Phoenix RepRap

Project Synopsis

We've been trying to brainstorm a good project idea that we can focus on to present to ASU for the $2000 grant we're aiming for. One project that would definitely put us on the map and would also allow us to reach out to the local community would be procuring a Rapid-Prototyping device. The RepRap project is a prime example of one whose initial creator's intention was not only to make a device that was as inexpensive as possible but also one that can replicate itself. Seeing the cost benefits analysis, as well as, the vast improvements with version II of this device(Mendel) we're thinking about going with that design.

--Update - ASU did not fund us so we did it ourselves. Take that establishment.

Design Summary

Check out the RepRap main site here:
http://reprap.org/bin/view/Main/WebHome

They've got a great video/mini documentary explaining the background of the RepRap concept including an interview with the designer:
http://vimeo.com/5202148

Check out the below link for a good video summary of what the "Mendel" is:
http://objects.reprap.org/wiki/Mendel_Overview

Construction

The RepRap team has done a pretty good job of ensuring that the design specs are open source so that the world wide community can participate in building and even bettering what they've started.

Below is their how to section on building a "Mendel" version of the RepRap:
http://objects.reprap.org/wiki/How_to_make_RepRap_Version_II_%22Mendel%22

Budget

This is a tally of costs so far, and providers used. You can see the original estimate on the rep rap site of $520 was rather low. With all the various shipping charges (plus we got 15lbs of plastic) we will likely almost double this. They also do not mention the impossibility of finding the prototyped/printed parts for the rep rap. They are approximately 100 hours to print and thus we've found few rep rap/makerbot owners willing or able to print those parts for us. These parts can also be rapid prototyped for around $1500 dollars which is slightly more than the advertised $20 dollars.

Located Parts

Item	US cost	Notes
Bearings	$76.14 shipped	TheBigBearingStore.com
Fasteners	109.20	Mcmaster.com
Belt	see Fasteners	Mcmaster.com
Extruder parts(machined)	$32.40 shipped	reifsnyderb on rep rap forums
Motors	302.85 shipped	Store.Makerbot.com
Plastic Stock	See motors	Store.Makerbot.com
PCBs	See Motors	Makerbot
Electronics	169.16	Parted out from Digikey, Allied,Arrow,Newark and Mouser
Thick sheet MDF, between 4mm and 6mm and at least 42cmx40cm	57.15	Lowes
Bar (smooth rod) BZP NOT BMS A2 Steel even better - at least 3m - M8 (8mm diameter)	See Thick Sheet	Lowes
Studding (threaded rod) -BZP M8 (8mm diameter) at least 9 meters	See Thick Sheet	Lowes
epoxy,ties	See Thick Sheet	Lowes
silicon grease, kapton tape	~33.00	Grainger
pcb strip board, heatshrink tubing,	n/a	Scrap
12 PC or laptop Power Supply	n/a	Multiple units donated by various members
5v FTDI	19.04	Sparkfun
Extruder parts - 6-ohm length of fibreglass-insulated nichrome wire,		http://store.makerbot.com/nichrome-wire-31-ga.html
Total	$>794.26	'

NEEDED PARTS

These are the parts we still need. Perhaps you can help?

Item	US cost	Notes
Thin sheet less than 2mm thick and at least 8cmx5cm	?	Beer can?
Printed Parts	?	Laser Cut, Rapid Prototyped, or Printed?
Misc - oil, box cutter blades, more?	?	Lowes, Home Depot
Total	?	'
Snap on EC or TC or newark.com sku:27K9987	?	25

Build Plan

Sorting parts into 'kits' (whole lotta parts to sort) Soldering - 2 or 3 stations probably (12 boards of various complexity) Testing Extruder building - going to be dependent on us getting prototyped parts in time Mechanical construction - going to be dependent on us getting prototyped parts in time

Status

Electrical

• Opto endstops tested and functional
• Mobo passing e testing--however z axis stepper function seems.. odd?
• 2 Stepper Controllers functioning
• 1 Stepper Motor - IC needs heat gun desoldering and re-seating
• 1 extruder motherboard processor needs heat gun desoldering and re-seating
• 1 extruder motherboard status unknown-needs testing

Mechanical

• >70% prototyped parts constructed
• Extruder construction begun-Have everything to finish
• X axis mechanical construction begun
• Y Should be ready to construct by next meeting
• Z Plastic in production currently--maybe ready for next meeting...

Insufficiencies in Rep Rap Documentation

Instruction issues

• Extruder page lists 5leds, but you actualyl need 9. (were 9 in partlist it would seem) Led1 and Led9 are actually named Power and Debug also.
• Need better documentation on Mendel modifications to build process. We accidentally did a lot of soldering we had to desolder.
• All mechanical construction steps don't actually give you any instructions, simply parts lists and completed pictures

Problems in Schematics

• Motherboard schematic claims 100u for c6, should be 10u as in documentation wiki

Missing from partslist

• 4 conductor ribbon for the extruder
• Thermistor for extruder
• 2 color 2 conductor 8amp guaged wire for power
• XLR connectors --which we're not using so thats fine
• We were short a length of 10 conductor ribbon
• Extruder lists 180ohm 1206 resistor as not required... I think? Or is it?
• Partslist doesn't list any of the mendel mobo modification parts --3v Voltage Regulator 78L33 or electrolytic cap - we don't need anyway as we went with a sparkfun 5v ftdi breakout which matches a breakout on the mobo and gives us our 3.3v and 5v both I believe

Unnecessary on partslist

• 30 watt resistor - 30w-5-nd (digikey)
• SPDT Slide Switch - as atx header isnt used on mobo anymore, switch doesn't actually switch anything does it?
• atx headers
• rj45