Repairs You Can Print: A Turn Signal Switch For A Chevy Corvair

Running a classic car is often an easier prospect than a more recent model, as the mechanical parts have a tendency towards commonality between models, simplicity, and maintenance using basic tools. However assuming some level of parts availability for your model it is not usually the running gear that causes headaches. Instead, it is the smaller and less durable parts, the little plastic pieces that formed vital components but have not been manufactured for decades. These are the parts for which the advent of accessible 3D printing has been a revelation, suddenly the owner of a wreck need only to have basic CAD skills to deliver the goods.

A Chevy Corvair (not [Ken]'s one). Greg Gjerdingen [CC BY 2.0].
A Chevy Corvair like [Ken’s]. Greg Gjerdingen [CC BY 2.0].
[Ken] has a ’63 Chevy Corvair, an attractively-styled motor notable for its rear-engined layout and air-cooled engine. And it seems his car is plagued by the same issue as all other early models, a failure of its turn signal mechanism. The version fitted to later cars is a vastly superior replacement, but required some modification to fit his ’63 model. Even after modifcation, the updated part had a plastic component that was too long for his steering wheel. Would he grind down the later part to fit, or go with a later wheel? No, he turned to Google Sketchup, and 3D printed a replacement of the correct size. He does admit that it’s not perfect as the signals cancel at a slightly different point from where they should, but since he’s been using it for four years it appears to have done the job.

We wish [Ken] every success with his Corvair, and indeed can’t help envying him a little for owning it. Some of us have been known to dabble in older metal, too.


This is an entry in Hackaday’s

Repairs You Can Print contest

The twenty best projects will receive $100 in Tindie credit, and for the best projects by a Student or Organization, we’ve got two brand-new Prusa i3 MK3 printers. With a printer like that, you’ll be breaking stuff around the house just to have an excuse to make replacement parts.

 

Repairs You Can Print: A Little Love For The Glove Box

A few years ago, [Brieuc]’s car blew a fuse. He went to replace it, which unfortunately means removing the entire glove box. In his haste to get his baby back on the road, he accidentally broke one of the clips that holds the glove box on the dashboard.

[Brieuc] tried to just glue the thing back together, but it didn’t hold because the part has to flex a little bit for people who need to get into the fuse box. No one seems to offer a replacement for this small but vital hunk of plastic, though he did find someone offering total glove box replacements at highway robbery prices. Since there was still one good clip, he used it to design and print a strong ABS replacement.

This is a great example of the one-off utility of 3D printers. [Brieuc] didn’t need an exact copy, and since he was replacing an injection-molded part with additive manufacturing, he had the freedom to start with a bare-bones design, make adjustments as needed, and iterate until he got it right. It didn’t take long. The layer orientation of the first print made the legs too weak, but that’s a simple fix. The second version has lasted for three years and counting.

We get it. You don’t have the same car as [Brieuc], so this particular fix doesn’t sway you. But someday in the future when your zipper breaks or your dishwasher detergent cup won’t latch, 3D printing will be there to help.

Boost Tube Replacement Through 3D Printing

[Sam] is the lucky owner of a 1990 VW Corrado G60. To the uninitiated, that’s the souped-up, go fast version with the fancy supercharger on top. While performing some mods to the air intake (car-speak for “hacks”), there came a need for a custom tube to eliminate the original silencer box. With available options costing up to $400, suddenly 3D printing a replacement seemed like a better answer.

3D printing intake parts for a supercharged vehicle has some unique challenges. The intake must be able to take the boost pressures seen by the engine, in this case up to around 10 psi. There must be no air leaks at all as this risks confusing the sensors that measure how much air is entering the engine. Lastly, the tube must be able to withstand the hot, and often oily environment under the hood.

The first attempt was completed with TPU filament, which unfortunately did not hold pressure. A followup with PLA fared better, but was unable to withstand the heat present in the engine bay. After some experimentation, a successful print was made in PETG which was more robust. In the final design, [Sam] applied a rubber coating and then some aluminum tape, to both help seal any micro-holes in the 3D printed surface as well as help protect against heat.

After over a month of testing, [Sam]’s data logs indicate the tube is performing well and holding boost. It goes to show that with some perseverance and iterative design, 3D printed parts can often save the day.

Perhaps you’re inspired by this hack but need to jack up your car to work on it? Never fear, you can 3D print those too.

Slimline Proximity Fob Makes Life Easier

Modern cars these days tend to come with proximity keys, which allow the driver to unlock and start the vehicle without having to remove the key from one’s pocket. While this is a great usability upgrade, for some reason key fobs continue to be bulky plastic monstrosities that when stuffed into a pocket can easily ruin the lines of a well-chosen outfit. This wasn’t good enough so [Patrick] decided to sort it out.

Starting with a Prius key, the first step was to disassemble the already broken key fob and separate out the PCB from the case and battery holder. With those removed, a coin cell was soldered to some wires connected to the PCB. As a substitute for the original case, a plastic card was cut up and the PCB inserted within, allowing the setup to fit neatly in a wallet’s card pocket. Lashings of tape bring the project home.

Unsurprisingly, it works, and works well. It raises the question why key fobs are so large and ungainly, taking up so much precious pocket space. We’d love to see even slimmer takes on this with 3D printed enclosures or even completely redesigned PCBs. Give it a go, and hit up the tip line. Else, check out how key fobs are routinely hacked to steal cars.

Road Apology/Gratitude Emitter Car LED Sign

Sometimes, when you’re driving, a simple wave when someone lets you in can go unnoticed and sometimes you make a mistake and a simple wave just isn’t enough. [Noapparentfunction] came up with a nice project to say ‘Thanks’ and ‘My Bad’ to his fellow drivers.

The display uses four Max 7219 LED matrix displays, so the total resolution is 32 by 8. [Noapparentfunction] came up with an inspired idea: using a glasses case to hold the LED matrices and Raspberry Pi. It’s easy to get into if necessary, stays closed, and provides a nice finished look. Having little knowledge of electronics and no programming skills, [Noapparentfunction] had to rely on cutting and pasting Python code as well as connecting a mess of wires together, but the end result works, and that’s what matters.

A network cable runs from the glasses case suction cupped to the rear window to another project box under the dashboard. There, the network cable is connected to two buttons and the power. No network information is passed, the cable is just a convenient collection of wires with which to send signals. Each of the buttons shows a different message on the display.

Depending on where you live, this might not be legal, and we’re sure many of our readers (as well as your author) could come up with some different messages to display. However, this is a cool idea and despite [Noapparentfunction]’s admitted limitations, is a nice looking finished product. Also, its name is Road Apology Gratitude Emitter. Here are some other car mod articles: This one adds some lighting to the foot well and glove compartment and this one on the heinousness of aftermarket car alarms.

Wrecked Civic Rides Again As Cozy Camp Trailer

It may not be the typical fare that we like to feature, but you can’t say this one isn’t a hack. It’s a camp trailer fashioned from the back half of a wrecked Honda Civic, and it’s a pretty unique project.

We don’t know about other parts of the world, but a common “rural American engineering” project is to turn the bed and rear axle of an old pickup truck into a trailer. [monickingbird]’s hacked Civic is similar to these builds, but with much more refinement. Taking advantage of the intact and already appointed passenger compartment of a 1997 Civic that had a really bad day, [monickingbird] started by lopping off as much of the front end as possible. Front fenders, the engine, transmission, and the remains of the front suspension and axle all fell victim to grinder, drill, and air chisel. Once everything in front of the firewall was amputated, the problem of making the trailer safely towable was tackled. Unlike the aforementioned pickup trailers, the Civic lacks a separate frame, so [monickingbird] had to devise a way to persuade the original unibody frame members to accept his custom trailer tongue assembly. Once roadworthy, the aesthetics were tackled — replacing the original interior with a sleeping area, installing electrics and sound, and a nice paint job. Other drivers may think the towing vehicle is being seriously tailgated, but it seems like a comfy and classy way to camp.

Now that the trailer is on the road, what to do with all those spare Civic parts? Sure, there’s eBay, but how about a nice PC case featuring a dashboard gauge cluster?

They’re Putting Soy In Your Wires, Man

I’ve got a friend who tells me at every opportunity that soy is the downfall of humanity. Whatever ails us as a society, it’s the soy beans that did it. They increase violent tendencies, they make us fat and lazy, they run farmers out of business, and so on. He laments at how hard it is to find food that doesn’t include soy in some capacity, and for a while was resigned to eating nothing but chicken hot dogs and bags of frozen peas; anything else had unacceptable levels of the “Devil’s Bean”. Overall he’s a really great guy, kind of person who could fix anything with a roll of duct tape and a trip to the scrap pile, but you might think twice if he invites you over for dinner.

A column of soy soldiers stand at the ready.

So when he recently told me about all the trouble people are having with soy-based electrical wiring, I thought it was just the latest conspiracy theory to join his usual stories. I told him it didn’t make any sense, there’s no way somebody managed to develop a reliable soy-derived conductor. “No, no,” he says, “not the conductor. They are making the insulation out of soy, and animals are chewing through it.”

Now that’s a bit different. I was already well aware of the growing popularity of bioplastics: the PLA used in desktop 3D printers is one such example, generally derived from corn. It certainly wasn’t unreasonable to think somebody had tried to make “green” electrical wiring by using a bioplastic insulation. While I wasn’t about to sit down to a hot bag of peas for dinner, I had to admit that maybe in this case his claims deserved a look.

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