The build is documented over a series of nearly a dozen YouTube videos, the first of which was put out all the way back in January of 2020. Seeing [Bob] heading to the steel mill to get his frame components with nary a mask in sight is a reminder of just how long he’s been working on this project. He’s also put together a comprehensive Bill of Materials on his website should anyone want to follow in his footsteps. Coming in at only slightly less than $4,000 USD, it’s certainly not a budget build. But then when we’re talking about a machine of this scale, nothing comes cheap.
Even if you don’t build you own version of this router, it’s impossible to watch the build log and not get inspired about the possibilities of such a machine. In the last video we’re even treated to a bit of self-replicating action, as the jumbo CNC cuts out the pieces for its own electronics enclosure.
You can tell from the videos that [Bob] is (rightfully) proud of his creation, and isn’t shy about showing the viewer each and every triumph along the way. Even when things don’t go according to plan, there are lessons to be learned as he explains the problems and how they were ultimately resolved.
For years, [Michael Davis] has been using a large lead-acid battery to power the electronic components of his custom Dobsonian telescope; but that doesn’t mean he particularly enjoyed it. The battery was heavy, and you always had to be mindful of the wires connecting it to the scope. Looking to improve on the situation somewhat, he decided to build an adapter for Ryobi cordless tool batteries.
[Michael] had already seen similar 3D printed adapters, but decided to make his the traditional way. Well, sort of. He used a CNC router to cut out the distinctive shape required to accept the 18 V lithium-ion battery pack, but the rest was assembled from hardware store parts.
Bent mending plates with nuts and bolts were used to create adjustable contacts, and a spring added to the top ensures that there’s always a bit of tension in the system so it makes a good electrical contact. This setup makes for a very robust connector, and as [Michael] points out, the bolts make a convenient place to attach your wires.
With the logistics of physically connecting to the Ryobi batteries sorted out, the next step was turning that into useful power for the telescope. A stable 12 V is produced by way of a compact DC-DC converter, and a toggle switch and fuse connect it to a pair of automotive-style power sockets. Everything is held inside of a wooden box that’s far smaller and lighter than the lead-acid monster it replaced, meaning it can get mounted directly to the telescope rather than laying on the ground.
More importantly, the connector [Charles] produced looks fantastic. If we weren’t told otherwise, we’d have assumed the finished product was commercially produced. Although to be fair, he did have a little help there. The housing and pins themselves were pulled from a sacrificial connector; his primary contribution was the insulating block that holds the pins in their proper position.
So how did he make it? He had considered using a piece of scrap material and just putting the holes in it with a drill press, but he was worried getting the aliment right. Instead, he decided to call his cheap CNC router into service. By routing his design out of copper clad PCB, he was even able to tie the appropriate pins together right in the connector.
Sure, but [Michael] realized that simply cutting out a ring wasn’t a very efficient approach. Unless you happen to need progressively smaller plant hangers, or maybe a new set of drink coasters, the center disc ends up being wasted material. That might not have been a big deal a few months ago, but when a trip to the Home Depot for more plywood could literally be hazardous to your health, that kind of inefficiency just won’t do.
He reasoned it would be better to break the ring down into sections, which could easily be nested so they fit neatly on a square plywood panel. Of course, now those sections need to be connected to each other in a way that’s strong enough for the ring to hold up the weight of the plant.
So that means extra pieces need to be cut out to serve as braces, and you’ll need to screw it all together, so better add some nuts and bolts to the BOM. You’ll probably want some eye bolts as well, but in a pinch you could just weld washers to the heads of screws like [Michael] did once he ran out of the good stuff.
Some would argue that the time [Michael] spent coming up with this revised design is more valuable than the wood he avoided wasting, which might be true if he was on the job and getting paid hourly. But when it’s a personal project, and quarantine has made sourcing materials difficult, we think it’s a fantastic example of working with what you’ve got on hand.
[Adam Haile] has been spending some time improving his CNC router and his latest change is a custom wasteboard with improved bed support. Not only does the MDF wasteboard have plenty of threaded inserts to make for easy clamping solutions, but [Adam] replaced the frame underneath the board with a new set of aluminum extrusions to provide better support. Originally, there was only support for the edges of the wasteboard, which allowed the middle to sag. While researching the machine’s specs, he was able to recognize and order the exact extrusions he needed from Misumi and construct an improved bed to go with the new board. Should you wish to make your own version, [Adam] provides all the part numbers and CAD files required.
Embedded below is a video showing the machine drilling the holes, followed by surfacing the entire board so that it is flat. Since the bolt heads are well below the surface of the board, and the threaded inserts for the holes are on the bottom, there’s no worry of the tool hitting anything it shouldn’t during this process.
If you’re looking at CNC machines, or machine tools in general, heavier is better. That old drill press or mill made of a few hundred pounds of cast iron isn’t just better because it’s stood the test of time for a hundred years — greater mass equals less vibration. Thanks to modern epoxy resins, we now have a replacement for tons and tons of iron. Epoxy granite, or chips of granite bound together with epoxy resin, is a viable and very good base for CNC machines, mills, and other tools that are served well with a ton of mass. [Joerg Beigang] is building his own CNC router, and he’s building the base out of epoxy granite. Here’s how he’s doing it.
Before you pour epoxy into a mold, you’ll need to figure out how you’re going to attach your ways, linear rails, and ball screws. [Joreg] is bolting these parts to pieces of aluminum he cut on his home made panel saw before carefully drilling and tapping them to accept the linear rails. These aluminum plates were then mounted to the bottom panel of the mold, in this case melamine-coated plywood.
As you would expect, the most intricate part of this build isn’t globbing up a mold with epoxy resin. No, the real trick here is making sure the rails of the CNC are aligned perfectly before the epoxy goes in. This was done by bolting the linear rails to the mold box and checking everything with a dial indicator. Once that was done it was time to pour.
The bed itself is made of 18kg of epoxy granite, with the entire pour done in four batches. The best way to settle a big pour of epoxy granite is through vibration, just like concrete, but it looks as though [Joreg] is getting some good results by tamping it down with a few sticks. You can check out the first part of this build series below.
Trying to make a hemispherical surface out of a PCB is no easy feat. Trying to do that and make the result a working circuit is even harder. Doing it with one solid piece of FR4 seems impossible, right?
Not so much. [brainsmoke] came up with a clever way to make foldable, working PCBs that can be formed into hemispheres. The inspiration for this came from a larger project that resulted in a 32-cm diameter LED-studded sphere, which a friend thought would make a swell necklace if it was scaled down. That larger sphere was made somewhat like a PCB soccer ball, with individual panels soldered together. [brainsmoke] didn’t relish juggling dozens of tiny PCBs to make a necklace-sized version, so the unfolded pattern for half a deltoidal hexecontahedron was laid out as one piece on single-sided FR4. The etched boards were then cut out on a CNC mill, with the joints between the panels cut as V-grooves from the rear of the board. By leaving just enough material to act as a live hinge, [brainsmoke] was able to fold the pattern up into a hemisphere while leaving the traces intact. The process was fussy and resulted in a lot of broken FR4 and traces, but with practice and the use of thicker board material and heavier copper, the hemisphere came together. The video below shows the final product
This objet d’art is [brainsmoke]’s entry in the Circuit Sculpture Contest, which is just wrapping up wrapped up last week. We can’t wait to share some of the cool things people came up with in this contest, which really seemed to get the creative juices flowing.