3D Printing on William Floyd (low-quality images)

Ghetto NAS Part 1

William Floyd — Tue, 29 Aug 2023 00:00:00 +0000

This is an ongoing project to build a custom NAS on the most minimal budget possible.

Use Case

Storing a large (30TB+) amount of infrequently accessed data that must still be immediately accessible (primarily Jellyfin, Nextcloud), with some level of safety.

Some details about my use case:

There will be no external network access except via a single local client mounting the drive and sharing via ZeroTier
There will be very few clients total
Most data is replaceable, though inconveniently so (media may be reacquired / restored from backups)
Neither latency nor throughput are very important

Bill of Materials

Quantity	Item	Per Unit Cost	Notes
3	Dell Wyse 3030LT Thin Client	$11	eBay - Fairly common, though may run out eventually - other thin clients will no doubt appear
3	HGST 10TB He10 510	$80	Amazon / eBay - Very common, can pick these up any day
3	ORICO 3.5in to USB enclosure	$25	Amazon - Could use another, this is what I chose, does the job for me
5	Ethernet Cables	$2.5	Amazon - $12.50 / 5 pack - Or whatever you have lying around
1	8 Port Ethernet Switch	$13	Amazon - Or whatever you have lying around
0.5kg	PLA	$20	For the NAS enclosure

Rationale

In order of importance for my use case: Price > Redundancy > Performance

Hardware

Thin Client

You simply cannot beat a whole working Linux box for $11. With 2GB RAM, 4GB eMMC, 1 GbE, 1 USB 3 port, and a bundled power adapter, it does the bare minimum I need.

Similarly, used enterprise drives deliver an amazing value. For less than $9 / T B o r j u s t o v e r$ 10/TB with the enclosure, these drives are the cheapest possible way to get storage right now. By using external enclosures we can also upgrade to larger drives in future, with minimal effort. No shucking required!

I buy ones that have a 5 year warranty (spoiler - it’s worth having!).

Networking

1GbE is plenty enough for me, but if in future I need more speed, I can find a network switch with 10GbE uplink and scale horizontally a fair bit. For now, a cheap unmanaged GbE switch will do just fine.

UPS

Not 100% required, but the peace of mind in having the whole system on a UPS is worth it.

Software

Gluster

I am using Gluster to run my NAS cluster. This is in large part due to its very modest hardware requirements, especially memory. I can run my nodes with less than 50% memory utilization, and not fill my limited eMMC storage either. It is very easy to work with, and offers flexible redundancy configurations.

Configuration

I am using Gluster with a dispersed volume, using the native client on my main server to mount the volume. Dispersed lets me add clusters of bricks fairly easily, which suits my needs well.

Netdata

This lets me know if/when drives get full, lets me know drive temperature from SMART data, and will email me if any hosts go offline.

Experiences so far

I’ve been too busy to document the whole process, but I currently have a 2 x (2 + 1) array running (if I’d known I’d need 6 drives, I’d have done 1 x (4 + 2), but I didn’t know at first). Capacity is 60TB raw, 40TB usable.

HDD Failures

That 5 year warranty I mentioned? I’ve needed it twice so far - one drive died about 1 month in, and a second died 2 months in. To their credit, the vendor got me a return package label within one business day each time, and refunded me as soon as the return package arrived. For now, I continue to use these drives because the $/TB is so good, but in future I may upgrade to some larger drives in the same way to keep power costs down.

Power Draw

6 x HDDs + 6 x Thin Clients + Network Switch + 12V Power Supply, draws about 40W at the wall under regular load (serving files).

Topology

Not shown in feeds: a Mermaid diagram, drawn by JavaScript. View it on the site.

$20 pen plotter

William Floyd — Sun, 26 Dec 2021 00:00:00 +0000

This was the final assignment for my second semester freshman engineering class (IEP 2). Budget given was $20, and my teammates and I decided a pen plotter would be a fun project. Here are some photos mostly of the final results

midiMixer - A simple Arduino powered MIDI potentiometer bank

William Floyd — Wed, 06 May 2020 00:00:00 +0000

This is nothing too special really - I wanted to try my hand at designing a custom PCB and assembling a device from scratch. GitHub for this project.

This story actually starts a while ago (perhaps 2015), when I got the desire to build a DJ control panel (with no knowledge of how to get into it). This never really happened, but it did lead me to get to know some DAW software, and experiment with it off and on. But in the back of my head I still wanted to build some hardware to help with this.

This eventually came about in the summer of 2019, when I finally hand-wired a simple 8 knob control surface. Truth be told, I actually built two. The first one had some issues (I wonder why…?), and would sporadically jitter values. The second one worked correctly, having been wired much more carefully.

Still, it was lacking professionalism, polish, and most importantly, robustness. The sandwich of 22AWG wire, cardstock and PCB was less than sturdy, so I promptly packed it away and never used it. Around this time also, I tried very briefly to learn how to use KiCAD, but didn’t get far at all. This would come to change, however, in April of 2020.

Fast forward close to a year, and here we are - toilet paper is the currency of the quickly collapsing Covid19 crazed world, and I’m back with my grandparents for the remainder of my semester (which, as of writing, is all but concluded). Finding my lack of a social life leaving me with a little bit more free time, and being home yielding a lot more distractions, I learned the basics of KiCAD from YouTube, and set out to design a simple PCB. My old MIDI controller project came to mind, so I set myself to it, and within a few days had my first Gerber files sent off to JLCPCB. In reality, I should have waited a bit and done a couple more design iterations before committing, but I guess $7 is the price of impatience.

So it was that my crisp PCBs showed up 3 weeks later - I had one assembled within the hour, and my old code dusted off and flashed within two hours. It’s really as simple as it gets - a Pro Micro hooked up to a 4051 analogue multiplexer, in turn hooked up to 8 potentiometers.

The potentiometers I had on hand ended up being a bit different than the footprints I had used, so I ended up having to clip the mounting tabs off of them. This, as one might imagine, made them extraordinarily flimsy, so I designed and printed a couple clamps to align and hold solid the potentiometers. These also have the added benefit of keeping the soldered pins off of whatever surface the mixer is on. Should the correct potentiometers be used, these would not be needed, though some feet or a case for the PCB would still be best.

This being my first PCB design, I am quite happy it worked out so well - I am studying for Mechanical Engineering, not Electrical… However, I see room for improvement. The potentiometers are too close together, and the rows are too far apart. The knobs barely clear the Arduino, and the Arduino is mounted far higher off the PCB than I would like. I see myself making a v2 in due course - perhaps next time I will try JLCPCB’s SMT assembly? I imagine adding indicator LEDs, improving the layout, and adding a button to switch between banks would make this much more useful.

Clickbait - The Automatic Fishing Caster

William Floyd — Fri, 13 Mar 2020 00:00:00 +0000

This project was completed in the Fall Semester of 2019, for my EPM class at LeTourneau University.

The mandate given to us was as follows:

Create a device to launch a fishing weight. It must:

be capable of selectively launching 20 and 40 feet
weigh less than 5 pounds
cost less than $100
be battery powered
be capable of firing 30 times over the course of 1 hour
(for extra credit) be wirelessly controlled

And so it was that we began brainstorming.

The idea was fairly simple - use two smooth rods and a leadscrew to pull a carriage against springs that would then somehow fire the fishing weight. The choice of this mechanism was, for the most part, due to availability of parts. I already owned the necessary rods and bearings, and springs were readily available.

Soon, we had some basic 3D printed parts in order - for it was 3D printing that was most accessible to us, and allowed largely unattended manufacturing while classes continued. Despite this early start of progress, however, the ever present tendency toward procrastination crept in. The usual array of excuses were made by all, and little actual work was accomplished.

So it was that we inched ever closer to the deadline. Past the basic idea of our launch mechanism, all else was yet to be decided. A few calculations were half-heartedly done (kinetic energy, spring constants, etc.), but we all knew we didn’t know enough to make any meaningful decisions yet. We had some very much unfounded fears concerning battery power, and not enough fears concerning torque - we believed we would be using NEMA 17 motors to tension the leadscrew. Needless to say, this did not turn out to be realistic. Nor was it realistic for us to budget a baitcasting reel instead of a much cheaper spincaster.

Eventually, however, some progress was made - progress in something of a wrong direction, but progress nonetheless. As the shape of our ungainly creation began to emerge, it was clear progress needed to be made quickly. Once we coupled our stepper motor to the leadscrew and power tested the unit, it was also clear that change was in order.

So a decision was made: a cheap cordless drill would be pilfered for a battery, motor and chuck. An H-Bridge would need to be bought for the drill motor (I tried to make one, but the magic smoke was released…), and a latching system needed to be made.

The next week or so resulted in the beginnings of a working launch mechanism. With the aid of a rubber band, a latching track was put under the rods and springs, such that the motor would tension the launching carriage, then return to the front of the mechanism to allow the eventual release of the catch using a servo. Soon after this, the motor was appropriately mounted to the frame, with a carefully fit 3D printed socket. It was, it seemed, all coming together.

▶ Watch the video

Finally, some success came to us. The motor was successfully power tested, along with the release of the launch mechanism. The end was near, or so it seemed.

Following soon after was the reel being mounted to the device also. Attempts were made to use a small DC motor, but with no luck. The lateral pressure of our motor acting through a belt meant friction was too much for our motor. Without time enough to reposition it, another solution had to be made.

Remaining at this point was a means of reeling in the line, a means of depressing the button on the rear of the reel, a limit switch at the front of machine, and the connecting electronics that would drive the entire contraption.

As it turned out, the very same stepper motor that had once tried to turn our leadscrew now instead would be pressed into service reeling in the line. Overkill, to be sure, and its power most wastefully used, it did indeed reliably turn our reel, albeit slowly. The use of such a large pulley was a matter of making it fit the belt size that I had available. The next size down was too small, so the pulley had to be enlarged. This saved the most time 3D printing as compared to a smaller pulley with other parts changed.

Finally, the mechanics of the project were completed, with each component individually power tested, though not yet in tandem with one another. As all of this was coming about, I had also begun getting the electronics in order. A limit switch was installed to keep the motor from destroying the machine. When this switch invariably failed to activate, it resulted in the destruction of the front piece of the machine - at that stage more of a nuisance than a disaster. Spares were kept by, and small changes were made so the switch could be mounted elsewhere in a more reliable fashion.

By way of a multi-button garage door opener, and a 433MHz receiver, wireless control could be granted to an Arduino for little money. A cheap buck-converter was added in order to run the Arduino and wireless setup, as well as the stepper motor driver. Thankfully, the voltage of the battery meant the stepper motor could be powered from the battery directly (18V being safely within the rated 12-24V range)

▶ Watch the video

In the above video, the finished product may be seen.

Finally, presentation day came. Not without some small failings, we presented, with acceptable results. The largest remaining issue was the fact that the leadscrew would slip the grasp of the chuck after several cycles of the machine. While we corrected by hand for the presentation (by re-chucking the leadscrew after each launch), we knew we needed to fix the slippage for good. After all, the final time-lapse of the project would not do with such continual, and blatant, hand-holding.

The solution, it turned out, was free: the end of the leadscrew was notched and tapered on a lathe, allowing the drill chuck to get a firm hold on the metal.

▶ Watch the video

With this solved, the final time-lapse was completed, and a collective sigh of relief was given.

Much was learned - how to more properly budget for a project, how to work with a team (something I need to improve on), and how to manage time well. All things considered, I found it to be a success - I did not pull an all-nighter for my own project, finishing with a few days to spare (no small thanks to an extended deadline), nor did I stress myself beyond all reason. Overall then, I enjoyed the experience of finally bringing a project to completion - this is something I do not often do, try as I might. The result, though useless for my own purposes, is something I am proud of, having taught me many things through its completion.