With the main structure of the enclosure finished, I still needed to do quite a bit of work to make it fully functional.
First, to make sure that the bed heater wire does not get in the way of the print head/bed, I attached an old badge lanyard I had lying around to the cable to keep some tension on it. This way, as the bed translates in Y, the middle of the wire bundle is lifted upward and out of the way. Something like this should do the trick.
Next, I installed some lights so I didn’t have to use my cell phone flashlight to see what I was printing anymore. I purchased this LED strip from Amazon, cut the correct lengths and spliced them together so that I would have plenty of light. I wired in a switch for easy access, and neatly secured the wires to the walls using these Command Hooks.
Now that I could see what I was printing, I needed a spool holder. Unfortunately, there is no standard filament spool size, as 3D printing blogger, RichRap, has pointed out in his lengthy post on the subject. So my design goal for this spool was to create a universal design, that would allow me to use any size spool I might purchase in the future.
I decided to mount the spool horizontally on the top of the printer, to save desk space. To account for any spool inner diameter, my design uses a 3/8″cap screw to attach a hub to the spool, which then sits in a cradle that is mounted directly to the top surface of the printer. Hexagonal pockets are sized to retain the bolt cap and nut so that the user can spin the hub and tighten while centering to the axis of the spool. With the hub in place, the weight of the spool keeps the spool in place atop the cradle. Three ball bearings (from Amazon) provide low friction axial support, allowing the spool to spin fairly easily as the extruder pulls filament. If in the future, I buy filament with a different spool width, I just need to go down to the local hardware store and buy the correct size! Check out the design files on Thingiverse!
Next, I designed some simple handles to mount to the polycarbonate door to make it easier to take on and off. I used flat head #6 screws and used a countersink bit to make the heads seat flush against the inside surface. I oriented the handles to be printed flat so I wouldn’t risk delaminating the layers when pulling on the handle, however this meant that attaching them with screws could potentially crack the laminations. In order to minimize this, I drilled out the printed pilot holes to just under the diameter of the #6 ( to around 0.13″, slightly larger than an 1/8″ bit).
Pretty quickly after printing my first fan mount for the Prusa i3, I realized that it wasn’t really doing the job well. The fan was actually cooling the extruder too much, and I wasn’t able to get to the correct temperature. My problem wasn’t that the extruder needed cooling, but that print itself needed cooling, so I designed a new fan mount that directed the air a the extruder tip. It is designed to mount to the two original holes, and mounts to this 40mm fan. This fan isn’t very powerful, and the reducer is probably doing a very inefficient job of directing the airflow, so there is room for improvement. However, I can now run the fan, and keep the extruder at 185° C, and there seems to be less stringing than I used to see before the new mount. Click here to download and print the model on Thingiverse!
My last set of tasks was centered around the electronics of the Prusa i3. After installing the printer, everything was just sitting haphazardly in back of the printer.
First, I tackled mounting the display screen. I designed a mount for the board itself, and then a faceplate to shroud the display. For the face plate, I designed it to print vertically, as removing support material from the back of flat surfaces like the face plate is hard to do. To get the square window for the LCD panel, I thinned out a bezel around the screen to the width of one filament (0.35mm in my case), so that I could cut it out later. This was my longest print ever, at 16 hours, and it was really a boost of confidence that the printer is finally becoming a useful tool, instead of a time-wasting frustration generator. You can find the design here on Thingiverse.
The final task was to mount the RAMPS board itself and attach the power supply to the printer. I designed a simple mount for the board, and a multi-piece bracket to hold the ATX power supply. With everything in position, I bundled up the cables to make them nice and neat. Take a look on Thingiverse to download and print them yourself!
And here it is… the final product!
With the enclosure build complete, I have a few summarizing thoughts:
– Building an enclosure has made a huge difference in print quality. The enclosed environment prevents temperature fluctuations from the cool air in my large drafty basement. The heated bed heats the air in the chamber to provide a gentler temperature differential from extruder to part, so that I no longer have to worry about warping, or and over/under heated extruder.
– Hard mounting all of the wiring has reduced printer mishaps. I have always been worried about having the printer catch fire due to a faulty connection. With the power supply and controller wires loose, there was always the possibility that something would come loose and cause an issue during printing. Now, with the power supply rigidly mounted, the wires do not get moved around, increasing reliability of the printer, and enabling longer prints.
– The printer is more pleasant to use. Because of the temperature fluctuation, and potential disconnection worries, printing things used to be a hassle. Now, I can get things printing quicker, and check on them without worrying about errors.
– Soundproofing is hard. The original point of this project was to make the printer quiet enough to enable me to use the printer upstairs in my workspace. Unfortunately, even with the dense 3/4″ MDF walls, the printer is still too loud to sit in the room adjacent to the bedroom. For overnight prints, it would definitely disturb our sleep. However, since the enclosure controls the printing environment, I was able to put the printer in my basement with no issue, which is still pretty convenient.
– One of the major design issues with this enclosure, is the closed back design. The printer is only accessible through the front, making any kind of service very difficult. If I were to make another enclosure, I would design something that allows access from all sides.
All in all, however, I am very pleased with the results. For anyone who wants to improve their print quality, I would highly recommend building an enclosure!