banner perso

Some links about me. Many of my 3D designs are free. I also post on Google+ and in another blog, oz4.us
review (32) general (26) issue (16) mechanical (16) replacement (14) software (13) addon (12) bowden tube (10) business (10) consumables (10) heat (10) feeder (8) hot end (8) weird (7) motor (6) off-topic (6) trick (6) electric (4) bed (3) cnc (2)

Friday, June 27, 2014

Four in the morning. Just had a few tweaks to finish my upgrade...

Eventually "implemented" my upgrade! I certainly did not think it would take me so long, but once you start to sort the mess that's below a 3D printer you just can spend days on it! There is a brief list after the break.

I am sure a lot of 3D printer owners share the "two minutes into two hours" syndrome.

What I did...

  • Sorted some cables: cleaned up the mess, shortened some, refreshed the aging connectors before they start to fail. Fully replaced the main cable from the bottom to the head, by means of a high quality Ethernet cable (I feel confident). Used lots of JST 2 and 3 pin, with a high quality crimping/terminal pliers (ref. "Engineer PA20" worth its $75, ouch -- also have a very good wire stripper from the same Japanese brand). I failed to select the proper crimps at first (I was "close" but it is clearly not enough to be close!). I should have payed more attention.
  • At last I now have a proper dual power supply (5V and 12V, based two high efficiency, low temp and cheap LM2596). Will power whatever I need without having to deal with 19V or to load further the existing inefficient linear regulator on the RAMPS.
  • Re-did my secondary Arduino Pro Mini. This time it is clean! I used some proto board.
  • Added a secondary OLED display (128x64 pixels, $8 on ebay) with its own rotary encoder and probably too short a cable (I recycled both the cable and its connectors...)
The secondary Arduino, screen and encoder will give me a lot of freedom for further enhancements. Too bad I have only one wire left from the Ethernet cable to the head, but at least I now have proper 12V and ground, with one more free wire (eg. I could multiplex control signals with I2C and an ATtiny when I need it).

For now I can tune the bed temperature (was either 0 or 55°C before), PWM for the hot end heatsink fan (was very noisy at 100%), and PWM for the LED lighting (quite useless but I can switch them off at least now). I know, I should switch the bed control to the main board & firmware. At least I do not interfere further with Marlin even though it is trivial to disable the bed PWM. Going "bang-bang" with a 2°C hysteresis on a mechanical relay really is enough for me. I can even hear when it is heating (but now I have it displayed on the pretty little oled screen).

What I should do...

  • Shorten all these long stepper cables. Why are they so long in the first place?!
  • Print support and boxes for the 3 boards (dual power supply, secondary arduino, mini screen and encoder)
  • Print cable ducts
  • Ditch my flexible led strips and use led bars instead
  • Add a watchdog on the printer to shut it down when nothing happens (eg. vibration/noise sensor), or when heat or electric power reach unusual values (as a security)
I could keep on listing tens of ideas here... stay tuned!

No comments:

Post a Comment