Fixing a Dodge Challenger armrest

After a while traveling only with public transportation and on my singlespeed through the power of my calves, it was hightime to surrender to the fantasy obsessing me since I arrived in the U.S., and to eventually buy my dream car…

That’s right, I’m cheating on my Italian car, but while I’m in a country where fuel is half the price I’m use to, and since Dodge cars are not being distributed in France, it’s now or never.

My new Dodge Challenger, wouhouuu!

My new Dodge Challenger, wouhouuu!

But let’s not get crazy, so I looked for a used one, from 2010, since I like the design better (dat ass <3) than the new ones. To be honest I also can’t be rushed too much with features from the future such as wireless keys, as some friends already know. Well, my Challenger is well named, because it’s indeed a challenge. She really needs some love and care after being that neglected for years. People are unbelievable.

After this endless introduction, here is today’s challenge.

Of all the Dodge Challenger I’ve tested, Dodge really screwed up the armrest, because the latch holding it in place was broken every time. Ok, we’re talking American muscle, not ergonomic desk chair. But hearing a “clang” at each pothole (and there are like A LOT here), because the lid doesn’t close tight, tends to be irksome. Searching on the Internet, the replacement part seems to be around $300 with no hint if it’s compatible. So people usually reclaim springs from pegs, or hold the armrest during the whole trip. Lucky for us they only sell that car with automatic transmission so you have one hand free.

You’re starting to know me well if you’re following that blog, nothing some 3D printing can’t fix!

After tearing the armrest apart, I started prototyping. On the stock part, the spring seems to be provided by a plastic flap under the latch. It should then be easy to make a plastic replacement part. Also, there’s a screw nearby fitting in a blind hole, which will be perfect to hold the new part! Better, it should be possible to simply slide the part under the latch, clipping it and locking it in place, removing only a single screw. No need to tear the armrest apart!

After an hour or so, I’m playing with 2 possible designs. One is a little more expensive because bigger, but it can fit even if the original part has broken in an unexpected way. The other one is smaller and should behave as a stronger spring. Let’s not postpone any longer, I send these files for printing and wait for my order, rocked by the CLANG CLANG of my arm rest reassembled.

ShapewaysParcel1

And when I receive the package, without surprise, there’s a wee bit of disappointment.

First batch received

First batch received

Detail of the reverse side

Detail of the reverse side

Detail of how the big part acts as a spring on the latch, on the inside.

Detail of how the big part acts as a spring on the latch, on the inside.

Once the nearby screw is removed, simply insert the new spring part in place and clip it in the blind hole.

Once the nearby screw is removed, simply insert the new spring part in place and clip it in the blind hole.

Measurements are accurate, parts fit well but… the spring effect is a little weak. And the smaller part is in fact not resting on the latch at all, because I didn’t considered the looseness in the latch axis.

Also, it seems that the hook itself is a little worn out on my Challenger, and the smooth surface of the plastic doesn’t help the grip.

Let’s face it, a new iteration is mandatory. I readjust the design of the smaller version part, extend the spring flap a little. I also do another iteration of each version with an angle on the flap, so that the spring tension is stronger on the latch.

Without angle on the flap

Without angle on the flap

Modified part with some angle on the flap

Modified part with some angle on the flap

Finally, I also design a small shell for the hook, that will add some thickness, grip, and extend the reach.

I confirm my new order and meanwhile, I hack one of the current parts with some plastic packaging leftovers and hot glue. Clearly not ready for resale but it will bring enough peace of mind until I get the new parts.

H4ck3d

H4ck3d

H4ck3d

H4ck3d

When receiving the new batch there’s again some disappointment with some parts, but one is really good!

Because of the printing orientation, I have the perfect smoothness on the surface with the logo. It was good because I had only perpendicular faces in the previous design. Unfortunately, I didn’t think about the printing resolution, and the side with a slight angle ended up with a nice stair finish (#pixelart). Bummer, since the surface needs to be smooth so that the latch slides on it. That would mean reworking each part by hand (not what I want for other potential users) or change the printing orientation of the part, but the rest of the part will suffer from the same stair pattern. Let’s throw it away.

Those parts show a stairs pattern because of the printer resolution not smoothly reproducing the angled flap.

Those parts show a stairs pattern because of the printer resolution not smoothly reproducing the angled flap.

However, the smaller part, reworked, without the angled flap, turns out to be a perfect fit. It’s very easy to install, and the spring is just enough to have the latch moving back and forth as expected.

Final version of the latch spring.

Final version of the latch spring.

Finally, the hook shell (if you come with a better name let me know!) perfectly slides and holds firmly on the latch hook, despite my doubts concerning my measurements.

Final version of the hook shell.

Final version of the hook shell.

Shell installed.

Shell installed.

Spring installed, inside view.

Spring installed, inside view.

Spring installed, inside view, close up.

Spring installed, inside view, close up.

Just a screw to put back in place to complete the install.

Just a screw to put back in place to complete the install.

The shell simply slides on top of the hook.

The shell simply slides on top of the hook.

Install complete!

Install complete!

Now that's one nice Dodge Challenger armrest fixed!

Now that’s one nice Dodge Challenger armrest fixed!

And that’s it! I’m now driving silently, unless I floor the throttle of course, but the armrest has nothing to do with it. And as I’m sure I’m not the only one in this situation, these parts are available under OSHW licence 🙂 That’s right, you can download the STL files (files updated on July 8, 2018) and print those yourself… Or order on my Shapeways shop if you’re not sure how to do, or want to support me <3

latchSpringShapewayshookShapewaysV2.0

These parts have been designed for the Dodge Challenger SE 2010, but I’m pretty confident they are also compatible for the SXT, R/T and SRT models, and for years 2008, 2009, 2010, 2011, 2012, 2013 and 2014 as well. In doubt, contact me, we’ll check together!

Edit of July 8, 2018: I updated the STL file with the hook shell V2 which definitely improves the locking of the lid.

This entry was posted in 3D-Printing, Brimbelle Lab, DIY, Dodge Challenger, Non classé and tagged , , , , , , , , , , , , . Bookmark the permalink.

5 Responses to Fixing a Dodge Challenger armrest

  1. Eddie Elmi says:

    Thanks for this. I have to bend it so the spring action would work a little better. You think it will crack if I needs more??

    -Eddie

    • landry says:

      Hi Eddie!

      PA12 / Versatile plastic from Shapeways is quite flexible but returns to its original shape. I’m not sure about how much room you’ll have between a permanent deformation and the breaking of the part, I haven’t experimented much on that topic. Pre-heating the part in an oven at around 100 °C could give you more room but in any case there’s a risk of damaging the part. You can have a look at the material description here: https://www.shapeways.com/rrstatic/material_docs/mds-strongflex.pdf

      Before trying that, have you considered using the little hook shell I’ve mentioned in that article? Otherwise, if you want to experiment with how bending the part could improve the spring effect, you could slide a little piece of cardboard/plastic under the part to increase the angle, and see if it’s any better. That would be way safer!

      Let me know how it turns out, good luck!

  2. Larry says:

    It looks like in your photos you have cut the old spring out square, but you haven’t stated that in your blog. And you haven’t stated that in your photo descriptions. So after telling us what you have gone through and thank you for that, a step by step including removing the old plastic spring would be helpful with photos.

    • Larry says:

      Landry,
      Now I see where you say your latch on your spring was broken. My assembly is not broken yet still has the same problem of always staying open. I have photos of this that I could send you. So to mimic yours I would have to break the latch and slip your new latch in place. Rather then do that I slipped a piece of plastic between the existing latch and the spring to get rid of the play that it has which never could hold the armrest. I purchased your armrest hook to help close this for good. If the existing latch ever breaks, I have your new latch to replace the old.

      • landry says:

        Hi Larry!
        Thank you for taking the time to share your experience! Sorry if it was unclear from the post that my latch was already broken. As I got the car like that I couldn’t provide a picture of the original part that was missing.
        Glad to know that you fixed it anyway and as you said now you have the spare part in case something goes wrong (thank you for purchasing :))
        And of course, feel free to share a picture of your repair with me, if you don’t mind I’ll put it on the blog to help other people. Also it will be valuable input if I design a V2 of that part!

Leave a Reply

Your email address will not be published. Required fields are marked *