Printing a Rostock MAX build plate filled with ABS is a challenge. The biggest problem is "warping," especially when the design has corners that lie near the periphery of the build plate. Last night I started a print that ran for just over 12 hours. It was my first truly successful print that used the "whole" build plate. Below are a few photos and some detail of how I got this to work.
The following .pdf is a 3D version of the CAD file I printed. This is the faceplate for my "Motorcycle Information Display." When you click on the link the.pdf will open. After the file opens, click on the image (when you see the message "click to activate"). When the image changes colors, right-click on the image and then choose "Full Screen Multimedia" from the menu. You can then drag the image to rotate it 360 degrees. You can right-click on the image and get a number of other viewing options. Press the "Esc" key on your computer to exit Full Screen Multimedia. This is a complicated CAD file. As you saw, it includes mounting surfaces and screw bosses on the underside of the faceplate. And the faceplate is big!
Here are photos of the print I did on my Rostock MAX:
The KISSlicer produced one big error in its G-code. This caused the file to "lock-up" as it printed a "mouse ear" at the ENE corner of the model. Apparently the microcontroller's "watch-dog timer" was able to resume the print after about 60 seconds. I have had the KISSlicer develop other sets of problem code when it attempts to develop G-code that prints near this same position. I'm not sure what it is doing (and I assume it is the KISSlicer G-code) but it frightens the bejeebers out of me when it happens.
To get this print to work I had to carefully align the aluminum extrusions on my Rostock MAX to ensure they were perpendicular and "plumb" to the build surface. This is discussed in the following thread: http://forum.seemecnc.com/viewtopic.php?f=54&t=1571.
I also had to fight the "doming" that occurs when my Onyx bed heats to temperature. To make a long story short, the paper shims you see in my photos (the light green pieces of paper) appear to have done the trick. These shims are .1mm thick. I slid them just under the Onyx heated bed and then ran the flat head screws through them. I screwed the screws back in until they just touched the Onyx heater plate. I did not want them tight - I wanted the bed to be able to move if it needed to as it heated. I felt the combination of this "freedom to move" and the shims minimized the tendency for the Onyx to dome as it heated.
I carefully set my Z zero on the surface of the build plate (a piece of 3.175mm thick glass). To do this I followed the "traditional zeroing routine," but I used "wider" coordinates to set zero at the base of each axis. The coordinates I used were, X-Axis: X-86.603, Y-50; Y-Axis: X86.603, Y-50; and Z-Axis: X0, Y100.
I worked to calibrate DELTA_RADIUS in the Configuration.h file of Repetier, too. I ended up using a correction weight of "-.2".
When you look at the photos of my print very closely you'll see I have a little more adjustment to make in my printer settings. But, I think this print will allow me to "test fit" the LCDs I'm using. I'll print the rest of the enclosure (2 more pieces) and then I'll get my Motorcycle Information Display on the road.
I'm pleased with my Rostock MAX and what it is allowing me to do!
Bill
