You know at turboboof are main focus is the transaxle Porsche (particularly the 944 and 951), but every now and then a customer comes by with a 911 and needs some help.
No problem.
Our new friend has a 996 Cabriolet with two busted "rear" window regulators... cables all chewed up... rollers worn... and more interesting... a missing plastic guide.
Now, from what I could find, Porsche does not offer this plastic guide as a replacement. They do however have a new OEM regulator for about $1000... a side!
Easy fix, but that's a hard price. Now, they didn't know that was missing when they also bought the generic, no-name, replacement cable kits. Bummer.
So I told him we'd give a shot at reverse-engineering the plastic guide and see if we could 3D-print him a "band-aid."
I heard some people say "just scan it and print it - no problem."
Stop. This part is so small, there is no way to capture the detail in a laser scan - especially with the occluded surfaces. This part needed to be precisely measured and recreated in CAD (haha, the "old-fashioned" way).
So a good few hours went into using the caliper and mic and translating that into an editable CAD file. But we did it.
Next came time to print.
The standard plastics still seem to be PLA and ABS, with PLA being the go-to for prototyping. And it worked... just fine. A few geometry issues corrected in CAD to account for PLA behavior, but we absolutely nailed it.
So what's the problem? The problem is a steel cable, at the tension the regulator holds it, would eat through the PLA guide in what I would expect, 5-10 uses (only good in a pinch). So the only answer is a stronger filament.
Checking OEM Porsche part, a small imprint is visible - "PA66". PA66 or Polyamide 66, is a high-performance engineering thermoplastic commonly known as Nylon 66 (there's even a Wikipedia page on it) is a strong, impact-resistant, and heat-resistant material widely used in the automotive industry. My guess is Porsche (or their vendor obviously) injection-molded a few thousand of these.
Where does that leave us?
Luckily there is a version of Nylon for 3D printers, IF you can get your nozzle hot enough, your bed warm enough, and your enclosed chamber heated... we can.
Because of just the perfect set of conditions we were able to replicate this part in a material suitable for it's application. Hooray for us. And good news for our customer.
And... good news for YOU (996 Porsche 911 owners) too.
Like I said, our focus is on the 944/951 - so in a show of good faith to the Porsche community, we're going to release the .stl of this part FOR FREE in the next few days. (DOWNLOAD IT HERE)
Print it however you want, but just be warned, the OEM is a very abrasion resistant Nylon 66.
And for those that don't have access to a Nylon-capable 3D-printer - you can click HERE - and buy one of ours without the infamous "Porsche-tax."
...It must be the holiday season...
E