Printrbot Tip: Leveling the Printrbed
Shortly after assembling and caibrating my Printrbot, I was able to print out my first object (Mr. Jaws by Mahoney in case you were wondering), but it took me a few tries to get the first layer to lay down right. I was able to get it working by increasing the bed temperature for the first layer to 130C from the default of 110C. I am unable to see what the actual temperature of my bed is, because the only thermocouple that I have was not working, but it should be close. Even with the higher temperature, I still had some troubles with parts laying down. Although I did try and level the bed the best I could, I rechecked it and it definitely needed some more work. After messing around with it for a while longer, I figured out the best way to get everything as level as possible.
As Brook suggested, the bed needs to be leveled with washers on the four corners. After some time, I figured out that the best way to do this is to put the same size washer under each corner so you have the ability to move each corner up or down as needed. I used a pair of Digital Calipers to measure the thickness of the washers I had. The majority of them seemed to be 1.5mm so I used that as the base on each corner, but I also had washers with thicknesses of 1.3mm, 1.4mm, 1.6mm, 1.7mm, among others so I could swap the washers out to get small adjustments in the Z-direction in each corner. I once again checked the area of the Printrbed with a slice of paper in between the bed and the extruder tip, and although it was not perfect, the next object that I printed came out without a hitch. That object, by the way, was Pi Keychain / Backpack Charm by CodeCreations.