5
$\begingroup$

On a budget, I'm water-cooling a 3D printer. I'm using a 5 V aquarium pump (\$3). Originally I tried to only use about as much water in a can of chickpeas but then found out i needed a lot more. I have a deliberate need to water cool stepper motors in the first printer, so that I can print with a high temperature filament like PEI (the operating temp of a stepper is maxed at about 53 degrees celsius; PEI requires an enclosure temperature of 80 °C), but on another printer I'm having some other issues with the motors that I think could be solved by better heat dissipation.

What I am getting to is a device like this:

e

It is the perfect size for a stepper motor. My plan is to zip-tie one of these to each stepper motor and water cool it in a single path across my printer, including the hot end.

Can anyone think of a reason why this wouldn't work? i just haven't heard of anyone doing anything like this, but it makes sense to me as a chemistry minor. The specific heat of water is way higher than almost anything else. And it is way less noisy than fans. And it works inside an enclosure, while fans might not

Should I ziptie the aluminum block to the back part of the stepper where the metal is, or to one of the darker black sides?

Would I be able to 3D print a cooling block like this instead of paying for it? See also this relevant question on thermal conductivity of various 3D printing filaments. It should probably be metal to transfer heat better?

$\endgroup$
  • 3
    $\begingroup$ Why are you convinced you need to water cool the steppers? $\endgroup$ – R.. GitHub STOP HELPING ICE Aug 27 '19 at 18:09
  • $\begingroup$ Well, for high temp printing (e.g. PEI with 350 deg C extrusion), I def have to. The operating temp of a stepper is maxed at about 53 degrees celsius. PEI recommends an enclosure temperature of 80 degrees celsius (!). NASA uses a custom air filtration system to cool the steppers, but this seems a lot easier. For this application, I should probably use a tub of water, actually, not a chickpea can. $\endgroup$ – K Mmmm Aug 27 '19 at 18:13
  • $\begingroup$ As for the other issue I briefly mentioned, it is because I have eliminated almost every other possible reason for it. But I dont want to get into it because it would be better as another question $\endgroup$ – K Mmmm Aug 27 '19 at 18:14
  • 4
    $\begingroup$ OK. I suspect it would be better (less catastraophic failure modes) to get the motors all outside the heated enclosure, but that doesn't invalidate the question in any way. $\endgroup$ – R.. GitHub STOP HELPING ICE Aug 27 '19 at 19:32
  • 1
    $\begingroup$ You can print it custom shaped to touch properly also the sides if you use TCpoly filament, but I'm not sure about it being watertight. Also, you will need a radiator. A can will not dissipate heat fast enough and you will end up with warmer and warmer water over long prints. $\endgroup$ – FarO Dec 17 '19 at 11:14
2
$\begingroup$

I just did this lol and checked online to see if anyone else did it too. It works really nice.

I used thermal paste and zipties to secure each block to the stepper motor. Dont use thermal tape its not as effective as paste.

I had to do this operations since my motors were overheating due to the enclosure design.

enter image description here

| improve this answer | |
$\endgroup$
5
$\begingroup$

Cooling any single face of the motor is fine. The motor case conducts heat very well. Many 3d printers effectively cool the motors merely by having the output drive face of the motor bolted to a metal bracket which is bolted to the aluminum extrusion frame. That's it. That contact alone cools the motor, which is shown by how the motors overheat when people install vibration dampers, which puts rubber between the motor and the extrusion.

The only thing I would worry about is the surface area inside this particular style of block, and ensuring that you use an all-aluminum radiator since the block is aluminum.

There is another type of cheap 40x40 aluminum block with the nipples on the face instead of on the edge. That style has fins and a lot of surface area inside. This style with the nipples on the edge has a big S channel inside and not much surface area. It may still be more than enough. I'm just saying it's a significant difference and it might make a difference. If you find you're not cooling enough, all you may need to do is switch to that other style of block, not try to install 3 blocks per motor or any other exotic nonsense.

But no way do you have to worry about coooling more than one face of the motor, nor does it matter rwhich face it is, especially not with active water cooling like this, as long as the block is actually making good thermal contact with the motor (thermal tape, or thermal epoxy, or thermal pad & zip ties)

| improve this answer | |
$\endgroup$
3
$\begingroup$

Your solution will not cool all sides effectively. Firstly don't use zip ties; get thermal tape.

Thermal Tape (https://www.amazon.com/Thermal-Interface-Products-Heat-Sink/dp/B00QSHPH8E/

Secondly, the heat will need to travel around the outside of the motor to get from the side that doesn't have the water block. Its expensive but you could use Pyrolytic Graphite Sheets to wrap around the outside of the motor, to get the heat to the water block faster.

| improve this answer | |
$\endgroup$
  • $\begingroup$ Thanks. Wouldnt Kapton or a similar tape work too? $\endgroup$ – K Mmmm Aug 27 '19 at 18:39
  • 1
    $\begingroup$ For both those issues. It should conduct heat more evenly if it is taped on, and these guys are good at conducting heat i believe. $\endgroup$ – K Mmmm Aug 27 '19 at 19:00
  • 1
    $\begingroup$ No. Kapton tape is no where near as thermally conductive. $\endgroup$ – user77232 Aug 27 '19 at 19:38

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.