3D Printer with Heated Chamber

I used a 3D scan of my head from the Maker Faire in San Mateo, CA collected at the Autodesk booth. The booth captures many simultaneous images from different directions. I used 123D Catch for processing. I later used this scan to make a 3D print of my head. Here is the scan shown on a YouTube video.

Here is the resulting 3D print using my improved 3D printer with a heated build chamber. I also used acetone vapor polishing on this print. The remaining delamination is unfortunately accentuated rather than covered by the vapor polishing. I think that brushing with acetone might have been a better choice for those problem spots.

IMG_0355

I have significantly improved the performance of my 3D printer by adding a heated build chamber. I built the frame of the chamber using 8020 extruded aluminum. The walls are some sort of particle board that I purchased at Home Depot. I added thin sheet metal, and (for now) aluminum foil behind heated elements in the chamber. There are only two holes in the chamber for the filament to come in and for the control and supply wires.

Here is the latest print (yellow) of my head compared to the result before adding the heated chamber (black). Delamination was a very serious problem.

IMG_0350    IMG_0174    IMG_0175

My ultimate goal of course is to have NO delamination. I intent to raise the build chamber temperature from 48-50 degrees C up to 70 degrees C. I have read that this is a better temperature for making very large, high quality prints.

By enclosing the build area, the bed, which is heated to 110 C and the extruder, which is heated to 230 C, and a light bulb (a CFA using 25 Watts) bring the ambient temperature inside the chamber up to about 45 C. Since I want positive control over the chamber temperature, I added a second heated build platform on a side wall. The job of this heating element is to control the air temperature. I use a PID controller (about 20 bucks on eBay) and a thermocouple suspended in the air to form a temperature control loop. There is a fan running constantly above the build area, drawing air away from the print and upward. This fan circulates the air in the chamber.

Before I can increase to 70 C, I need to first move the extruder stepper motor out of the chamber. I have seen other printers that push the filament far from the extruder. I might need a smaller diameter guide tube to make this work right. Another advantage to this method is that the temperature of the filament in the drive gear will be room temperature instead of heated chamber temperature. Since heated filament becomes soft, inside of the chamber it might slip on the drive gear.

Only three stepper motors will remain in side of the build chamber at this point. I have ordered water cooling blocks that I will attach to the motors. I have radiators and a fan that I will install outside of the build chamber. I will circulate and cool water to keep the stepper motors below the ambient chamber temperature. Two of the motors have fixed position on my printer (Y and Z), so only the X motor will need to be able to move with cooling tubing attached. This should be fairly easy to accomplish.

Here is a gallery showing the details of the improved 3D printer including the control circuitry mounted outside of the chamber.

I am really happy with the Kapton covered aluminum build plates. I use Windex to place a single wide strip of Kapton on each plate. Once it dries, I trim the edges. I then use a slurry of acetone and melted ABS to coat the top of the tape. The split platform makes it very easy to remove a finished print since I can just flex the plates to pop off the base of the print. Here are some images of the base. I have blogged about this technique previously.

I have my SLIC3R options set pretty well now. I used layer height of 0.2 mm for the first layer and 0.3 mm for all the rest of the layers. My support material is obviously working out very well. Here is a gallery showing the support.

Here is a short video showing the improved 3D printer in action.

I also tried splitting the object using netfabb and printing the halves separately. Here are images from that result.

Here are some pictures of the acetone vapor polishing process.

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4 responses to “3D Printer with Heated Chamber

  1. Pingback: Acrylic Sheet for Print Surface | G. P. Le Sage Blog·

  2. Pingback: 3D Printer with Heated Chamber | protomaker3dprinter·

  3. Nice work! How did the water cooling on the stepper motors turn out? Are they still working well? Have you ever tried printing polycarbonate inside the heated chamber?

    • The water cooled stepper motors work fine. In fact, one caused trouble with hoses in the way so I tried running it uncooled. At 60-70 C environment, it keeps working. I think most of those motors are rated for pretty high temperature. I have never tried polycarbonate. I have used ABS, PLA, and HIPS as well as conductor loaded filaments.

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