Sphere-O Robot

So, the Sphere-O-Bot was my first (and so far only) JJRobots project a few years ago (when I didn't have a blog). My 3D printer was not in the best shape but I was able to get everything assembled and working.

I dug out the Sphere-O-bot this week and after some trial and error I got it back up and running just in time for the Easter Holiday. One of the tricky parts was getting the software to work on an old windows 8 surface we had laying around. The software has three components:

  1. Arduino Leonardo Arduino drivers
  2. Inkscape Version 0.91 - Newer versions of Inkscape do not work.
  3. Eggbot Extention for Inkscape

Running the installers for the above is just the first step. I had a heck of a time getting the software to connect to the Arduino. It took a lot of googling and multiple problems on top of each other which made it tricky. One key thing I had to change was the following line in the eggbot_scanwin32.py file:

hKey = _winreg.OpenKey( hReg, r"SYSTEM\CurrentControlSet\Enum\USB\VID_2341&PID_0043" )

Turns out the VID and PID are unique to my system. You can figure these numbers out by using the Arduino software and looking at the board specifications or you can look them up in the device manager. Kind of tricky.

Anyway, once we got it working it turns out to be extremely fun. I purchased a bunch of ping-pong balls online:

STIGA 2-Star White No Print Table Tennis Balls (144-Count) by Amazon.com

These are reasonably priced and work well for printing. We have already gone though and printed a bunch of designs we download from the internet.

Example Printed Spheres

I also had my daughter draw a picture and put it on an egg:

Plot from a Drawing

There are many steps to getting this to work but they are all fairly easy:

  1. Draw a picture with only one color (to start) on white paper.
  2. Open up the eggbot svg Inkscape template file from the examples directory.
  3. Take a picture with my phone and email it to me.
  4. Upload the picture into Inkscape.
  5. Run the trace bitmap function in the menu. This will take some fiddling to get only the parts of the image you want.
  6. Edit the resulting vectors as needed.
  7. Highlight the entire bitmap such that all of the points are selected.
  8. Run the object to path function in the menu.
  9. Run the Eggbot Extension and print as normal.

The above instructions are really just notes for myself the next time I want to do this activity with the kids. If anyone besides me is reading this blog, please feel free to put a comment below or drop me an email and I am happy to put together more detailed instructions for installation and/or printing a picture.

Alexa Dot Holder

Sun 16 September 2018 by Dr. Dirk Colbry

Alexa Dot Wall Mount

My brother got me an Alexa Dot for Christmas a few years ago. It turns out to be a lot of fun. We put it in the kitchen and the kids play music. My wife and I also use it to add things to our shopping list (very convenient!) Anyway …

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3D printed Switch Guard

Wed 15 August 2018 by Dr. Dirk Colbry

Picture of the switch

We recently moved into a new house and the kids are having fun running around turning on and off all the lights. Unfortunately, some of the light switches are not for lights. One goes to our garbage disposal, another goes to the gas fireplace and another turns off the furnace …

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Sun 27 May 2018 by Dr. Dirk Colbry

FarmBot Logo

I have been coveting a FarmBot. At $2500 to $4000 these farming robots are a little out of my price range. However, I guess if I had a big enough yard I would still be looking to purchase one of these. They are so cool, they will plant, water, weed …

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Sat 19 May 2018 by Dr. Dirk Colbry

JJRobotics Logo

A great purchase for anyone with a 3D printer and looking for projects With the kids.

About a year ago I stubbled across JJRobots and I just love the idea of this company. They sell a kit of electronic parts to maker hobbyists with access to 3D printers. The idea …

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CNC Mill Picking

Fri 18 May 2018 by Dr. Dirk Colbry

I am interested in purchasing a CNC machine for the shop space in our new house. I think I would like to stick to something around $1000 but would be willing to invest as much as $2000 if I can find the right machine. There are a lot of choices …

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Intrducing a 3D printer to my daughter's Kindergarten class

Sat 09 May 2015 by Dr. Dirk Colbry


We had fun showing off my 3D printer to the Kindergarten class. Although the printer is fun to watch, kids tend to get board with it in just a few minutes. I like to come up with classroom projects that let the kids use things that are printed with the …

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Electric box extender

Sat 02 May 2015 by Dr. Dirk Colbry


I have been having trouble with my 3D printer over the last couple of months. It turns out that the fans got disconnected. Once I fixed the problem my printer is working better than ever. I was itching for something to print so I came up with this simple spacer …

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Ultimaker 2, cleaning a clogged nozzle

Sat 02 May 2015 by Dr. Dirk Colbry


So my Ultimaker2 extruding head got clogged, really bad. Something got jammed while printing and I could not get the filament to feed. This had happened once in the past when I tried using some really cheap filament but I am not sure the real root of the problem this …

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April 1st Brownies

Fri 03 April 2015 by Dr. Dirk Colbry

An oldie but a goodie with a modern twist. This year I printed out the letter E on my 3D printer using Brown PLA plastic.

Then I put the Brown E's in a baking pan:

Cover with aluminum foil and tell the kids I made brownies for them.


The were …

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