Category Archives: 3D Printing

Sharp PC-G850 Serial over WiFi Module

YAEP (Yet Another ESP Powered Project): An ESP8266-12 powered WiFi module for the Sharp Pocket Computer via the 11-pin connector connects wireless to PCs for transfer of programs and data. The ESP8266 connects to your home WiFi or acts as an AP for initial configuration. The Serial port of the G850 becomes accessible via TCP on port 23. You can use telnet or netcat (nc) for simple direct transfers to/from the PC or use socat to create a virtual com port. The module supports 9600baud and shortens CTS/RTS and pulls these signals up to +5V, so you need to use XON for flow control. Please note: The G850 uses inverted serial protocol logic levels (i.e. logical “high” is represented by a “low” (0V) TTL level, logical “low” is represented by a 5V TTL level. The ESP8266 uses the SoftSerial library on GPIO 4 and 5, which supports inverted logic levelsRaw TCP is implemented without encryption on port 23. You can connect via telnet to receive or send data or programs but everyone on the same network can read the transferred data in clear textThe module does only support asynchronus serial communication (i.e. it does not emulate the CE-126 synchronous communication for print and cassette tape commands)In the TEXT/Sio/Format menu enable 9600 baud, 8N1 and no flow-control. End-of-file “1A” allows the G850 to stop listening when receiving a file. You can still send files without the end-marker, but need to interrupt the “load” command by pressing “ON/BREAK”. The received text will be in the editor. No…

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Micron 3DP Metal Extruder

Adding an all-metal extruder to a Prusa i3. The Wade extruder on my i3 started to slip and not enough filament was extruded, so the prints started to look flakier and flakier. I checked the extruder, refurbished the hobbled bolt, but the problem came quickly back. Only once I increased temperature to over 230C (for PLA!) it completed prints – of course the result looked like roasted marshmallows. So I ordered a new J-Head hot end (0.4mm) and a new all-metal extruder. Price on ebay was $175 plus $20 shipping. Quite steep, but I have no regrets! Build quality is excellent and the Nema 11 stepper has plenty of power thanks to the gearbox (at first, I used same driver setting as for my Wade extruder’s Nema 17 and subsequently the stepper would become very hot. Adjusting the reference voltage of the driver board to 0.45V solved the problem). I had to print a new mount to fit the extruder. That was a bit of a challenge, given I own only one 3D printer, and that one was broken. I managed to get one decent print: enough to mount hold the new extruder in place. Once I had the printer re-adjusted (M92 X80.00 Y80.00 Z4000.00 E1333.33), the first task was to print a better mount. Result is attached below.   Not sure if it’s the new extruder or the recalibration of the machine (incl. resetting x and z end stops), but now I am finally able to print straight onto glass (using a watered down…

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