VzBot CPAP Muffler Adapter for WS7040 Fan Shelf Mount

Created this adapter for the VzBot CPAP muffler as I was experimenting with controlling the noise from my printer. I had already remixed and installed a modified mount for Dan Cernogorsky's CPAP box but wanted to try the CPAP muffler, so this is a fairly straightforward remix of the existing shelf vent piece to interface with the CPAP silencer's airbox. The rest of the muffler parts are printed normally and are available from the VzBot 235 GitHub.

After testing, I found that it eliminating basically all of the airflow noise from the fan box itself, the only remaining noise I could hear was from the cooling duct on the print head, and without a noticeable effect on airflow, so I found it quite effective in silencing one of the main sources of noise.

Printing tips

There isn't really a great way to avoid supports on this print, but luckily the rough surfaces should not be visible once installed. You may print it in either orientation but I found the support material was easier to remove when printed as oriented in the model file.

There are two versions, as I found that the flanges on my shelf vent were a few millimeters too high when using the printed attenuator, so I made a shorter version. The tall version is a direct conversion of the existing shelf vent at the same height. The box is offset to clear the belt path on my printer.

I printed the test piece in PLA and as long as the box is far enough from any heat sources that should be fine. I reprinted it in CF PETG to match the rest of my printer and printed the final airbox in TPU just to increase its vibration damping characteristics, though I can't really confirm whether it performs better than standard PLA.

Modified the shelf vent to match the mounting points for the VzBot CPAP silencer airbox.