Works-Like Machines in Progress!

Intro

Hi, everyone! Cooper here. Coming into March we have started on a works-like version of the Betta Wire. This past week we wrapped up a sprint that aimed to leave us with a usable upper tool and lower tool as well as collected lifetime data on some of our components in the EDM environment.

We are making progress on the Powercore V3 and are hoping to get some early units out to a select few of the V2 customers.

Betta Wire

Tools

Our works-like tools are key to getting data on our newest Betta Wire revision and now they're functional! 

All functional features are present on the new upper toolhead, including a new, and rather more complex, energizer spring.

This spring was designed to replace several components and multiple PCBs from the previous design. This new energizer spring will serve to join both the wire and the hole popper electrodes into the circuit.

By pre-loading the wire against the idler that is read by the magnetic encoder, we will be able to collect and utilize information directly from the wire's motion. This will allow us to check for errors in feeding and to actively and precisely control wire draw speed, leading to more ideal cuts in more materials.

This was a really interesting and new part to design. I had a TON of fun designing and fabricating this spring. 

Works-Like Machine Build

Something we had to do was determine whether we should even begin a works-like machine in the first place. Obviously we should, but would the components we had selected be able to survive the rigors of motion in a dirty, underwater environment? We had to test this. 

Specifically, we were curious to see how well the 304 stainless LM10UU bearings worked under dirty water. We had previously conducted corrosion tests on these bearings that resulted in functional bearings after 4 months submerged in dirty water.

This time around, we needed to test lifetime of these bearings in an underwater, abrasive environment in motion. To do this, we constructed a basic test rig:

Luckily for us, WEDM motion is very slow, so by speeding up the motion of the above test rig, we were able to get a significant amount of data in a relatively short period of time. 

The bearings were coated with Corrosion X rust preventative and placed on the test rig. The rig was then placed in a small fish tank that contained EDM waste from machining steel with a brass electrode.

We also grabbed the first handy container to store the waste water:

Test notes from John's records:

 "...test operates at 31.25 mm/second with 156.25 mm/second² acceleration/deceleration, completing 25,000 cycles (3 km total travel) over approximately 29.5 hours..."

This test represents what we estimate to be over a year of cutting in an actual EDM environment at higher, i.e. likely more destructive, speeds. Our test results showed impressive resilience in these bearings.

Even if bearings need to be serviced once or twice a year with frequent use, this shows that these parts will function well. We have already purchased many of the remaining parts for several units of the works-like build, including these bearings.

Machine Control

Because of our move to Linux CNC, we required a more specialized control board. The current boards on the market either lacked features, or were unable to convince the team of their reliability. 

As of today, our new version of our control board has been assembled and is currently being tested!

With this board, we will be able to use a Raspberry Pi (or similar) to directly control our 4-axis WEDM system. We will be able to communicate to and from the Powercore V3 and use the adaptive feed control features in Linux CNC. We are very excited for this control board!

Powercore V3

Progress on the Powercore V3 is going well! We are currently awaiting our Rev D of the new motherboard.

As we await this board, we are moving towards machining the works-like enclosure. There are advantages and disadvantages to machining the enclosure locally. One such feature that happens to be both is the need for tooling! We have recently acquired Pierson quick change pallets, something that will significantly help iteration and production speed. They just happen to be a bit pricey.

By moving to an integrated enclosure and heat sink, we will be able to remove the fan, another point of potential failure, from the Powercore V3.

We are looking to eventually cast these units, but that will require a bit more scale to justify a die cast run.

Overall, things are going smoothly on the Powercore V3. About as well as expected. We'll update more thoroughly on the Powercore V3 once we are able to start putting it through its paces. When we are able to validate the newest version, we will begin to put the source for those on our Github.

Wire Tool Kits

Wire Tool Kits, while important, have not been the subject of any recent work. This is intentional. As we finalize changes to the Betta Wire toolheads, we are learning what works best for drawing and energizing wire.

Those improvements will be brought over to the Wire Tool Kit V2. These changes include new and improved wire guides (set of 2 for better control) and superior wire speed controls.

The Wire Tool Kit is a much more open-ended solution for WEDM. As such, we will not be able to give guidance on every single machine or implementation. This said, we are working hard to ensure that every part of the equation that we do have control over works in your favor.

Closing Thoughts

It doesn't look like we're going to be able to begin deliveries of most of the units before the end of Q1 this year. We hope to be able to get some of the very first, pre-release Powercore V3s out shortly. Those of you who will receive these know who you are! The remainder of the pre-orders are likely to ship in Q2. As we get closer to a completely functional, representative machine tool, expect a lot more media from us!

We will not be sending out pre-release or specially QC'd units to reviewers or influencers. That never seems to end well and we want to stand behind all of the products that we send out. That's a big reason why we release our products opensource. Even if we're gone, you're not left behind.

On the bright side, it looks like once we're in production with the new Powercore V3, we'll be able to stay in production. We have a lot more control over this EDM PSU and have been reducing complexity wherever possible. 

As we move on through works-like and into works-like/looks-like Betta Wire and Powercore V3, the Canuck Creator reminded us of a quote attributed to Shigeru Miyamoto on one of his recent livestreams:

"A delayed game is eventually good, but a rushed game is forever bad."

Remembering these words, I am incredibly excited to bring something amazing to you all. Looking forward to sharing more next month!

-Cooper