In the recent MK3 review, I compared the heat up times of both the Prusa MK3 and MK2, and
you might have noticed that small annotation I had with the MK2 being overvolted.
A while ago, I had already published a video on how to do that and have your printer, any
printer, really, heat up way faster and reach higher temperatures, but I pulled the video
shortly after because it didn’t really have all the appropriate warnings attached to it.
So before we start:
DO THIS AT YOUR OWN RISK Ok, are we clear here?
Let’s go.
So the reason you might be doing this mod in the first place is because your printer’s
heaters are just not quite powerful enough for what you want.
That might be the heated bed not quite reaching the temperature you need for PETG or ABS,
or it simply not being fast enough to get there - something like the CR-10 actually
takes like 30 minutes to heat up to 70°C, and even that is borderline too cold for PETG.
On the early MK2 printers, the part cooling fan was too powerful to keep the hotend at
temperature - that’s fixed on the newer ones, and of course, the MK3, but it could
still be something you see on your 3D printer as well.
But whatever your reasoning is, faster heatup times for the heated bed and the hotend are
never a bad thing, right?
So what we’re going to do about that is to increase the power supply output voltage.
This will in turn also drive more current through your heaters, so by just turning the
voltage up 5% from 12 or 24V, you actually get 10% more power at the heater.
It’s super easy to do, and in most cases boosts your heater power quite a bit - what
I’m about to show you on the first-generation MK2 has it output 36% extra power - that means
you can run the fan at full blast, or on something like the CR-10 with a heated bed which is
just borderline powerful enough, you can use higher bed temperatures to print more materials
or just spend less time waiting for your printer to get up to temperature.
As a side effect, having more voltage in your 3D printer also makes the stepper drivers
perform better, especially at higher speeds.
So… let’s get to it!
So first things first as always if you are working on any sort of electrical device turn
of the power and wait a few seconds for everything to discharge inside this mod we are about
to do is also going to work on other machines that use similar styles of power supply but
of course each machine is different in it´s own sort of ways your results might vary for
the Prusa MK2 to remove the power supply from the frame you got the two screws in the back
and these two M4 screws in the front here that hold it to the frame next up you can
remove the protected shroud from the power supply by undoing these three screws this
large one in the back and these two smaller ones in the side once you got those unscrewed
you can slide the powersupply conver off but you dont have to slide it off all the way
you just need to get it off far enough to expose the small hole in the top of the cover
right there that hole lets you access the potesiometer that in turn adjust the output
voltage of the entire power supply to adjust it you need to carefully reach in there with
a flat head or a philips screwdriver making sure not to touch any of the components around
it and by turning it clockwise you can increase the output voltage of the power supply this
one goes to around 13.7 volts but others goes over 14 or a bit lower if you dont want the
full effect of this mod because your powersupply is at its limits already or you have electronics
that may not handle the extra current simply dont turn it up that far or back off a bit
one you reach the maximum my Prusa printers the maximum position works prittey well though
as I like to say reassembly is the revers of disassembly so yeah do that once you get
everything assembled again keep an eye on the power supply for a while to make sure that
it stays cool to the touch and altso maybe check on the electronics after a few minutes
of printing just make sure that the output transistors are not getting to hot one other
issue you might be running into is PID tuning of the heated bed and the hotend however we
havent changed the output power to much so your old PID values if they where well tuned
will usually still work but ofcourse you can always retune them and I've got an ancient
video showing you how to do exactly that right up here and thats the entireley of the
mod if this video helped you out by making your printer heat up a bit faster and hopefully
didn't damage to much give the video a like get subscribed if you want to see more like
it and if you really enjoyed it maybe consider supporting this cannel on Patreon thanks for
wathing and I will see you in the next one