AR | GEAR JAMMER - Bronco 7 Speed Shift Knob

[EIGHTLUG]

Just to be pedantic - It's actually the thermal effusivity that would cause the burn. Yes, conductivity is a part of that equation, but so is heat capacitance and density. When you take those into account with reasonable values the effusivity is ~14x greater for stainless steel compared to ABS. So much less than 90x.

For two semi-infinite bodies in good thermal contact; one at T_1, one at T_2 at t = 0. The temperature at the surface, T_s is a weighted average of the two surfaces effusivity.

In practical experience think grabbing a 10F steel pipe, vs a 10F piece of wood. Although both are the same temperature the pipe "feels" cooler. And as I said, yes conductivity is a portion of that equation, but doesn't tell the whole story, especially because its raised to the 1/2.

Link to material props: https://thermtest.com/thermal-resources/materials-database
Link to Effusivity: https://en.wikipedia.org/wiki/Thermal_effusivity

Can I just say, I love geek out on science posts like this.

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[Herbie]

The Organics line of shift knobs are on the road map. Leather, wood, carbon, for starters.

In the background, we're looking for local (to us) vendors that can support commercial level component manufacturing. I took Home Ec, but I can't French stitch leather to save my life. I'm also great at wood working but I'm not going to be able to turn a walnut block into a shift knob. What Andrew can design is one thing. What we can execute to the design is another. It's definitely going to happen, though.

Macrame skills?

 

[Herbie]

 

[L8apex]

Can I just say, I love geek out on science posts like this.

Have to put that MSME with a specialization in heat & mass transfer / thermodynamics to use.

Things I've heard multiple times in engineering meetings that drive me crazy:
1) Thermal mass....not a good way to describe what's happening. Thermal capacitance is.
2) Heat rises...the only direction heat cares about is going from high energy to low energy (0th law of thermo). Hot air...however does rise.

 

[EIGHTLUG]

I'll admit I'm struggling to really articulate what I'm looking for.

It isn't that I want a low quality product. I want a quality product, but I also want a product that feels like it belongs in the Bronco. I don't want a super-glossy polished luxury shift knob like the Chisel knob, because it doesn't match the overall aesthetic of the Bronco (in my opinion).

Definitely agree about the wood/leather. Some of the early interior concepts Ford released on the Bronco had leather knobs and those were fantastic looking.

I know exactly what you mean. And I can tell you, more often than not, we dial back our designs to be more 'Bronco,' if you could believe that. It's a tough line to walk. There's a design language that's unmistakable as AR without even having a logo, but it also needs to feel at home on the vehicle we're designing it for.

On the flip side of that, the Bronco isn't a cheap vehicle. It's easily on the upper end of what's available for domestic off roader. Within that, is a core of people that expect -nicer than normal- stuff. That's our comfort zone. I wish more companies played in it. Our stuff wouldn't seem so... let's say, oddly priced.

 

[HorizonHunter]

No, not necessarily. If your entire interior has been in direct sun all day, the shift knob would likely be the coolest to the touch item in the interior. If it's in the shade, but still 100+F in your interior, it will be even cooler than everything else. Read post 59. I've run 304 stainless weighted shift knobs in our race cars. It's an amazing material with a very low W/m-K. Not as low as Delin, but it's also not Delrin. It takes a considerable amount of heat to make stainless steel change temperature. Especially a chunk of it that fits in the palm of your hand.

I can confirm in a different application... Steel security enclosure for the cargo area insulates it incredibly well on a beach day. Was amazed when I opened the tailgate at how cool it was inside.

 

[Lèòn]

If I swing by the shop, will you install it?

A knob in copper would open up my wallet for sure!

Ditto, as well as Copper Pedals (3 plus dead pedal)

 

[The_Phew]

My two cents: you should focus on a leather-wrapped stainless knob first. There is a reason almost every premium vehicle with a manual transmission has a leather (or alcantara, which is played out now IMHO)-wrapped shift knob, and the aftermarket would be wise to realize that while a billet machined knob looks 'cool' in a photo, WE HAVE TO ACTUALLY TOUCH THE THING in the hot/cold.

I had the aftermarket knob below in my GTI, and it looked OEM (better than the chintzy OEM golf ball knob) and was a joy to handle. It was aluminum, and the exposed top would sear your flesh on a hot day; but you could always just handle it by the leather on the sides. Stainless would be a big improvement in the conductivity department. The interchangeable ring between the knob and the boot was a fun way to customize colors; if you did something similar, you could offer the ring in the accent colors of the various Bronco trims (Badlands orange, Black Diamond blue, etc.) And the best part of the ECS shift knob was that the ECS branding was very discrete (only on the ring, which you could face forwards so no one could see it). Just because we love your stuff (and I do), it doesn't mean I want to advertise your company in my Bronco interior. The best aftermarket parts don't scream 'aftermarket'.

 

[Lèòn]

I'm willing to change my shift knob, just give me color and leather if you're doing Stainless

I'll pay extra for options, even extra for custom powdering coating and wait for it

 

[351W-Bronco]

Veering a little off topic, but related, can I get rid of the Reverse lock-collar? I've driven manuals for decades and I've never accidentally shifted into reverse. I don't see the value in this Ford "feature".

 

[Lowcountry Bronco]

Here’s AR | WHITE BREAD

It’s your quintessential spherical cue ball, but with some added drip. Weight is right around that 1 pound mark, works with OEM Reverse Lockout, material is 304 Stainless. All of the features are post machined. It’s everything you want, and nothing that you don’t. All of the colors will be available. Retro style build, this is for you.

I like this, anyway to give color options for the numbers?

 

[NathanML]

Definitely need one of these! I’ll take the heaviest possible one you can make!

 

[stuckinohio]

These are on my radar now that I have a build date. Very interested.

 

[ricstang]

Cannot wait to see what options are available!

 

[NathanML]

Any updates?

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