It's a reboot, not a sequel.
While a full-sized machine (ie. X and Y dimensions are 21" or bigger) is still part of The Big Picture, I've come to the decision that a small cartesian unit dedicated to burning out PCBs is where I really need to start.
WAIT, WHAT? WHY?
Tough crowd. I have a monster custom music workstation/performance controller that I've had in my Bucket List of music gear projects for about 15 years, and things have aligned to a degree where I can finally start getting the thing built. (See my latest posts in the "Between Me an Rangerboy" thread for the details there.) The challenge I have in building the monstrosity is the circuit boards needed for the microcontroller(s), as well as the digital and analog i/o matrices. I have a source on finished, ready-to-populate boards, but the guy is out with no ETA on new stock. Great.
Thus, I must fabricate my own. I want to use a dedicated CNC router for this because I want nothing to do with the traditional "laser printer + ferric oxide etching" DIY process. I live in an area where disposing of the used etch chemicals is impossible (no sewer system - septic only). Additionally I want to do this process in my house.
Having my own PCB rig will allow me to make my own no-longer-in-production open source synthesizers as well, such as the Mutable Instruments Ambika 6-voice analog, plus other electronic projects that I may discover or design on my own.
UGH! WHAT ABOUT THE BIG CNC, YOU SELL-OUT?
Jeesh. It's still happening, but during the time of metaphorically putting everything on the shelf my options have become more vast and diverse, and I really don't have the time to build one from plans. The Momus is a great looking tool, but I need something I can pull out of a box, spend no more than a day or three assembling, and then start using the mutha. I've narrowed it down to the Shapeoko 3 XXL and the Stepcraft 2/840. I'll talk more about it in a later post.
There are only two.
1. Size. It has to be able to share space on a table with other electronic equipment in my work area, which is somewhat limited. Since I don't plan on kicking out PCBs that are any bigger than 6" x 4" this isn't a major issue.
2. Cost. This above all other factors limits me the most. Fully outfitted, I can't justify spending more than $600. So no Carbide3D Nomad or Othermill Pro for me, although either one would be the Dream Machine for this purpose.
Chinese 2020 CNC:
Definitely the least expensive and easiest to obtain mini CNC machine around. Probably sold under 30 different names in the USA alone. Everything, including the 300W spindle and drop-shipment from China, is about $400. The downside is the quality of everything. The electronics, while cheap and easy to replace, are often total trash. The linear bearings are also often wrecked out of the box as well. The user has to refurbish the thing before they use it the first time, so I'd have to figure in another $200 for the machine's "restoration budget." On the other hand, if properly tuned up it may prove to be a formidable tool. Just not sure I can rationalize risking the $ to find out.
Cyclone PCB Factory, v2.1 or newer:
The one that gets me the most excited. 100% open source. Its plastic parts are all 3D printed, and if I go this route I'll either need to buy the parts from a printing service or snag a printer of my own (which I need to do anyway - will start with something Prusa i3 based). The stock spec is approx. 8" x 4" x 1", but I can alter this to anything I like by just changing the length of threaded rods and sliding rods in the construction process. I might also see if I can get short lengths of Acme thread or threaded ball rod and use it instead of standard 8mm threaded rod. I'd also omit the 125W Dremel 3000 for a Chinese 300W 52mm air-cooled spindle. They're quieter and cost the same $. However, I'd probably have to redesign the spindle mount, so maybe the Dremel is okay for the first few weeks of operation.
One of the cool things about this unit is the vacuum connection - that's what the two lengths of surgical tubing is all about. I'd have a household canister vac connected to the junction piece as the CNC runs to limit the amount of copperclad that gets thrown into the air and onto my work surface.
I did find an eBay seller based in the US who sells complete Cyclones (I just get my own spindle and PSU) but he refuses to respond to the couple of simple questions I've asked. Big red flag for me. There's also a retailer Stateside that supposedly has these, but their store is offline. Another red flag. This is why I'm thinking I need to maybe snag a decent 3D printer and churn out the parts myself. That route actually means that this endeavor could equal 3DP + CNC to make the PCBs for my bigdang keyboard, meaning that instead of having a $600 budgetary cap, it may have to be $1,200 to $1,500. Not that I don't need the extra tools, but it's definitely a case of snowballing or feature creep.
I just discovered 3DHubs.com, where I can find "local" 3D printing services and get a quote from them. Therefore, to get my PCB CNC running I don't need to buy a 3D printer first. Sweet.
I got a quote for all of the parts in ABS. Only one print service in the state will do ABS. Thankfully, it's also the highest rated. Less than $75 for all the plastic parts based on the .STL files I uploaded to get the quote. Might do it as soon as mid-August.
The largest work area of the units in my list of candidates: 13.5" x 11" x 6". Also the most expensive: $610 for the hardware only + NEMA 23 steppers (which are overkill for my needs), $130 for the driver/controller, and $50 for the PSU = $780 before I even get a spindle (which would be a loudassed 2hp production router motor) and cutting bits. The cost and size actually could disqualify it from consideration altogether, so maybe I'll forget this one entirely. If I was spending this kind of money, I'd rather get a standard dimension Shapeoko 3.
Forget the Openbuild unit. It's either the Knockoff knock off or the rig that requires me to get a 3D printer too. Both are small enough that I could put them in a well insulated enclosure to further dampen noise, and I should still have room for my soldering station, testing PSU and regular paper printers.