2017. április 20., csütörtök

MVP Reconnect gift arrived

Finally my MVP reconnect gift arrived from Microsoft:

GeeeTech 3D Printer 7.

Yeah, facepalm.
This guy still struggling with that crap.
Many of my designs are come out from the printer seamlessly until I get into my mind to build a Cyclon PCB Factory (actually I seen in somebody's facebook post and checked, what it is).
It has several printed parts. When I started to print, at the second batch I got this:

Yes, you right it is the vengeance of the Cyclon PCB Factory because of the PINK!!!
So, I started to look around and read. I found two factors:
1. You should lower the temperature for PLA as it melts to long into the heatbreak and stuck in it if not flowing fast enough.
2. You should use some Canola oil, to prevent sticking the plastic into the heatbreak.
1. I went down to 195°C, and ordered a better fan for the heatbreak radiator (not arrived yet)
2. What a hell is that Canola. I looked around. It is called "repce" in my country. So bought a liter of it (there are no smaller available):

And the result is here:

Ok. But one good print doesn't tell anything. I achieved this in around three days without a single problem:

I guess. It is working now. Finally.

2017. április 19., szerda

GeeeTech 3D Printer 6.

When the shit hits the fan. :-D
As I tried to work with it. I had a small accident. Something was hitting hard the extruder fan while it was running:

The sad thing in it, that it was a Sunon Vapo fan, what I prefer, and had no more of this at home.

2017. április 18., kedd

Ergobag 1.

This is an old story. It dated back to the end of last summer. My two kids, who already in school has identical school backpacks but in different color.
These backpacks has a few places where stickers can be attached with velcro. The kids got some stickers with the bags, but these are just static ones.
Here came the idea. What if I create something personalized for them. Something with their own name, what even has some light in it.
So I needed a 3D Printed cage, with some electronics inside. To keep it simple I chosen an Attiny85 and APA102 LEDs.
I wanted something can be charged. To keep it as slim as possible, the normal AA or AAA size rechargeables was not really a good option (first I was thinking about, but finally I thrown the idea). So I chosen a Nokia BL-4C battery. There are two problems with it. You need a proper Li-Ion charger and as the LEDs need 5V, you need a boost converter to power it.
In addition I wanted to cut of the power after certain amount of time - Kids never switch of the toys.
So one push button for switch on, one for switch off if you want, and timed switch of by the MCU.
Here is the circuit:

I built this on a circular board:
(This is the first prototype, not the actual working one)

Then I designed a case for it.

Actually I was able to print the 3D parts and assembled the whole thing, but I wasn't really happy with the result as I had continuous problems with the 3D printer (the Geeetech, as the Robo3D was completely dead)
Finally the signs appeared on the bags, and the kids were happy with it:

The project was closed...
...but, as you can expect kids, are kids, and they have schoolmates. So "orders" arrived - who else needs it. :-)
All of the design files are available on my github:
It has been cleaned up, so just the actual design is in there.

2017. április 10., hétfő

GeeeTech roll holder

The GeeeTech printer came with a separate roll holder. It is uncomfortable to use and take unnecessary space.

To overcome this, I wanted to have something better.
My wife just thrown away this as the holder at the end was broken:

I decided to cut it into the desired length and design a holder for it, what fits onto the top of the printer.
The printer hase 4 holes at each side, I don't know why - no it is not he holes for the bowden extruder, different holes what I talk about.
So I designed a plastic part as the holder (two identical required), and printed.
Here is the result:

It is available on Thingiverse: http://www.thingiverse.com/thing:2235889

2017. április 8., szombat

GeeeTech 3D Printer 5.

Oh no. It still not finished.
I had the feeling, that I finished the problems with my GeeeTech printer.
I started to print and my designs came out nicely. I was using some old PLA rolls from 3D Factory (I guess) and the roll of blue Geeetech PLA came with this printer.
I was working on a fun project to my kids. One of my daughters wanted her thing in pink (what a surprise). I had a roll of pink material from Herz filament.
The result was devastating:

The solid layers (let say the first 2mm) came out correctly, but the hotend stuck afterward.
Tried it many times, with the same result. The same design was working correctly with the GeeeTech blue.
Tried to change the temperature, not helped.
So I had the feeling that something is wrong with the Herz material. I ordered another pink roll, this time from 3DW.
Next try, same result. Oh shit, so there should be other problem.
I started to think. What is the difference between the solid layers and the small parts printed later?
The retract.
On the solid layers the extruder almost never retract the material, on the tiny parts above, continuously.
When I built this printer I chosen a E3D v6 hotend clone for it. It had teflon tubing in the heatbreak what I didn't like, so I replaced it with the heatbreak of my unused E3D v5.
There is something wrong with tihs?

As you see the hole size of the v5 barely bigger than the diameter of the filament. The v6 give much more space. When the filament retracted the liquid bubble on the tip of the filament cooling down and stuck into the heatbreak.
Cleaned, replaced, and here is the result:

Just I don't know what the hell will I do with almost 2kg ugly pink filament.

2017. március 28., kedd

GeeeTech 3D Printer 4.

I didn't want to give it up here, or wait for the bearings to arrive. At the thingiverse on one of the Geeetech pulley's description I seen something about, that they used bearings without pulleys in the past.
I checked, the bearings in my parts box has 4mm hole, and two of them nicely fits into the pulley holder. Yes I know, that keeping the timing belt in the center is almost impossible from now.

The printer started to work, now more clicking noise.
...or not?
Started to hear the awful clicking noise. This time it was coming from the Y axis (the bed). Replaced the pulley with bearings also here.
Started to print.
It looks like the X and Y axis looks working, but I started to loose the layer adhesion at a certain height.

I thought that the Z axis needs some lubricant (as it already sounded awful during fast moves). I was looking around but found nothing. Not even some WD40.
Next day I picked up this in the shop:

Now my prints are coming out as good as never before:

At least not from this printer.
I think the build/repair of the Geeetech printer is finished now. Regarding 3D printing I can concentrate to the improvements, repairing the Robo 3D and printing parts for my other designs (like my son's plotter)
The End

2017. március 25., szombat

Project 2017#1 - ESP8266 Programmer Github

As I promised here:
cleaned the GitHub repo of the ESP programmer. It also contains the ESP based development boards of mine.
The repo can be found here:
If you need the libraries/modules I used for this, it can be find under my KiCAD libraries/modules account here:

The surgery succeeded, the patient is dead

I got two fairly dead Electrodragon relay module from a friend to try to repair it.
The first looked like maybe repairable:

The second is completely dead:

From this wanted to salvage the terminal blocks from the secondary side to repair the first module, and the ESP module to put onto one of my dev boards.

Removed the blocks and the ESP from the board.
Created a new dev module from it:

The build succeeded perfectly (I'm getting better in SMD soldering),
but when I connected it to the programmer even the programmer felt out from the USB bus.
So the surgery succeeded, but the patient died.
I also repaired the first module, but as is it mains connected I don't want to try out without some precautions. I don't have more time for this right now.

2017. március 22., szerda

GeeeTech 3D Printer 3.

I had two problems:
My prints show that I've an X axis wobling issue. It is too much that can be caused by the Z threaded rods (anyway I handled that originally):

I was "monitoring" the printer with my ear during printing.
Realized that the clicking noise is coming from the Z bridge assembly's right side. My guess is there is something went terribly wrong with the timing belt pulley.
Disassembled it.
I was right.
This "was" one of the tiny bearings inside the pulley:

I tried to find a similar bearing.
Looked in the box containing the original parts of the GeeeTech printer - they provided spare parts for some things - not this one.
Looked in my box of bearings - no this size
Looked around on the net if I can find what is the exact type. I was only knowing the physical size 8x4x3 mm. After some iteration and guessing I know the type: MR84ZZ
Ordered from Aliexpress. It take a while, so I was looking for a local source. Find it, ordered it.
In the meantime I wanted to resolve the issue to be able to print.
On the thingiverse I found a replacement pulley, what has no bearings inside:
I tried to print it out with only one bearing in the original pulley. It failed.
After a good start. I've a broken 3D printer. Again...

2017. március 21., kedd

GeeeTech 3D Printer 2.

A few days ago a new project come. My son "ordered" a pen plotter (he said we will build it together).
This definitely needs some 3D printed parts. So I decided to repair the Geeetech printer.
  • I rebuilt the Raspberry PI, Ubuntu, Octoprint set using the newest versions.
  • Replaced the Bulldog motor with a higher torque one.
  • Replaced the TI driver for a new one. Just to be sure if it works correctly. Set the motor current to 1.2A (the max is 1.5A)
Finally It started to print. But...
I still hear the clicking noise from the extruder. It looks like it doesn't loose steps as the filament is coming out from the hotend as expected. I don't know what it is. I can't do anything about it right now.
So I've a working 3D printer. Or not?

It's starting...

As every year for a while, it is time for the yearly big Hackaday competition:

Here you can read more about it:

Actually I not really have any good idea for it, so I've to think what I want to build this year.

2017. március 20., hétfő

2017. március 19., vasárnap

GeeeTech 3D Printer 1.

Ouch, I started to write about my new Geeetech 3D printer more than a year ago. I didn't finish that post, so I'm extending it now.

I started the build in December 2015. Later on suddenly my Robo3D repaired (I done a few steps on it, it started to work as perfectly as never before: http://pakahuszar.blogspot.hu/2016/01/3d-printing-seams-working.html)

About the build:

  • I'm not really satisfied with the building instructions. There are many errors in it, like listing wrong screws, building timing belt assembly for the bed completely useless, requiring the videos for some parts, because the instructions are not enough, etc. But on the other hand, I seen much worse manual already
  • The supplied 180W power supply is a joke. Five steppers, the electronics, the 40W head heating, and the bed. It will hardly keep this going. According to Thomas Sanlederer's video, you need 0.6W/cm2 for the bed (200x200cm bed require 240W). So I replaced it to a 500W one.
  • Looked around the forums, I found out that the supplied MK8 extruder is a crap. Use teflon tubing and even the motor can't provide the required torq: http://www.rc-cam.com/forum/index.php?/topic/4034-geeetech-mk8-extruder-tips-tricks-3d-printers/. So I decided, to change this to a Bulldog Lite/E3D v6 combination (the project stopped here for a while - waiting for parts and spare time)
    • Created a holder from a 25/60mm aluminum L extrusion

    • Rearranged the Z endstop, as the new hotend is longer.

  • Cut a few centimeter shorter threaded rods to elliminate the X axis wobling:
    Cutting the rod was less destructive than the original solution (btw. I kept the original rod and bought a new one in the local hardware store)

  • Added a borosilicate glass to the top of the aluminum build platform and mounted it with the supplied paper clips
  • Added a Raspberry Pi 2B with Ubuntu + Octoprint to drive it.

The above was finished during the last summer. It started to print, but the extruder's stepper continuously losing steps, or even stuck.
I tried to replace the Allegro driver to TI one, but not really helped. After a few prints around September/October I gave up.
In addition the Robo3D also stopped to work with the usual extrusion problem. So I gave up the 3D Printing for a while.

2017. március 15., szerda

Project 2017#1 - ESP8266 Programmer 3.

I've seen on the ebay programmers for ESP-01 module. All of them use push button for flash/reset, what was unacceptable to me. So I designed something. Not a standalone programmer, but a small extension for my ESP8266 programmer. It nothing else just two connectors and the three pull up/down resistors:

Connected to the programmer:

In work, programming an ESP-01:

To make this work, here are the settings I used in the Arduino IDE:

May some settings need explanation:

  • I used Generic ESP8266 Module to see all of the possible options.
  • QIO mode is the fastest flash access method and as we use ESP-01 here using the GPIOs occupied by the QIO is out of question.
  • 4M flash size - I replaced the 512k flash chip with a 4M one (http://pakahuszar.blogspot.hu/2016/10/esp-01-surgery.html) so it is the correct one here
  • Reset Method - nodemcu - this is the most important setting here, as this makes possible to run the programmer automatically without pressing buttons.
I think, with this I can tell, this project is finished. The only thing left, to update the github repo of it.

2017. március 14., kedd

Project 2017#1 - ESP8266 Programmer 2.

The ordered board arrived from SeeedStudio.
I built it:

It works perfectly.
Just a quick note to myself: You have to solder the USB connector first otherwise you can't access the connector pins with the soldering iron.

2017. március 13., hétfő

2017. március 11., szombat

Project 2017#2 - ESP8266 Breakout Board

Yes, you can tell. Why on earth you creating yet another ESP8266 development board? There are plenty of them already available. Just check NodeMCU, Wemos D1, Sparkfun, Adafruit modules, just to name a few.
The main reason is that I'm an idiot.
I wanted to access the bottom pins of the ESP12E/F Modules:

And didn't realize that it is already available on the NodeMCU v1.0 on my desk.
So I designed and built one:

At least it is a breakout board with access to the bottom pins, without the USB/Serial adapter, what can fit in my future projects.

Now a few words about why I want these pins.
On many forums people written about these pins, that they are useless, as used by the flash chip of the module exclusively.
I'm a stubborn person. I don't believe what they said. I want to try this out myself.

Now let see, what I intend to achieve with this board. I'll mark these as tasks during the following write up.
The main problem, that the ESP8266 has a capable CPU, easily programmable Wi-Fi, lot of flash to store code and data, but limited GPIO capability. Yes, you can use bus extenders, but it isn't the same.
Let see what GPIO we have.
First of all the GPIOs can be freely use:
It is five, not to much if you know that SPI or I2C also can only be mapped to here.
There is also the GPIO16 maybe free, but some reports written, that it may disrupt the reset process, and it is involved in the deep sleep.
Lets continue, what else we have:
GPIO1, GPIO3 can be use if we give up the serial port used for programming and serial messages, what is quite useful during the development phase or later diagnostics.
As I want to keep this functionality I will not play with it now.
GPIO0, GPIO2, GPIO15 are used during the bootup process. This means the GPIO0 and GPIO2 pulled up and the GPIO15 is pulled down during normal boot (it isn't true when you program it or booting from SD Card).
If you don't care the state of these pins during boot process and aware of the pull ups/downs later on, you can use them as outputs, but doesn't recommended to use as inputs, because it can disrupt the boot process.
I've a simple external circuit in my mind to overcome this. So mark this as TASK#1
GPIO6-GPIO11 used by the onboard FLASH (the bottom pins).
Here is a small table, how they are connected:

GPIO7    SDO0      MISO
GPIO8    SDO1      MOSI

The connection to the FLASH is required all of the time, so these pins can not be used (freely).
The system allows two modes (maybe more, but we just talking about the most common ones used in the ESP8266): QIO and DIO.
In QIO mode all of the SDx pins are used. In DIO mode just the SD0/1. This means the GPIO9/10 remain free. Check if I can use them. So mark this as TASK#2
In some documents I found some information of the HSPI remapping to the SPI pins of the flash. In theory if I use the CS of the HSPI for some external SPI peripheral (4 wire SPI), I can share the SPI between the flash chip and this external peripheral. Mark this as TASK#3
According to the documentation the ESP8266 can boot from SD card instead of the internal flash. It would be interesting to figure out, how can this be achieved. So mark this as TASK#4
This is all for now. I'd like to research the four tasks mentioned above, and write about the successes/failures.

2017. február 25., szombat

Quick and Dirty - SMD LED Tester

I needed an SMD LED tester for my ongoing project. Unfortunately the local parts store puts everything into a single paper bag without designation, so I wasn't able to distinguish between the red and the blue 0603 LEDs.
A Kelvin clip from eBay, two banana plugs, a 330 ohm resistor, some loudspeaker wire, and lots of heatshrink.
The resistor in the wire:

The finished "instrument":

First I thought that the shorter heatshrink on the clip's leg will designate the positive lead but later realized that it would be a great idea to put heatshrink onto the tips and in this small size I had red one also.

2017. február 18., szombat

Project 2017#1 - ESP8266 Programmer 1.

It's been a while I didn't write anything. It doesn't meen I didn't do anything, just had no time/lust to write.
Here is my first project in this year (to by honest I started it in 2016 but it is the time to finish).
I started to work with ESP8266, and as many of us I bought the NodeMCU 0.9 board (years ago to be honest). This is a great board, to begin with it, but I don't like to put such ready made boards with programmer, regulator integrated to put into my projects. I prefer to have my own regulator, bare chip/module, and some ISP interface.
So I decided to build an ESP8266 ISP based on the NodeMCU board. I chose the original NodeMCU 0.9's programmer on two reasons:

  • It use CH340G chip, what is in SO package. The later ones use CP2102 and I still terrified of soldering the QFN package (I will try it once, I promise)
  • It has the automatic programming capability (RST, GPIO0 pins), mens I don't need to push buttons when I start the programming sequence

The original programmer use 5V to power the CH340G:

At the time I started to work on this project, it wasn't clear if the ESP8266 is 5V tolerant, so I felt it isn't a good idea to keep it this way. So I redesigned the circuit a slightly.
Here is my version:

I was able to manage to put everything to a single sided board:

and etch, build it at home:

It works like champ with my ESP8266 projects.