Manual transmissions! Those blessed things that car enthusiasts swear by and everyone else pretends no longer exists. They’re usually shifted by using the gearstick, mounted in the centre console of the car. Swapping out the knob on the gearstick is a popular customization; you can have everything from 8-balls to skulls, to redback spiders mounted in epoxy, sitting proud atop your gearstick. It’s rare to see anything new under the sun, but [John Allwine] came up with something we’d never seen before.
[John]’s design leans heavily on the unique ability of additive manufacturing to produce complex hollow geometries that are incredibly difficult or impossible to produce with traditional subtractive methods. The part was designed in CAD software, and originally printed on a Makerbot in plastic. After this broke, it was decided to instead produce the part in stainless steel using Shapeway’s custom order process. You can even buy one yourself. This is a much smarter choice for a part such as a gearknob which undergoes heavy use in an automotive application. The part is printed with threads, but due to the imperfect printing process, these should be chased with a proper tap to ensure good fitment.
The design was eyecatching enough to grab the attention of a professional engineer from a 3D printing company, who worked with [John] to make the part out of titanium. It’s a very tough and hardy material, though [John] notes it was an arduous task to go about tapping the threads because of this.
It’s a great example of what can now be achieved with 3D printing technology. No longer must we settle for plastic – through services like Shapeways, it’s now possible to 3D print attractive metal parts in complex designs! And, if you’ve got the right friends, you can even step it up to titanium, too.
We’ve seen other takes on the 3D shifter handle, too – like this head.
Simple machines are wonderful in their own right and serve as the cornerstones of many technological advances. This is certainly true for the humble lever and the role it plays in manual transmissions as evidenced in this week’s Retrotechtacular installment, the Chevrolet Motor Company’s 1936 film, “Spinning Levers”.
This educational gem happens to be a Jam Handy production. For you MST3K fans out there, he’s the guy behind shorts like Hired! from the episodes Bride of the Monster and the inimitable Manos: The Hands of Fate. Hilarity aside, “Spinning Levers” is a remarkably educational nine-ish minutes of slickly produced film that explains, well, how a manual transmission works. More specifically, it explains the 3-speed-plus-reverse transmissions of the early automobile era.
It begins with a nod to Archimedes’ assertion that a lever can move the world, explaining that the longer the lever, the better the magic. In a slightly different configuration, a lever can become a crank or even a double crank. Continuous motion of a lever or series of levers affords the most power for the least work, and this is illustrated with some top-drawer stop motion animation of two meshing paddle wheels.
Next, we are shown how engine power is transferred to the rear wheels: it travels from a gear on the engine shaft to a gear on the drive shaft through gears on the countershaft. At low speeds, we let the smallest gear on the countershaft turn the largest gear on the drive shaft. When the engine is turning 90 RPM, the rear wheel turns at 30 RPM. At high speeds using high gears, the power goes directly from the engine shaft to the drive shaft and the RPM on both is equal. The film goes on to explain how the gearbox handles reverse, and the vast improvements to transmission life made possible through synchromesh gearing.
Continue reading “Retrotechtacular: We’re Gonna Have Manual Transmissions The Way My Old Man Told Me!”
If that stick shift just doesn’t feel right in your hand it’s time for a change. This hack puts a gaming joystick in the center console of your hoopty as a gear shifter.
[Ilias] used a joystick from about 1991 to replace the stock shifter. It jogs our memory when he mentions that this thing saw a lot of use playing X-wing vs. Tie Fighter. Boy did we burn up a ton of time playing that one too! He actually broke the stock part getting it off (find a shop manual for your car if you’re afraid of this). But once the grip was removed he was relieved to find the joystick fit perfectly. The two molded plastic halves of the joystick screw together. To join them with the shifting level he used epoxy putty.
The momentary push switch for that thumb button is still in there. But it doesn’t look like he hooked it up to anything. If we were to give this one a try we’d have to find some use for it. Got any suggestions? Let us know in the comments.
[Ben] bought a remote starter for his car but needed a way to make sure the manual transmission was in neutral when starting. He built this infrared sensor frame to detect the position of the stick. It uses four beam paths which will tell him the exact gear or neutral position of the shifter. For this project he just needs to detect neutral but exact gearing is apparently necessary information for his next hacking project. We initially were worried about sunlight interfering with the sensor readings but he’s building this to go under the collar that is used to cover up the mechanical joint at the base of the stick.