Fabrication Lab: Perfecting the Craft

Between ice hockey, Lego's, portable radio operations and my job at The University of Chicago that makes all this possible, you may have forgotten that I maintain a 3D printing hobby. I have a whole section of my blog, "Fabrication Lab" dedicated to it. So, I thought I'd write a post returning to my 3D printing hobby. 

My latest adventure in 3D printing was not so much about the models and prints themselves, but fine-tuning my printer. I had a problem, a small problem, but a problem none-the-less: My prints had lines in them. They printed successfully, but they were imperfect. They had lines of filament that were skipped, meaning that there were visible imperfections in the final product. 

The top two boats have "lines". The bottom one is perfect.

For weeks, I couldn't figure out the problem. I tried making a cool looking Tiki mug for my friend, but it kept coming out of the printer with lines. In other words, it wasn't as nice looking as it could have been. I finally gave my buddy his imperfect Tiki mug, and while he still loved it, I felt bad because I knew a Creality K1 Max should print better than the product I was able to give. And, if it were something more than a Tiki mug, I wouldn't want flaws in the filament layout... especially if it was a load-baring object. 

I took some time over winter break to experiment with my printer. I didn't know what was causing the lines (imperfections). I tired adjusting a number of variables: I used different filaments (from PLA to ABS) , I tried heating the build plate (from 50 degrees Celsius to 80, and then to 100 degrees), and I also replaced the 0.4 millimeter nozzle on my K1 Max. Nothing helped, regardless of the temperature or settings I adjusted, the prints were coming out imperfect.        

The nice thing about having a Creality printer, though, is that they have an open-sourced plan, with easily replaceable parts. I was at my wits' end, and I didn't want to cut open a $1,000 dollar machine and risk breaking it... But what good is a printer that can't print perfectly? 

I logged on to YouTube, and watched some helpful tutorials on how to replace the extruder for the K1 Max. It turns out, it was easier than I thought. You need to be very careful to keep each piece, and document the deconstruction so you know how to put it all back together. However, outside of that, it's basically just a matter of following directions. 

When I dissembled the extruder, I found the problem. The gears that pull the filament into the heater and then lay them onto the build plate had a flaw. Some of the claws in the gears were worn down. I believe it happened when I used a metal wire to force out a filament clog. I fixed the clog, but in doing so I damaged the gears. Each time the gears and filament met at the damaged part, the K1 stopped extruding. It still made the full prints, but those prints had visible lines where the material was not laid down. Those tiny imperfections in the extruder gears led to tiny imperfections in the final prints.        

Luckily, I had a Creatily printer which (at least for now) supports tons of parts, modifications, and third-party enhancements. I bought myself a completely new extruder with good gears for 26 dollars on Amazon. There were plenty of YouTube videos to help me complete the installation, and it was mostly painless. 

The most important thing is that I was able to get my K1 Max (which I have a lot of money invested in) printing perfectly again. All it took was a replacement part costing 26 dollars, and some workshop tools like a screw driver.      

The Creality K1 Max

All in all, it ended up being a fun and engaging experience. While I would've wished my K1 kept printing perfectly without any repair needed, it didn't. I used the opportunity to figure out how to repair her! 

It did cost a little bit of money, but 26 bucks is nothing compared to buying a whole new printer: a K1 or any other brand. I also believe this speaks to Creality's commitment to the "open-source" model. Creality printers let us users use any software we'd like, and open their own equipment up to third-party replacement parts. So, us consumers can keep our equipment, design our prints, and (importantly) repair our own machines at a reasonable cost, with Creality parts or with third-party parts. 

MicroSwiss, for example, is an excellent third party part-maker for 3D printing. And they have parts that work with both my Ender 3 and K1 Max. While Creality provides quality replacement parts themselves, I'm glad their machines are compatible with other firms' products. It's truly good for the industry, and for hobbyists like myself!    

My Yaesu FT-891 Modular Rig Set-up

The radio

The Modular "Cubbyhole" rig

As a rookie member of the amateur radio community, and recent technician licensee, I’ve been looking to move forward in the hobby. Having contested with the PCARS/K8BF crew, I knew there was more fun ahead by investing in an HF transceiver and equipment.

 

I mastered two meters well before I even moved to Ohio and joined PCARS, so I know the real fun is in HF. I’ve had the opportunity to contest on SSB for many bands outside of my license permissions with PCARS, and I’m hooked! Not only that, but I’ve received a lot of good advice from the club members. So, the question was what HF radio to get?

 

I love the ICOM IC-7300 radios available at our club site, and I got plenty of suggestions online and from club members. However, I couldn’t find too many decent trustworthy used options with the capabilities of the ICOM IC-7300. Not only that, but the bulky frame of what I consider to be a base station transceiver takes up too much space for me. I’d like an HF radio that I can use at home, then throw in a backpack for a POTA activation on short notice. Additionally, I’d like something I can take easily with me to a new home or apartment if I decide to move.

 

My solution was the Yaesu FT-891. It’s compact, well regarded and it retails new for about $800. I couldn’t find a decent used ICOM or Yaesu for less than $600, so I figured I’d buy it new direct from the manufacturer. I follow numerous DX’ers and POTA adventurers on social media, and the FT-891 was a popular choice for portable operating, especially in the UK and Europe, so I was confident in the decision. 

End-Fed 10m Antenna

I was not disappointed. When I opened the package and set up the little rig, the settings and capabilities of the Yaesu seem to rival a larger, more-expensive, base station. It offers SSB, digital modes with CAT control, RTTY and CW, an easy menu for selecting power output and various settings -which can be saved specifically for each mode- internal tuning, noise control options, and a variety of other features. Its only drawbacks, in my mind, are that it doesn’t offer a very good scope for waterfall visuals -which can make viewing band activity difficult on a slow day-, and it does not offer UHF and VHF -which is fine for me because I have my ICOM IC-2730, which handles UHF and VHF very well for me already.

 

In about a day, I had strung up an end-fed half-wave 10 meter antenna with a 9:1 balun, and made my first SSB contact on my own rig in the UK with only 40 watts! I could hear my counterpart great, and he reported hearing me at about 57 out 59 (pretty good) in southern England. So, the FT-891 works like a charm for my needs.

 

The modular set-up

 

Earlier, I mentioned I wanted a somewhat compact rig set-up -a hybrid base station that can easily be used for portable operations when needed and wouldn’t be too much of a hassle to take with me if I move soon. So, I came up with a modular design. I bought these little metal desk-sized shelving risers from Amazon and created a four-slot “cubbyhole” shelf for the rig. On the left side, I have my VHF/UHF unit with the ICOM IC-2730 as well as my Uniden digital scanner. On the right I have my HF unit with the Yaesu FT-891, an LDG antenna tuner, Signalink box, and SWR/power meter. Each side has its own DC power supply, so even if I pull out the FT-891 and use it elsewhere, my tried-and-true UHF/VHF set-up is still operational.

 

In the back, I’ve cut and crimped all the wiring to exactly the lengths I need and also saved some pre-cut jumpers for when I need to change locations or re-organize. Each rig has its own antenna system, with grounds for both lightning-arresting and electronic noise reduction. So, again, the idea is that each “unit”, the Scanner unit, the UHF/VHF unit and the HF unit can all be pulled, taken away, and plugged back in when needed.

 

To the right of my rig, I’ve got my laptop which is obviously portable in-itself; but, it fills one important gap in my existing set-up: I use an RTL-SDR.COM V4 USB dongle along with SDR ++ to get a visual waterfall of the HF bands while using the transceiver. This makes up for the small display on the Yaesu FT-891 as well as the built-in scope, which leave a lot to be desired. So, the SDR dongle and laptop really add-in the features of a more robust base-station. I also use the laptop for digital modes on the F-891 such at FT8, and for stand-alone SDR projects, like connecting to NOAA satellites and home-made air-traffic control.  

 

3D-printed storage drawers

Lastly, a small feature, that I’m proud of none-the-less, are the three 3D-printed drawers I built to fit right into the gaps remaining in the shelving. They fit all the adapters, USB cables, and little pieces of hardware all HAM’s need to have around. Having lived in city apartments for almost 15 years, I’ve learned to really appreciate space and storage management, and if I keep going to HAM fests, I’m going to need it!

The Joys of Ice Hockey

When I was a schoolboy, I had a particularly crabby English teacher. If she wasn't giving long-winded lectures on topics unrelated to the books she assigned, she would sit at her desk and observe us while we read the book ourselves.

During one of these "reading" periods, I happened to fall asleep at my desk. I woke to that teacher slamming a hardcover book on the desk... the desk on which my head was resting. 

"I'm sorry" I said,"I had a hockey game last night, and I'm kinda tired." 

She snapped, "What's more important to you, Stephen? School or Hockey!" 

"Do you really want to know the answer?" was my reply. 

It was, of course, hockey.

That day, I made an enemy of that teacher. But, I made a classroom of friends (most of them were at that game). 

It seems like ice hockey was in my blood from a young age. Even though my parents didn't play themselves, they took me to Kent State NCAA Division-I hockey games as a kid, because we happened to live very near an ice rink in Kent, Ohio. My father actually got to be an extra in the film Slapshot which was filmed in Johnstown, Pennsylvania. I played in a tournament in that same rink more than a decade later.

I could go on at length about my hockey stories... Meeting the legendary Czech, and hall-of-fame Pittsburgh Penguin, Jaromir Jagr; Billeting in Embro, Ontario for a US-Canada Hockey exchange; and playing on the ice of Nationwide Arena, home of the NHL's Columbus Blue Jackets. But, I digress.... 

Basically, in my younger years, I was a pretty good hockey player. Not great, but good. I believe my peak was going to the Mid-American USA Hockey Development Camp tryouts. It was a big deal. I even got to skip two days of school to travel to Toledo, Ohio to participate. I didn't really have any goals in-mind other than to do the best I could, and get some extra skating time in. Yet, I found myself skating, and competing with the best hockey players of my age-group. They towered over me and out-weighed me. I knew I was not going to be selected from the first minute I stepped on the ice. But, I participated, and I actually made some good plays -enough to get a nice pat on the shin pads from my bench-mates, and a slap on the helmet from a few coaches. 

I didn't get selected. Afterwards, I was more tired than I have been my entire life. I was glad I did my best, and I skated with future NHL and AHL players. I could share the same rink with them, and get their acknowledgements when I did make a (rare) nice play. And, when I went back to playing high school hockey, I played like I was on fast-forward, and the rest of the players were on slow-motion. It was one of the best learning experiences I've ever had in any subject, professional or otherwise.

When we valiantly bowed out of the OHSAA playoff to a far-superior team my Senior year, I was more relieved than sad. There was college and marching band to look forward too; but mostly, I was grateful that I never had to do another practice, sprint or conditioning drill ever again. With my evenings free, there lay ahead of me a multitude of possibilities: jobs, colleges, girls, partying, golf? They all seemed a lot better than watering the ice rink with my sweat. So, that was it, I gave-up hockey.

Wish me luck, boys.

Yet, I miss the salty smell of sweat on my fingers. It lingers after games and practices, even when you've showered and and scrubbed with soap. I miss the smell of the rink, and the flavor your car gets after hauling hockey pads around all week. I miss the calluses that build up on your palms from tightening your skate laces each night. And, I miss the boys. My teammates. 

Apparently, hockey is, in-fact, in my blood. Because, in-spite of all logic, at 38 years of age,  I have signed up for an upper-level men's league hockey team. According to my doctor, I'm overweight and have high blood pressure. I'm pretty sure I can't jog a mile without stopping, and I have aches and pains that happen randomly whether or not I workout. 

Could hockey really be the answer? Could it really be better than eating healthy, taking my doctor's prescriptions, and having a brisk walk every morning? 

Do you really want to know to the answer? 

I'll let you know after our first game.