Binary Construct

The McWire bot is up and running again-this time with g-code support! As a test, I sketched out a NEMA 17 motor mount and wrote the gcode to cut it out from a sheet of acrylic. It was actually easier than I though it would be. There are really only a couple codes needed to drive a McWire with a dremel tool attached as a milling head.

The following are the primary codes used:

• G0  - Move to Cartesian coordiantes fast

• G1 - Move to Cartesian coords. precise

• G3/G4 - Draw an arc(CW and CCW)

Here are the bookcases I have been building to make more efficient use of the space in the lab. With a little stain and few coats of polyurethane they will be ready for use, and I can get back to working on the RepRap.

If you want to use the Sanguino on the motherboard for anything other than the RepRap firmware, you can do one of the following.

The first photo is the nozzle and heater barrel for the mk 2 extruder. This photo was taken immediately after wrapping the nichrome wire around the barrel and covering the whole thing in high-temp furnace cement. The furnace cement will act as glue, keeping the heater element and the thermistor in place as well as an insulator, allowing the heater to get hotter than it could otherwise. 

You can see the leads for the thermistor poking out the lower part, and the heater element on the upper side. 

In the second photo you can see the old heater/nozzle and wooden extruder. This design had far too much friction and the motor couldn't put enough force on the plastic to keep the extruder flowing. The original design also used JB weld instead of furnace cement.

Last night I tested the stepper driver and the motherboard and it works! (Turn your sound on)

I am in dire need of upgrading my workspace with some shelving. I may put the development on hold today until I can get this place straightened up. If you look in the far corner that silver-gray thing is my video editing computer. Someday when I get everything cleaned, and I can reach it, I will work on the ski trip video.

The Generation 3 electronics are a major leap forward in technology, going from thru-hole components to much smaller SMT components.

To solder these, you first squirt a small dab of solder paste, carefully place the components on with tweezers, then heat the whole thing up on a hot-plate. It is actually easier than it sounds, once you start heating up the board, all the tiny parts suck into place and it is really fast.

The board to the left has a build in Arduino controller, and is used to drive the extruder motor, heater and read temperature. It can also drive servos and serve as a time-waster at work while explaing it to co-workers.

However, I did have a few problems with the main control board...

So far my attempts to make a new extruder that works for more than a day have not been successful. My goal is to build an extruder with parts I already have and without any printed parts. This extruder is based on the 2.0 extruder as well (although I'm using the old solarbotics motor).

The back plate would be made of some sturdy material (lexan / aluminum / steel) that I have in abundance. Gears would be salvaged...most likely from busted drills. The tubes would probably be steel tubes. The gold thing is an extra skate bearing I have from building my RepStrap. I have two or three nozzle/heater barrels working so that part is already complete.

The main problem I have with my design is attaching the heater to the rest of it. Another concern was the speed of the motor, the gear ratio could be adjusted; this is just a proof of concept to better visualize the design.

More after the break.