Karl Johnson, Author at CNX Software - Embedded Systems News

December 7, 2018May 11, 2021 by Karl Johnson - 6 Comments

Geeetech A20M Review – A Dual Extruder, Color Mixing 3D Printer

Hey Karl here with a 3D printer review. I know it has been a while for a printer review and grateful for Gearbest sending the review unit. They shipped me the Geeetech A20M a single nozzle, mixing, dual extruder 3D printer. Man that was a mouth full. It is a follow up to the A10M which is similar but a smaller build volume. The A20M clocks in with a 255x255x255mm build volume. My last foray with a multi material printer was a Tevo Tarantula and it was mildly successful. I didn’t realize that this was a mixing extruder and the implications. I have done some very cool looking prints due to the fact that it’s a mixing extruder. QC Issues I always come to expect some QC issues with these low cost printers. But I have to say that this printer has had the most. Let me list with fixes […]

October 3, 2018June 19, 2019 by Karl Johnson - 2 Comments

Genmitsu CNC Router Review – Part 1.5: Laser Attachment

Hey Karl here with a small update for the SainSmart Genmitsu CNC Router 3018 review. In the first part I described the build and first cuts. And in this part I am calling it 1.5 because it is to just talk about the optional laser attachment that was just made available and initial impressions. In the first part I commented about the laser connector on the board. The stars aligned and Sainsmart asked if we wanted to check out their 2.5W PWM controlled laser sold for $89.99 with free shipping. Installation In the box all you get is the laser itself and some eye protection. At first I wanted to mount the laser on the side of the tool head so it would be easy to change between CNC and the laser. I took the laser apart and was going to use the 2 mounting holes and ended up breaking […]

September 19, 2018June 19, 2019 by Karl Johnson - 33 Comments

Genmitsu CNC 3018-PRO CNC Router Review – Part 1: Build & First Etches

Hey Karl here. Today we are going to look at something a little different. I am writing about my experiences with building Genmitsu 3018 CNC router upgraded version provided by Sainsmart for this review. While waiting on the unit to arrive I did some research and found that there are several different versions on the market labeled CNC xxxx. The xxxx represent the build volume in the x and y. So the one I was sent has a 300x180mm build volume. The 3018 is called upgraded because the new mounting for the X and Y rods and lead screws. On the previous version these had to be mounted and manually aligned which from what I read can be a pain. Building Genmitsu CNC 3018-PRO CNC Router The build went very well. The 3018 user manual was mostly pictures but they called out anything that might be questionable. I had been […]

June 20, 2018June 20, 2018 by Karl Johnson - 1 Comment

YouTube Streams 1 & 2 Update, Plus Quick Fix for Uneven X Gantry

Hey Karl here with an update on the YouTube Live streams from last week. Live Streams Update The 1st stream went about as well as I expected….Not very well. I was really nervous and I broke the live link that was posted on here at the last minute. My whole reasoning for the Livestream was to show the processes in real time and not do too much footwork ahead of time. On the first one I was planning on migrating from Marlin 1.1.6 to Marlin 1.1.8 but I had already done lol… So I ended up migrating to the bugfix branch which presented additional challenges. Overall it was successful and I hope I conveyed the process. I was able to get it to print but I ended up going back to 1.1.8 due to some error in the bugfix branch that caused weird jittery movement. I will in the future […]

June 13, 2018June 15, 2018 by Karl Johnson - 6 Comments

LiveStream #1 – Migrating to Marlin Firmware

Karl here. I’ve decided to start doing a weekly Livestream on different topics related to subjects covered on CNX Software. For the fist livestream, I will be showing the workflow that I use to migrate to newer Marlin firmware on HE3D K280 3D printer but it applies to any printer. I will also cover the calibration process for the K280. I originally did a written review of the K280 but it is sometimes hard to show concepts in writing. The livestream will take place on June 14th @ 21:30 ET timezone, and if you are interested you can register below, or come back to this page to check it out. Karl JohnsonKarl is a technology enthusiast that contributes reviews of TV boxes, 3D printers, and other gadgets for makers.

May 10, 2018May 10, 2018 by Karl Johnson - 1 Comment

Two Interesting Projects on Github: Zigbee to MQTT bridge & “Deep Painterly Harmonization”

Hey Karl here. I thought I would try and showcase some GitHub projects that I run into that seem interesting or fun. This week I will start out with 2 projects. Zigbee to MQTT bridge The first one today is a Zigbee to MQTT bridge. Previously we did a couple articles with 433MHz bridges for home automation, a diy RF bridge and one by Sonoff. This bridge is similar but with Zigbee. Unfortunately 433MHz typically have one way communications, and when a message is sent there is no response and the system has to assume the message is received. Zigbee is a 2 way protocol and an acknowledgement can be sent back. The code is moving fast right now and blowing up my GitHub notices. It is a little bit of a mystery on how this works right now with the parts list, but seems to be working for some […]

April 26, 2018April 26, 2018 by Karl Johnson - 9 Comments

How-to Make Your Own 3D Printing Goo

Karl here…just want to do a little post about bed adhesion and what I have been doing for the past month. What spurred this is I saw a ton of videos on Magigoo a while back. It is a product that you wipe on your glass/mirror bed and 3D prints stick very well to it and once the bed cools the part pops off very easily. It is quite expensive and it got me to think about alternatives. I have used glue stick almost exclusively while printing on glass/mirror but a lot of time the prints stick too well and prints can get marred up removing with a tool. It is quite easy to make. 1 cup water and 1 large 22g Elmers glue stick. I put both in water and let sit thinking it would dissolve on its own. After several hours I got impatient and put it in […]

April 26, 2018 by Karl Johnson - 12 Comments

Working on High Quality Low Cost DIY 3D Scanning using Structured Light

Hello all, Karl here. I just wanted to send a note about what I have been working on. As the title says shows it is about 3d scanning. I have found it pretty fascinating so far. These are mainly based on structured light 3d scanning. From Wikipedia: Structured light is the process of projecting a known pattern (often grids or horizontal bars) on to a scene. The way that these deform when striking surfaces allows vision systems to calculate the depth and surface information of the objects in the scene, as used in structured light 3D scanners. There are a few commercial offerings that I have run across or have found while searching around but they are very expensive. The first one I ran across was made by Einscan. They are over 1k and have been reviewed a lot. It seems like they put out a good product and keep […]