Monday, 3 April 2017

Safety Upgrade: adding an air filtered enclosure to a 3D printer

Micro Kossel moving into new home
     After reading the 3Ders.org article on 3D printers with enclosures and filters reducing particle emissions, I decided to relocate and re-house my existing printers for safety's sake. I've moved the Mini Kossel out to my garage workspace for the moment, more on that another time, and the Micro Kossel got a new housing. 

Micro Kossel's new housing with intake fan installed
     Drawing inspiration from the method of refitting a plastic bin with air seals for storing moisture sensitive filament (example video), I went about tracking down a plastic bin deep enough for the Micro Kossel to fit inside. And since the original article mentions using a hepa filter that is rated for filtering hydrocarbons, I tracked down some normally meant for use on a workshop filter mask. 


Hepa Filters and 60mm fan
    Add to that a couple of 60mm fans, a roll of aluminum tape, some stick-on foam weather-stripping, and a couple of printed adaptors to complete the parts list. Tools are a drill with a 2.5inch pocket hole jig/blade, the aluminum tape, a 1/8th inch or 4mm drill bit, and a pair of scissors or cutters for trimming the foam striping to length.


Foam weather-stripping
One of the filters unboxed
     The first step was to put a strip of the foam tape along the rim of the bin, followed by using one of the fans to mark out where to drill the holes in the sides. After doing that, I measured the dimensions of the filter and designed a printable mounting bracket to interface it with the exhaust fan.


Foam seal installed on bin with spare parts in background
Filter mount on the exhaust fan
Filter retainer ring
    The STLs are available here, they will probably only work with that specific brand of filter, but should be a useful reference regardless. While that was printing, I used the pocket hole bit to make openings for both the input and output fans.


Fan mounting hole with points for screws drilled out.
    After the holes were drilled, it was a simple matter to bolt the fans into place with some spare #6 screws that I had leftover from building the MPCNC, although M4 screws would probably work just as well.

Filter installed and secured with aluminum tape
    For securing the fans, I had planned to use elastic bands to hold the retainers in place, but remembered that I had some Aluminum tape left over from another project, and since it's normally used for sealing holes in air ducts, I decided that wrapping the joints with some couldn't go amiss. 

Power lines for the fans
    Finally, it's just a matter of wiring up the power to the fans. I've got the Micro Kossel fitted with a 2.1mm barrel jack for power, so I just got a couple of spare connectors and created an in-line patch cable that basically just hooks the fans in parallel with the printer itself, turn the printer on and the fans come up automatically.

Post a Comment