Sphere-O-Bot Remix

thingiverse

This is a remix of the JJ Robots version of the Sphere-O-Bot, when I assembled mine I found there was a great deal of slop in the axis and the drawing arm that would have a negative impact on the outcome of my prints. I redesigned the axis support to hold the bearings snugly. The bearings floated in the original which allowed play in the axis, I found it difficult to align the egg with the slop in the axis. If you use mine it's helpful to put the bearings in the freezer for an hour or two, this allows the bearings to shrink a little bit during assembly, even still it's a snug fit. To correct the arm I designed an arm specifically to hold a Sharpie Ultra Fine Point marker. This is only intended for the Sharpie and holds the pen at the right height and snugly enough so there is no lateral movement. It allow precise alignment when changing pens for a color change. For another project I added an arm for a Jot Marker, both are included. The Jot marker arm has the shorter sleeve. The vertical arm as designed made it difficult to remove the slop in the axis where the pen holder meets the vertical arm. It requires you to adjust the screws so that they're snug enough to keep the arm from sliding side to side without interfering with arm lift and drop. During long prints I found the arm would start to bind when lifting and dropping, sometimes it wouldn't allow the pen to come in contact with the egg, I think this may have been due to movement warming up the contact between the screws and the vertical arm causing binding. To eliminate this I redesigned the vertical arm to hold two bearing of the same type used in the axis, you still need to adjust the screws so they'll allow pen lift and drop while removing any side to side movement, however, with the steel bearings I find this easier to accomplish and allows freer movement of the pen holding arm. Again, freeze the bearings before install, it's a snug fit. Lastly the vertical arm on the original was held on with just friction, I redesigned it for a nut pocket and a hole for a 3mm screw. The Main Frame is for the JJRobots DEVIA board. The EiBFrame is for the Evil Mad Scientist EiB Board. I designed and added a bearing press to make it easier to install the bearings, print with 100% infill and use an M3x25 or M3x30 screw to pull everything together. I've left all the original parts in the kit, you'll need to select which ones you wish to use.