CR-10 Silent: New fans, vibration dampers and design upgrades

I recently bought a Creality CR-10-S4 3D printer and one of my first priorities was to make the machine silent so I could work in the same room as the printer. This work included installation of vibration dampers on the stepper motors, changing stock fans and redesigning certain components on the CR-10.  There are several things you can do to make a 3D printer more silent, and it varies from printer to printer. For the CR-10, it will vary from machine to machine as well. After reading forum posts, blogs and facebook groups itˋs clear that the machines are sent out from the factory with different components and noise sources. My biggest priority was to change the hotend fan, it had the noise of a horrible vacuum cleaner, but others reported the power supply fan as the worst noise source. So, identify YOUR noise sources.

Noise sources I have identified and improved

• Noise from stepper motor vibrations transmitted to the printer frame
  • X and Y axis steppermotors.
  • Extruder stepper motor.
• Noise from fan (fan motor, bearings and general fan design)
  • Hotend fan (40x10mm).
  • Control box motherboard fan (50mm).
  • Control box exhaust fan (40x20mm).
  • PSU fan (60mm).
• Noise from the air being moved, passing obstacles, turbulence
  • The hotend fan cover could need a better design to guide the air.
  • The control box exhaust fan is mounted onto threaded inserts in the control box chassis that stick out approx 5mm, which leaves an airgap between the fan an the chassis. Next, the chassis is cutout to look like a fan grill, but the openings are very very small and poorly designed for the amount of air passing by. Also, the circular hole is actually smaller than the fan.
  • The PSU fan wins the first price for stupid design and assembly. It’s protected behind the PSU chassis cover with a fan grill design. On top of this cover is another cover, the control box cover, also with a fan grill design, though with unmatching design. Fully assembled the fan has less than 20% air opening combined in the covers! Dragging air through this makes noise.

Noise sources identified, but not improved

• The control box motherboard fan is sucking air from between the display cables and blowing air directly onto a bunch of other cables.
• Noise from stepper motor vibrations caused by stepper driver type
• Noise from filament cooling fan (the radial fan next to the hotend)
  • I’ll leave this one for now. It doesn’t seem to make much noise.
• Noise from both Z axis stepper motors transmitted to the printer frame
  • The brackets for these steppers makes it a bit difficult to upgrade, and there are less movement in these stepper compared to X and Y axis steppers. However, all steppers are on while printing, even when they are now moving, so some vibrations can be detected.

I ordered stepper dampers and fans on Ebay.

Stepper dampers

My first and simplest step towards silence was mounting stepper dampers on the x and y axis. The stepper motors are mounted in such a way that the vibrations will be transmitted and amplified through to the aluminum frame. The dampers can be mounted in 15 minutes and it really made a big difference! Probably the simplest and most significant noise reduction you can do on a CR-10.

CR-10 Stepper Damper: This is the Y axis stepper motor with the vibration damper mounted. This was a very easy swap, all the same M3 screws could be used again. The pulley was adjusted according to the increased damper depth by loosening the grub screws on the pulley.

CR-10 Stepper Damper: This is the X axis stepper motor with damper mounted. When using stepper dampers only two screws hold the motor, and here one of the brass stand off became obsolete. The pulley was also adjusted just as with the Y axis.

CR-10 Stepper Damper: This is the extruder stepper motor with damper mounted. This was a bit more technical than the two other axis, as the lever and spring had to be dismantled to get to all the M3 screws and one screw also had to be changed and a nut added, as can be seen in the picture.

Installing a stepper damper on the extruder isn’t strictly necessary, and some may argue the motor doesn’t move enough to create much vibration noise, but I had extra dampers and gave it a go.

The Z axis stepper motors are not moving much compared to X and Y and are generally not considered a damper target. Furthermore the stock CR-10 Z axis stepper mount isn’t damper friendly as the stepper motors are held in place by two M3 screws on the same side. A new mount could be designed to fixed this, but for now I’ll leave it as is.

The CR-10 used to be like having a heavy duty industrial machine in the house and you could easily hear it in nearby rooms. With the dampers mounted it became more like what a 3D printer should be.

What fans to buy

I decided to change the hotend fan, the two control box fans and the fan in the power supply. I wanted silent fans with good CFM (cubic feet per minute) at a reasonable price. I read through quietpc.com overview of fans and found that Gelid Silent was the reasonable choice, for 40, 50 and 60mm sizes. I ordered the fans from Ebay. I also ordered an additional 40x40x20 nobrand “silent” fan for the control box exhaust just in case the gelid one would be too weak. After a couple of weeks I received the fans.

• Case fan comparisons: https://www.quietpc.com/casefans
• Further information about Gelid Silent fans: http://gelidsolutions.com/product-category/thermal-solutions/case-fan/silent-case-fan/

Other brands of silent fans can also be used. Noctua or Noiseblocker are maybe the most known silent fans in the market, but a bit more pricey. Before you choose a new fan, examine why the fans are where they are, what components they are supposed to cool and how they do it. In this blog post you will see how I swap out fans for lower CFM (cubic feet per minute) fans, but only after surrounding conditions are changed.

It works for me, use your own reason.

 

The hot end fan

I started the fan swap modification with the hot end fan. There are reports of several people having trouble with stuck nozzle because of the Gelid Silent 40 CFM performance is too weak and it doesn’t cool the hotend enough. I have not experienced stuck nozzle after changing to Gelid Silent 40, but the fan is dead silent compared to the stock fan. However, the Gelid Silent 40 does indeed have significant lower CFM than the stock fan, so if you are worried about it keep searching for fans.

To connect the new fan to the hotend I had to cut the old fan off and solder on new connection points. I find the JST connector simple to use.

The fan housing was my next target. I absolutely hate the fan grills that interrupt air flow and the whole fan house design looked only like a bracket for the fans. It does not look like the Creality design engineer had air flow and cooling in mind. Off course, in my opinion the whole X gantry trolley the hotend is mounted on should be designed differently if optimal airflow was to be achieved. Oh well.

I took measurements and designed a new one in Fusion 360 and printed it.

This was my first fan housing design test. It was designed to look like the stock metal fan housing, but with the fan mounted on the outside.

I wanted to keep the stock nozzle fan on the side, so I focused my design efforts on a retrofit fan bracket that would direct air unobstructed to the hot end and away. The Gelid Silent 40 is mounted on the outside of the housing, for simple maintenance.

The solution wasn’t optimal so I designed a new one. This new fan housing design can be downloaded from Thingiverse.com, see links at the bottom of this blog post.

I designed the housing to allow for good airflow to the heat sink and away from it. Placing the fan above the hotend makes it easier to see the nozzle while printing.

The stock radial fan is kept, for now. Mounted in the same position as the stock fan housing.

Fang design? As per now I don’t see the point as my designs are coming out okay. Over time I may consider a fang design for better airflow from both sides, but this depends on what I’ll print in the future.

The control box fan

This fan is 50mm and is mounted onto a metal bracket. As usual on the CR-10 the airflow is obstructed, and this time the fan is placed right in front of a bunch of cables. Although it’s possible to design a bracket that can hold the fan in a better position this isn’t a priority. I’m swapping out the stock fan with a Gelid Silent 50.

The Gelid Silent 5 was easily installed on the bracket inside the control box.

Before installing the fans in the control box, a JST XH 2.5 connector must be soldered on.

The control box exhaust fan

The stock fan is a 40x40mm and 20mm thick fan. It isn’t actually very noisy. But everything around it is the problem. First, the fan grill in the enclosure is obstructing air flow as if it was a functional requirement. Second, the threaded inserts in the control box chassis is sticking out 5 mm on the inside and creating a big air gap between the fan and the inner wall. And the diameter of the exhaust hole itself is actually smaller than the fan.

I wanted to swap the 40x40x20 fan with a Gelid Silent 4. As with the hotend fan, air flow can be a challenge here. But instead of having strong fans pulling air through small restricted openings I can use this smaller fan if I open up the air flow into the enclosure.

I modified the chassis by removing the grill design. I drilled small holes in the grill and used small pliers to pry it off.  Using the stock fan with this hole in the chassis already lowered the air flow noise. But the air gap still annoyed me and it was obvious noise could still be lowered.

To make it easier to get the fan grill off I drilled small holes in the four corners.

With pliers the fan grill can be taken off. The edges in the remaining hole will need grinding and sanding to obtain a smooth circular opening.

I designed a “fan funnel” that I could mount between the fan and the threaded inserts on the inside. This funnel then acts like an extension of the fan, guiding the airflow out. The air gap is then eliminated. The 3D model can be downloaded from thingiverse.com using the links below in this blog post.

Using a thinner fan, new shorter M3 bolts was needed. The fan funnel has a simple design.

The Gelid Silent 4 mounted with the fan funnel.

It’s easy to see the gap when the funnel is printed in white PLA. With the fan funnel the air goes straight out from the fan and out of the enclosure.

The fan funnel could certainly be designed with a shorter funnel, but I tried to find information about flow and turbulence characteristics and with the little data I could gather settled on a pipe ending away from the enclosure wall. By stopping the 3D print process early, the fan funnel will be shorter.

 

The PSU fan

As mentioned earlier in this blog post, the PSU fan wins the first price for stupid design and assembly. This becomes obvious when you turn the control box over and look at the bottom cover. A cover over a cover etc. With obstacles like that a strong (and noisy) fan may be needed yes – or just remove the obstacles.

The stock CR-10 setup: The 60mm fan is mounted beneath the stainless steel fan grill. Then the black bottom cover is put on top of that. And the black rubber feet of 10-12mm provides clearance between table and bottom of control enclosure.

After some thinking about how I should make life easier for the fan I decided that I could design a complete new bottom plate for both the PSU and the control box combined.

I designed the enclosure to cover the extents of the control box.  I use the Gelid Silent 6 fan for the PSU. The rubber feet can be screwed into the PLA (or whatever material is chosen for printing).

I added holes for additional airflow in the front (the four hexagonal holes) so that the suction of air into the control box became easier. I hope this will help both fans in the control box (motherboard fan and enclosure exhaust fan).

PSU air flow holes

The large copper wire wrapped donut visible inside is a toroid core inductor that will get hot when the PSU is on. Especially when the heated bed is set to a high temperature over a longer period of time. Inside of this component is a temperature switch, also visible with to black wires attached, which will control the 60mm PSU fan. When the component reach a set temperature the fan will turn on to enable cool air to flow by.

I designed this cover with additional holes for airflow around the toroid core inductor, but overall kept the rest of the design as-is in case of existing airflow engineering (but I doubt there are much to it). The PSU have additional holes in its main enclosure, but some of these are obstructed when mounted into the CR-10 control box.

With this solution the fan can run with minimal efforts and new fresh air can cool the hot components. The 3D model can be downloaded from thingiverse.com using the links below.

Parts on Thingiverse

I have made the parts available on thingiverse.com

• hotend fan cover
• control box fan funnel
• PSU cover

Please visit https://www.thingiverse.com/thing:2783408 to download the STL parts.

 

If you have gotten this far down the blog post something must have poked your interest. I’d love to hear what you think about it, check out the comment section or the contact link   🙂