powered vent tube that can expel fumes outside or to a fume extractor filter. However, I wanted the infamous SAMLA cover to be easily removed. Therefore, I decided not to cut into the SAMLA cover to add a vent tube or vent fan.
Additionally, the tube adapter is easily removed and replaced with a vent cover.
Unfortunately, I can’t upload my U1 3MF file here or I would have included it.
I haven’t test printed this yet. Unfortunately, I don’t yet have time to do this and won’t have time to work on this further for a week or more.
Since I haven’t personally printed and tested this yet, I haven’t checked all the dimensions and fitment on the actual printer yet, therefore I’m a bit hesitant to provide the .3MF file, so perhaps it’s a good thing that I can’t upload 3MF files here!
I think it will clear the rear spool of filament when a spool is mounted on the U1’s filament holder, but this needs to be checked and confirmed.
Note that the vent tube can be slid into place, there is a mounting tab to add a heated insert so you can use a 3 mm screw to secure it in place.
After looking at these uploaded photos, perhaps I should have the vent cut into both rear corners, then a user can choose to have the vent on either side and provide optional printable vent tube mounts (left or right). I simply randomly chose the left rear corner for the location of the vent tube.
This photo shows the vent in the side of the left rear corner.
This photo shows it with the vent tube (the extra cover plate in the background).
This second photo shows it without the vent tube,but shows the vent cover plate in the background.
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I think I’ve understood the PIN assignment, but has anyone already implemented this for a build chamber heater? The original top cover has one too.
Here are the questions I have:
- What would the code in printer.cfg look like?
- With what code could I control the build chamber heater relative to the build chamber temperature?
- The 24V PIN output only provides 0.9 A, which is just 21.6 watts. That’s very little for a heater. Would it be better to use a 220V heater and switch it via the 24V? In the original top cover, I don’t see an extra 220V cable.
Thanks for your comments.
Best regards, MarkM
If by “original top cover” you mean the Snapmaker unit, a heater is not in the specification.
I don’t think the U1 is designed with active chamber heating in mind, it would be necessary to ensure all the internal parts are designed to operate at elevated temperature and the control electronics are insulated from the chamber.
That is not to say people can’t play with it, just beware!
with original I mean the original Snapmaker Top Cover, which will come end of year…
Hi! Thanks for sharing this awesome mod.
My main goal is to protect the printer from my cats and keep hair out of the linear rails, so the top enclosure needs to be on at all times. However, for now, I will be printing exclusively with PLA and PETG, so I am very worried about heat creep and trapping too much warm air inside.
Would it be possible for you to upload a dual-vent version with openings on both the left and right sides to allow for proper cross-ventilation?
My plan is that, if the enclosure gets too hot while printing PLA even with the passive dual-ventilation, I can easily attach a USB fan to the duct to actively pull the hot air out, using the other side as a fresh air intake. This way I can keep the inside protected from the cats while keeping the temperature perfectly safe for PLA.
Thanks to you and all the modders involved for making this design better and better!
I need to do some more wirk on this.
I will look into having the vent on both sides, but I don’t think it’s needed to prevent heat creep. However, i havn’t done any teats to confirm this.
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