Wednesday, 25 January 2017

Getting ESPlorer to Run on Mint 17.4

I was having problems getting ESPlorer to run on my Linux machine , this to program an ESP8266 Wemos D1 Mini Clone with Lua , html content and an HA Bridge running on a Raspberry Pi for use with an Amazon Echo to control some RF remote control mains sockets. The error displayed from the console was  :-

 # A fatal error has been detected by the Java Runtime Environment:
#  SIGSEGV (0xb) at pc=0x00007fe595a40009, pid=11774, tid=11803
# JRE version: OpenJDK Runtime Environment (9.0) (build 9-internal+0-2016-04-14-195246.buildd.src)
# Java VM: OpenJDK 64-Bit Server VM (9-internal+0-2016-04-14-195246.buildd.src, mixed mode, tiered, compressed oops, g1 gc, linux-amd64)
# Problematic frame:
# C  []  JNU_GetEnv+0x19


I used the command :-

sudo update-alternatives --config java  
and had the choice of either java-8-openjdk-amd64 or java-9-openjdk-amd64 on my machine. The default was java-9-openjdk-amd64 so I selected java-8-openjdk-amd64 and ESPlorer then worked without issue , I hope this helps someone in the same position.

Thursday, 18 August 2016

3D Printing PLA Not Sticking

I have found that using blue masking tape works for helping adhesion of PLA on heated build plate. Though the brand I bought was not very good in that the print wouldn't stick to the plate. 3M blue masking tape is apparently the best for this. While I waited for this tape to arrive I used hairspray sprayed onto the glass build plate , this provided good adhesion for my prints. I like the idea of the blue tape as it's less messy than the hairspray method. 

CTC Replicator 1 (Dual) Clone RFI problems

Occasionally the display on this printer becomes garbled and the reset has to be pressed. I also noticed that when this printer is on it affects the speed of my fibre to the cabinet FTTC broadband. As a licensed Radio Ham I did notice that there was little or no RFI (Radio Frequency Interference) filtering at the mains input or any ferrite sleeves over wires going to the motors and thermocouples etc. I think that the switchmode power supply is probably causing RFI to be transmitted along the mains and then it's being picked up by the telephone line so reducing the broadband speed. I will retrofit filters and ferrite's to reduce the noise made by this machine. The graph below shows the slowing effect of this printer on my broadband speed.
I have since moved my printer to another room away from the telephone line until I get it filtered better.
WARNING! modifications to your machine may damage it or cause a FIRE! you have been warned. Be CAREFUL with Hot things like your printer!

CTC Replicator 1 (Dual) Clone Printing Issues Still!

I continued to have printing issues and it took me a while to solve. I found that the filament drive stepper was clicking all of the time and had got worse over time. I had disassembled the hot-end many times but nothing seemed to help. I then compared the hot-end channel 1 with channel 0 and noticed that the heater block was loose on the hot-end feed tube on channel 0. This meant that the block was heating up ok and the temperature was reasonably accurate but the heat transfer to the hot-end was very poor. This resulted in me having to turn up the heat to around 250 DegC to get any amount of flow from the nozzle. So I tightened the feed tube onto the heat block and re-assembled everything , immediately it began to print like new again. I was able to back off the digipot values to 118 from 122 on the printer settings and no feed clicking was evident during extrusion. Happy days!
 WARNING! modifications to your machine may damage it or cause a FIRE! you have been warned. Be CAREFUL with Hot things like your printer!

Friday, 12 August 2016

CTC Replicator 1 (Dual) Clone Extruder Clicking

My CTC Replicator 1 Clone (dual extruder) which I had for a good while and had done some really nice prints , then eventually I couldn't print anything. It would feed filament in a stop start fashion usually ending in a big bundle of filament. The symptom was the right extruder stepper drive just clicked when trying to drive filament though the hot end. I dismantled the 0.4mm nozzle and heat tube and found no blockages. I then set the extruder in motion heated but without the nozzle and it was still clicking while driving. It just seemed that the stepper motor didn't have enough torque to drive the filament. I looked around the interweb and there were mentions of digipots for controlling the drive current. So I connected my laptop via USB to my 3D printer and fired up the Makerbot Desktop software and  looked at the digipot settings under Devices -> Device Settings , the setting for digipot A was 118 so I increased this to 122 ,  the maximum is 127. While I was there I changed the setting for channel B to 122 as well just in case its stepper drive had the same problem. I tried driving the filament again but nothing changed click , click , clicking Hmmm! I then pressed the reset button and this time when I drove the filament stepper there was no clicking ,  result! It appears that any changes made to the Device settings are only read in on boot so even if you change something the old value is still used until you press the system reset button whereby the settings are read in from the eeprom.
WARNING! modifications to your machine may damage it or cause a FIRE! you have been warned. Be CAREFUL with Hot things like your printer!

Friday, 5 August 2016

Makerbot on OS X Stuck in Fullscreen Mode!

I have had trouble with OS X El Capitan Version 10.11.6  and Makerbot Version Once you have entered fullscreen on Makerbot you will not be able to go back to the windowed version using any of the standard key combinations like esc and the ctrl + cmd + F key , it will just plain not work. To fix this from the terminal , first create a copy of /Users/your_username/.config/MakerBot/MakerWare.ini something like MakerWare.ini.orig , then edit the MakerWare.ini file using vim and look for  the WindowGeometry="..........." entry. If you remove the data after the = including the quotes " and replace it with default ( it should look like this WindowGeometry=default). Then save it , when you start Makerbot it should start back in windowed mode - hooray!!! I took ages to find out how to fix this , even forums acknowledged it was a problem but gave no solution , the fix worked , go me!

Monday, 18 May 2015

Poor Man's Through-Hole PCB Rivet

First of all I have to thank Retromaster for his descriptions on how to do through-hole contact riveting. My double-sided prototype PCBs are done on a CNC Router but originally I was using just flexible wire soldered on both sides of the PCB. This method I found just created big solder bumps , not much good for surface mount IC's with through-hole contacts directly under them. So to remedy this situation I used a drill press with a 3mm stainless rod mounted in the Chuck. I put short pieces (approx 2.6mm long = thickness of PCB 1.6mm + Protrusion on each side of PCB 0.5mm X 2  ) of tinned copper wire whose diameter  matches closely the diameter of the via hole into the via for the through-hole connection. I positioned the 3mm rod in the chuck over the via to be riveted with the copper wire in the hole and gently rotated the drill press capstan. This pressed the copper wire into the hole. I relaxed the pressure on the PCB to allow the balancing of the head size of the rivet on both sides of the PCB. Below is a photo of some practice rivets and one via not riveted on a scrap PCB for practice, these rivets will have a light soldering using solder paste to ensure a good electrical connection. I am very pleased with this method of connecting vias on PCB prototypes.

Riveted through-hole connections