MakerBot Print is our newest print-prepration software, which supports native CAD files and STL assemblies,
allows you to interact with all your printers via the Cloud, and many other exciting new features.

Download Now


Mounting plate for Biqu 3D printer hot bed mosfet.

by reactron Mar 17, 2018
Download All Files

Thing Apps Enabled

Please Login to Comment

Hi Reactron, and thanks for the design. I've bought the same mosfet too, but since i'm pretty new around i'm freaking out on how to wire it -expecially for the 4 pin connector- without ending up burning the entire place down. Could you provide me the wiring scheme?

I'm fairly certain that I got my info from this video :


The only thing I can add to what you see in the video is to be aware that polarity is important on the power wires. The signal wires just go where the power wires used to be on the motherboard and the wires to the bed go where the video shows. Don't be confused by the multitude of wires on the power terminals - I did mine that way to jump 12vdc power to my control board input power - your setup may be different, so you may or may not need jumpers between the mosfet and your control board. Also - I didn't use the typical red and black wiring for the 12vdc power - in the pictures above, the gray wire is 12v+ and the green wire is DC ground (-). In the US, those wires are usually color coded red and black, respectively. I think in Europe, the typical wire colors would be solid blue for positive, and blue with a white stripe for negative.

Thanks for your reply,
i may have been a little too generic: i have the same board as you do (GT2560, right?), same mosfet. My concerns were about connecting the 4 pin, if i had to strip out a pair of wires (since, as you may imagine, my PSU has two 12v outputs). As far as i can see (and understand from a total-goofy point of view) is that you connected in series the mosfet and the board using just one 12v line. What about the other one? Does it work fine as you wired it? Are you secretly hiding some kind of alien tech to power up the board? (:P) I figured out how to wire the control & the heatbed, it's that 4 pin connector that baffles me, since most of the tutorials i found on youtube are made on boards that require just a pair of wires instead of the 4 pin.

(Thank you again and please forgive me for my crappy english)

I think you are referring to the power wiring for the GT2560 - It's been a while since I did the wiring, but I recall that the GT2560 has two potential power sources. I think that one of them is for the board's logic and motor control and the other is for the high-current outputs (hot-end and bed). Using two separate power supplies is optional, but not required. You are correct, that I wired the mosfet and the board in series on a single power loop from the power supply. It works just fine - there is no need to run separate loops to each device, although there would be nothing wrong with doing it that way. I suppose that if you wanted to be extra careful, you could have separate runs each with their own fuses. In my setup, I have a single fuse that goes on the AC side of the power supply.

Hi reactron, I just upgraded my Prusa i3 with the same board.
I am curious, why did you decided to install the additional Bed MOS?
I don't have much print time with the new GT2560 board, but so far it has been working good.

Hi Guntars - the external mosfet is probably overkill, especially considering that I'm upgrading an MP Mini with a 120x120 bed.
I did that for two reasons - I already had the part, and I wanted to future proof the control box in case I use it on something bigger
than the Mini. Also, I've read that it's just a good safety measure for protecting the main board - if anything is gonna go up in smoke, it's the
hotbed fet. Cheers!