The guys at Moving Brands challenged us to help them print their own Chocolate Advent Calendar in a month.
We already knew about the Frostruder, and had most of the parts to build a RepRap Prusa, so the solution seemed obvious. They ordered a Frostruder, and we got busy building their Prusa.
Things got exciting when we tried to mount the Frostruder to the Prusa carriage - it was just too big and bulky!
Luckily, inspiration struck. We stripped down the Frostruder to the bare bones, and used the Prusa to print its own adaptor.
Lo and behold, chocolate printing goodness!
Moving Brands Advent Promotional Video: http://vimeo.com/33775105
Moving Brands Advent Calendar: http://www.movingbrands.com/advent
Print the syringe adaptor. The attached STL is compatible with the Greg Frost LM8UU X carriage (http://www.thingiverse.com/thing:9869). Edit the SCAD file parameters for other carriages.
Assemble the Frostruder according to the following steps in the instructions http://wiki.makerbot.com/frostruder-mk2-assembly (ignore the others):
a. Prep Work - Port Orientation
b. Prep Work - Connector Installation
c. Prep Work (optional) - paint/seal wood
d. Attach Valves to Syringe Bottom
e. Cut Tubes to Length
f. Attach Tubes to Tee
g. Attach Tubes to Solenoids
h. Cut More Tubing
i. Insert Tube into Stopper
j. Apply Clamps
k. Attach Syringe Tube to Tee
l. Attach Tubes to Input/Output
Mount the syringe on the X carriage using the adaptor and some M4 bolts (M4x16 or longer should do it) and nuts. Squeeze the two halves of the clamp together when tightening to get a firm grip on the syringe.
Mount the Syringe Bottom plate on the M8 threaded rod at the top of the frame use M8 nuts.
- Hook up the solenoid valves to your electronics, and adjust your firmware to power on and off the valves in response to the appropriate GCode commands:
M106 - pressure valve on (commonly Fan on)
M107 - pressure valve off (commonly Fan off)
M126 - relief valve on
M127 - relief valve off
If your electronics and firmware are set up to use a fan, it is usually sufficient to hook the pressure solenoid up in place of the fan. The relief valve takes a little more work, as it often requires appropriating either the extruder heater or heated bed connections.
Attach your compressed air source.
- Get printing! http://wiki.makerbot.com/frostruder-mk2-usage
For chocolate, you may wish to attach a syringe heated to keep the chocolate melted whilst printing.