Project:25-hpamakers-reprap
Aim
Finish construction of the printer ASAP and get it running reliably!
How?
Current Development Milestones
1-Construction
PLA Parts Needed (as of 17:18 On Wed 11th May 2011)
3 x Endstop Holder
2 x Pulley
6 x PLA Bushings
Parent folder for the Prusa STL Files
2-Firmware
(Sam)RepRap Motherboard v1.2 firmware installation.
Notes:
3-Testing
(Sam) Check Wiring + Firmware: Desktop-based test of all stepper motors and electronics.
Notes: I am going to be flashing the firmware using an FTDI cable and then I will check our USB to serial cable.
(Kal) Check Mechanical Construction against instructions + Begin Calibrating
Notes: Hey Kal, Sam here, in order to mechanically calibrate the frame I would recommend going through part 5 (page 32) of this visual guide: http://garyhodgson.com/reprap/prusa-mendel-visual-instructions/ We might need to cut some more steel stock if any of the lengths are too short.
4-Commissioning
Begin printing Make first model Make first part Make first set of parts
Who?
What?
3D Printer
Sam: I am constructing the printer using this really great guide: Prusa Visual Instructions
Mendel Specifications
The table below outlines the specifications of the machine.
| Metric | |
|---|---|
| Model | Reprap II: Mendel "Mendel" |
| Technology | FFF (Fused Filament Fabrication)/Thermoplastic extrusion |
| Price of all materials | €350 |
| Annual Service Cost | Occasional oiling = €5. It can print its own replacement printed parts at material cost. |
| Size | 500 mm (W) x 400 mm (D) x 360 mm (H) |
| Weight | 7.0 kg. |
| Build Envelope | 200 mm (W) x 200 mm (D) x 140 mm (H). |
| Materials | PLA, HDPE, ABS & more. Uses ø 3 mm filament. |
| Material Cost | PLA: €22/kg, HDPE: €11/kg, ABS: €17/kg. |
| Speed | 15.0 cm3 per hour solid (test done for PLA, similar for others). |
| Accuracy | Diameter of nozzle 0.5 mm, 2 mm min. feature size, 0.1 mm positioning accuracy, layer thickness 0.3 mm |
| Finish | Fair |
| Volume of printed parts to replicate | 1110 cm3 |
(With the standard infill settings the 15.0 cm3 per hour solid extrusion rate is equivalent to a built volume rate of 19.0 cm3 per hour.)
Consumables
Blue Decorator's Tape
PLA, HDPE, ABS Filament
Computing
Netbook with Solidworks and Reprap Host Software.
Power
Converted 300W ATX Power Supply. +12V and GND. 5A current.
Electronics
We are using Generation 3 Reprap Electronics
USB to TTL Adapter
Based on the FTDI FT232R.
Fig. 1
Currently the connector is wired such:
GND DCD# VCC TXD RXD RTS#
While the Sanguino (at least v1.0) expects:
GND GND [USB_5V (VCC)] RXD TXD RTS#
Fig. 2
From the datasheet:
Fig. 3
It can be inferred that the correct terminals on the cable in Fig. 1 should be:
GND GND VCC TXD RXD CTS#
All said, the extruder and main motherboard (gen 3 reprap electronics) have been successfully flashed using this controller so perhaps the critical lines are in, one GND, VCC and TXD plus RXD which afaik handle the data transmission.
Motherboard
Reprap Motherboard v1.2
Stepper Motors + Driver Circuits
3 x Stepper Motor Driver v2.3 r1 boards 5 x Nema 17 Stepper Motors
Where?
Why?
Google Docs
Where?
London Hackspace: http://london.hackspace.org.uk/
Why?
Because we want a 3D printer!
