I tested noise and heat insulation, so you don’t have to
I tried to reduce Core One noise by insulating the panels with foam tape. With the added benefit of heat insulation. I removed all panels (sides, acrylic sheets, top, and back) and applied 1 mm thick, 10 mm wide EVA foam tape to the frame, avoiding the rivet holes. This created a foam layer between all the panels and the frame.
Noise
I prepared this noisy star model for testing. It prints at up to 350 mm/s with various combinations of X and Y movements and angles.
The printer is placed on a 40 x 40 x 4 cm concrete paver weighing 14 kg, with foam underneath. This setup effectively dampens vibrations and noise, as demonstrated in CNC Kitchen's tests.
I measured noise levels using a phone app. Not a precise instrument, but sufficient for detecting relative changes. Measurements were taken during a few layers of printing, 50 cm from the front and the left side (with an empty panel), in both normal and silent modes, with chamber fans on and off.
Without insulation, the average noise level was 50 dB in normal mode, with peak averages of 57.4 dB. In silent mode, it was 47.7 dB, with peak averages of 55 dB.
With insulation, the average noise level was 50.5 dB in normal mode, with peak averages of 58.3 dB. In silent mode, it was 47.1 dB, with peak averages of 56.1 dB.
Subjectively, the insulated printer sounded a bit like a drum, making the overall experience slightly worse.
Heat
I designed this cover for the hole in the right panel. And conducted some measurements at a room temperature of 25°C. While not a laboratory setup, the results are sufficient for comparing the differences with and without insulation.
For the first test, I lowered the bed to the bottom, set it to 115°C, and waited until the chamber reached 45°C. This took 21 minutes. The result was the same for both the uninsulated and insulated printer.
The second test simulated a more realistic high-temperature printing scenario, where the bed is about 10 mm below the nozzle, heating a smaller airspace before printing. I set it up for ASA printing, increasing the bed temperature to 115°C and setting the minimal chamber temperature to 50°C to ensure more heat before the print head starts moving. Normally, ASA starts printing at 40°C, with the chamber temperature rising to around 55°C during the print. This works fine due to the heat concentration near the bed at the start of printing.
For both the uninsulated and insulated printer, the bed reached 115°C in 6 minutes, with the chamber already at 38°C. It reached 45°C in 12 minutes, and the only difference was at the 50°C mark, where the uninsulated printer took 24 minutes, while the insulated one reached it in 21 minutes. Which would have no effect on printing.
Conclusions
The changes are negligible and not worth the effort.
It definitely doesn’t improve noise. Seems like one does not simply outsmart Prusa engineers with a €2 tape trick. The use of nylon rivets seems like a very smart choice, as nylon dampens vibrations, and the slightly loose attachment helps prevent the drum effect on the panels.
If your printer is in a very cold environment, this upgrade might help with heating. However, the steel frame and panels act as effective heat sinks, so achieving significant results would require additional insulation on their surfaces. A simple expanded polystyrene box around the printer would likely be an easier and more effective solution.
RE: I tested noise and heat insulation, so you don’t have to
Thanks a lot for your work!
I was very curious about doing exactly what you did and it's nice to know - that I shouldn't do it.
I'd be curious about putting acoustic foam on the panels on the outside.
But I guess, as you said, the best solution would be to build a box around it and put whatever you need on the inside or outside of the box. Acoustic foam, thermal insulation etc.
RE: I tested noise and heat insulation, so you don’t have to
For dampening of panel vibrations you need something with mass, like the heavy bitumen mats that you find on sheet steel in machines, on car bodies etc. With the heavy mass of the printer i suspect it might end up worse than my mk3s+Lack enclosure in my workshop that is fairly cold during winter, might need to try either insulation or a chamber heater to help it up to temp.
RE: I tested noise and heat insulation, so you don’t have to
When I suggested foam strips a few weeks ago, I was under the assumption that some of the side panels are rattling against the frame when excited by motor vibrations of the "right" frequency. If rattling is not an issue in your printer and the panels just "hum along", while being firmly coupled to the frame, then the narrow damping strips won't have much effect.
Damping the intrinsic vibrations of the panels themselves would be one option -- either by adding material with mass and viscosity, or by stiffening them with e.g. glued-on profiles to shift their resonant frequencies upward. But that's probably impractical and/or ugly...
I would rather start with aiming to reduce the source of vibrations. Let's hope Prusa figures out how to get the phase stepping calibration to work on the Core One (see the discussion in the VFA thread). And then hope that this will reduce vibrations as effectively as it apparently did in the XL.
RE: I tested noise and heat insulation, so you don’t have to
It's certainly a testament to the community that people are trying to work towards a solution to this.
It would though, be nice once the dust settles (or hopefully before) from all the orders; that Prusa come out with some documentation on the causation and remedies for this.
We're yet to see instances in which this issue is apparent in kits, but we'll find out soon enough, I'm optimistic that it won't, but optimism does not a good printer build. (You can use that quote if you like) 😅
Scott
RE:
Has anyone tried using weighted adhesive backed foam automotive noise insulation (or similar) on any of the large flat sheet metal parts? Flipping through the kit build manual the base plate the Z steppers mount to seems to be an excellent candidate for a thick pad. Might even be able to fit some thin sheets around the insides or just place them in the recesses of the side panels.
As a proof of concept you could slap some big flexible magnet sheets (like for fridge magnet crafts) on the same surface and not get adhesive gunk everywhere.
RE: I tested noise and heat insulation, so you don’t have to
Has anyone tried using weighted adhesive backed foam automotive noise insulation (or similar) on any of the large flat sheet metal parts? Flipping through the kit build manual the base plate the Z steppers mount to seems to be an excellent candidate for a thick pad. Might even be able to fit some thin sheets around the insides or just place them in the recesses of the side panels.
The base plate is not sheet metal, but thicker steel. It weighs 2.8 kg on its own. I don't think it is a likely candidate for resonances.
On the side and back panels, I would hate to put foam on the outsides, considering the looks and the ability to clean the surfaces. And on the insides there is very limited room for padding.
My kit-built Core One does not exhibit any panel resonances. The dominant noise sources are the chamber fans when printing PLA in Structural mode, and the motors and Y bearings when printing faster. If other printers show panel rattling at specific resonant frequencies, I would hope it is possible to track them down by touching the individual panels during the print. Then eliminate the rattle in a targeted way, e.g. by tightening screws or taking the panel off and giving it a slight pre-bend to tension it against the screw or rivet mounts.
RE: I tested noise and heat insulation, so you don’t have to
Noise also comes from the Y-axis linear bearings and the X-axis linear rail. I think automotive sound-deadening sheets could help if applied around the XY gantry area - on the top of the side panels, the side acrylic sheets, the back panel, and the top panel.