Reprap to the rescue: Fixed my daughter's favourite toy

Original Broken & Newly 3d printed lever

My oldest daughter's favorite toy is the Fisher Price Sink Set (1982). It's a toy that my wife used to play with when she was a toddler so it's quite old (no darling you're not old!) but still in good shape. Recently my daughter was upset because water stopped coming out when she pushed the lever. I opened up the set and noticed a broken lever that pushes a rubber pump.

 So let's fire up Sketchup and get the calipers ready and start drawing! Then generated an STL file (you need a plugin to generate STL files in Sketchup) and sent it to the Prusa I3 reprap.

I know one little person who will be very happy when she wakes up in the morning...

Let me know if you need the STL files. I printed in ABS with layer height @ 200µm and Slic3r Honeycomb infill @ 80% with a tiny bit of Brim (2mm)

A more complex calibration object...

Object STL: 5mm Calibration Cube Steps by MCroucher on Thingiverse
Material: 3mm ABS (Velleman from reprapuniverse.com)
Hotend: 245°C 1st layer, then 240°C
Heatbed: 115°C 1st layer, then 110°C
Heatbed adhesion: 3 layers of Fructis Bamboo Extract Hairspray, extra hold nr 6
Layer height: 0,2mm
Nozzle: 0,4mm
Gcode generated with Slic3r
Object printed with Pronterface

Issues

• the 10mm bridge is not that clean, the 5mm bridge is perfect though
• object is warping after some layers, need to find out why (more adhesion needed?, heatbed temp too high?, etc?)
• corners for short edges are more rounded off than corners for long edges (top 5 mm)

Good stuff

• Extrusion calibration is near perfect
• X, Y & Z-axis calibration is near perfect (calipers confirm!)

Maybe try PLA next?

Wiring done + Stepsticks driver current set + Extruder tested + Fried the Sanguinololu?

Wiring done for all three axis and the extruder stepper motors. Also the connections to both thermistors and the extruder heater and heatbed are ok. Still need to connect the fans to the ATX power source. (I connected the extruder fan to a free header on the Sanguinololu but I read this is a bad idea)

Setting the Vref to match my stepper-motor-driver configuration. My calculations don't match my measurements (calculated 2.24Volts and measured max 0.74Volts so my sense resistor value must be way off). But hey, the motors are working fine after some manual tweaking while listening to the motors' sound. I'll check what went wrong with the calculations later to fine tune the driver current...

This video shows the X & Z axis move during a test with Pronterface (the Z-axis moves really slow, this is normal).

Another milestone in the building process: To test the extruder I heated up the hotend gradually to 290°C and meanwhile extruded some blue PLA using Pronterface.

Open issues that need to be looked at:

Z-axis & Extruder inversion

The Z axis goes UP while going to the home position in Pronterface. Also the exdruder retracts while it's supposed to extrude and vice versa. So I need to reverse my stepper wiring from ABCD to DCBA or change the inversion setting in Configuration.h in the Marlin firmware and upload it to the Sanguinololu again.

Whoooops, I think I might have fried the Sanguinololu board :/

While fine tuning the driver current for the Y-axis i made a short circuit with my multimeter. Now my Y-axis won't move properly. Just when everything was going so good. Stupid me! 

Testing the electronics: moving the Y-axis stepper motor

Finally, something is actually 'moving'!

To test the Sanguinololu and the Pololu steppers and the connection to Pronterface I wired up the Y-axis stepper motor. Also had to connected both thermistors (heatbed & hotend), otherwise Pronterface returns errors about low extruder temperatures.

Warning!

The images in this video were extremely exiting for me,

but will be disappointing for any other 'normal' person..

Sanguinololu ATX Powered & USB connected to Pronterface

The Sanguinololu board is powered by a 400 Watt ATX power supply.

You really need to short circuit ATX pin 16(green) to ground(black) to enable power(!PWR_ENABLE) on the 4 pin connector.

The USB Connection goes to to a Virtual Serial COM port on the PC.

Started up Pronterface and successfully connected to the "printer" (still need to do all the wiring) using COM port 3 with a 250000 baudrate

The smoke test didn't cause actual smoke so i'm happy!