repair

265 Articles

Impulse Buying A 3040 CNC Machine, What Could Go Wrong?

August 26, 2023 by 46 Comments

[joekutz] made an impulse purchase of a CNC machine. It was a 3040 CNC that looked reasonably complete and had an attractive price, what could possibly go wrong? As it happens, [joekutz] really didn’t know what he was in for. Sometimes the price is good, but you pay in other ways. But where some would see defeat, [joekutz] sees an opportunity to document the restoration.

Dial indicators are useful tools for measuring how straight some parts aren’t.

The 3040 are relatively cheap and simple CNC machines that have been available from a variety of overseas retailers for years. They have 30 cm by 40 cm beds (hence the name) and while there are many variations, they all work about the same. [joekutz] expected that getting his up and running and converted to open source would be a fun weekend project, but it ended up taking far longer than that. In fact, it turns out that the machine was damaged in surprising and unexpected ways.

[joekutz] has a series of videos demonstrating the process of diagnosing and repairing the various things wrong with this device. In the first video, he dismantles the machine and discusses the next steps. In the second video, he takes some time to repair some dial indicators that will be critical for measuring the various things wrong with the CNC parts. Video number three delves into finding out the horrible things wrong with the machine, and the fourth is where repairs begin, including bending shafts and sanding blocks back into service.

Those videos are embedded below, and while the machine isn’t quite restored yet, progress is promising. We’ve seen easy and effective upgrades for such CNC machines before, but if you happen to be in more of a repair and restore situation, give [joekutz]’s work a look because it might just save you some time and frustration.

Continue reading “Impulse Buying A 3040 CNC Machine, What Could Go Wrong?” →

Repairing A Home Injection Molding Machine

August 5, 2023 by 10 Comments

When [Michael] over at the Teaching Tech YouTube channel bought a hobby injection molding machine a long time ago, one of the plans he had with it was to use it for grinding up waste bits of PLA filament for injection molding. Since the machine was bought from a US shop and [Michael] is based in Australia it required some modifications to adapt it to the local 220+ VAC mains, followed by adding a PID temperature controller and a small compressor to provide the compressed air rather than from a large shop compressor.

Although [Michael] had discussed using the machine for PLA with the seller to confirm that this would work, a user error meant that the now defective unit had been sitting idly for many years, until recently.

Since the machine had been gathering dust and rust in the garage, fixing the machine up took a complete teardown to remove corrosion and resolve other issues. After this the original fault was identified, which turned out to be a shorted wire near the heater which had been turned up to a too high temperature, leading to the release of magic smoke and banishment of the machine to the Pit of Despair, AKA the shadowy depths of one’s garage.

In this first installment, [Michael] cleaned up the machine and restored it to a working state. In the next part injection molding will be attempted again, which should give some idea of the feasibility of turning scraps of PLA and failed 3D prints into smooth injection molded parts, assuming you have the CNC machine or patience to carve out the requisite molds, of course.

Continue reading “Repairing A Home Injection Molding Machine” →

An exploded view of an AirPods Pro case. The outer case consists of two long, capsule-shaped sections that enclose several smaller parts including the wireless charging cable, contacts for charging the AirPods themselves, and the top rounded protective piece for the buds that nestles into the top capsule. This version includes screws to fasten everything together instead of adhesives.

Fixing Some More Of Apple’s Design Mistakes

August 2, 2023 by 26 Comments

Love them or hate them, there’s no denying that Apple has strayed from the Woz’s original open platform ideal for the Apple II. [Ken Pillonel] is back for another round of fixing Apple’s repairability mistakes with a full complement of 3D printable replacement parts for the AirPods Pro case.

While modeling all of the parts would be handy enough for repairing a device with a 0/10 iFixit score, [Pillonel] modified the parts to go together with screws instead of adhesive so any future repairs don’t require cracking the plastic egg. He says, “By showcasing the potential for repairability, I hope to inspire both consumers and multi-billion dollar companies, like Apple, to embrace sustainable practices in their products.”

[Pillonel]’s repairability exploits may seem familiar to readers from his previous work on adding USB-C to the iPhone and the AirPods Pro case. If you just need to retrieve a lost AirPod, you might try an electromagnet, or you can make a Bluetooth receiver from a pair of knock-off buds.

Continue reading “Fixing Some More Of Apple’s Design Mistakes” →

Nail, Meet KiCad

July 24, 2023 by 25 Comments

You know the old saying. When all you have open is KiCad, everything looks like a PCB. That was certainly true for [Evan], who needed to replace a small part recently and turned to PCBs to get the job done.

The part in question was a sheered apart detent cam from a retractable cord reel. Glue and epoxy might have worked, and [Evan] was worried about how a 3D printed PLA part would have held up. The part is an extruded 2D shape, making PCBs a non-traditional but viable choice. Using the old scanner trick, he traced the outline in KiCad 7 (which adds image references). Then with the five boards stacked up, solid core wire, solder, and a propane torch worth of heat fused it. Ultimately, this machine’s tolerances are generous, so it worked wonderfully.

Was it the “right” tool for the job? Right or wrong, it is hard to argue that in terms of durability and ease per dollar, this doesn’t come out on top. PCB files are on GitHub if you have a 5020TF-4c retractable cord reel that needs a new cam. PCBs have a fun way of adopting different use cases like enclosures, but perhaps the idea of PCBs as a mechanical part could be applied elsewhere.

Do Not Attempt Disassembly: Analog Wizardry In A 1960s Counter

June 12, 2023 by 22 Comments

[CuriousMarc] is back with more vintage HP hardware repair. This time it’s the HP 5245L, a digital nixie-display frequency counter from 1963. This unit is old enough to be entirely made of discrete components, but has a real trick up its sleeve, with add-on components pushing the frequency range all the way up to 18 GHz. But this poor machine was in rough shape. There were previous repair attempts, some of which had to be re-fixed with proper components. When it hit [Marc]’s shop, the oscillator was working, as well as the frequency divider, but the device wasn’t counting, and the reference frequencies weren’t testing good at the front of the machine. There were some of the usual suspects, like blown transistors. But things got really interesting when one of the boards had a couple of tarnished transistors, and a handful of nice shiny new ones — but maybe not all the right transistors. Continue reading “Do Not Attempt Disassembly: Analog Wizardry In A 1960s Counter” →

Plastic Welding Revisited

June 7, 2023 by 27 Comments

Last time we talked about a video that purported to do plastic welding, we mentioned that the process wasn’t really plastic welding as we understood it. Judging by the comments, many people agreed, but it was still an interesting technique. Now [Inventor 101] has a video about plastic repair that also talks about welding, although — again, we aren’t sure all of the techniques qualify.

That’s not to say there aren’t some clever ideas, though. There are several variations on a theme, but the basic idea is to use a bolt or something similar in a soldering iron, metal reinforcement from things like wires and staples, and donor plastic from a zip tie. While we don’t think the nylon in a typical zip tie is the best way to repair anything other than nylon, if you were repairing something 3D printed, you could easily swap out the tie for filament of the same material, which — we think — would bond better.

Continue reading “Plastic Welding Revisited” →