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Cable Knobs for Heat, Alt Air and Oil Cooler Shutter?

claycookiemonster

claycookiemonster

Well Known Member
I'm getting around to installing these cables and using them as practice for the Throttle, Mixture and Prop cables still to go.

As I looked at the cable and knob, I couldn't help wondering if the shape of the knob might be altered to I can tell which one I'm grabbing without looking. The knob itself seems to have been pressed onto the cable without any consideration for removing it.

Has anyone attempted to alter the knobs for these three functions? Anyway to remove the knob short of destroying it? Might there be some international standard for knob shape for these operations? (Probably kidding about that)
 
Knobs.....

claycookiemonster said:
I'm getting around to installing these cables and using them as practice for the Throttle, Mixture and Prop cables still to go.

As I looked at the cable and knob, I couldn't help wondering if the shape of the knob might be altered to I can tell which one I'm grabbing without looking. The knob itself seems to have been pressed onto the cable without any consideration for removing it.

Has anyone attempted to alter the knobs for these three functions? Anyway to remove the knob short of destroying it? Might there be some international standard for knob shape for these operations? (Probably kidding about that)
Click to expand...

I think where the placement is in the cockpit (in an RV-4, anyway) is more important than the shape of the knob itself. My carb heat is a "T" handle in line with the throttle so a go-around full throttle places my hand on that "T" handle. The oil cooler door is just outboard of that. Heat and cold air are on the right side and are different shapes because that is what I had at the time. My alternate air is a switch under a blue safety cover on the right upper panel. Pretty easy to get to that. Throttle mixture are on the left side wall in the standard placement. Both are round knobs but the throttle is higher and longer than the mixture. Throttle is black; mixture red. Trim is a blue knob WAY above the throttle/mixture. I've never confused any of those as they seem like "standard placement".

For panel-mounted knobs, it might be a different issue.
 
Labels

I can share an Adobe Illustrator file with labels.
Shoot me an e-mail.
I can also share the contact info of the friend who printed them. One strip wide was $20 plus shipping. I got five or six sets of labels.
I was giving them away but I'm down to my last two sets.
Sorry about the bad word on the middle label. It was meant as a joke to use up the open space
20221226_103738.jpg
 
Okay, so apparently, there is no "standard" knob shape for the functions I'm talking about. I expect that over time I'll get just fine at knowing which is which by feel, and labeling will be superfluous. But, what if I want to use or fab different knobs for those functions?
Has anyone tried and succeeded in removing the standard knobs and replacing them with knobs of their own creation?

DAR's and wise folks out there: any issues with replacing the standard knobs, or perhaps adding an outer layer of something to create a different shape?

This is a bit of a lark, but if I didn't enjoy going off the reservation, I'd probably own a Cessna. A fine, old, reliable, standard shaped knob if there ever was one.
 
For reference, there are different shapes available. Take a look at 70's vintage certified airplanes and you'll find round knobs, square knobs and T-shaped handles. There's no reason you can't come up with your own. Even the standard round black knob could, with some judicious filing, become hexagonal, for example.

A different tactile response is a very good thing to have to aid in differentiating controls in the cockpit. Also consider adding a ratcheting cable to the mix in addition to knob shape as a tactile differentiator. That way you might get two knobs that feel the same but one moves smoothly and the other has the tell-tale ratchet feel to it.
 
claycookiemonster said:
Has anyone tried and succeeded in removing the standard knobs and replacing them with knobs of their own creation?
Click to expand...

Might help to know what kind of cable/control/knob you're talking about. E.g., it'd be relatively easy with a DJM quadrant, but probably much more difficult with something like a McFarlane Universal Push-to-Unlock, or a Vernier control, etc.

More specific info might help here.
 
claycookiemonster said:
One of these:

https://store.vansaircraft.com/72-push-pull-cable-black-knob-ct-a-740-black.html

The standard Bowden cable with a round knob on one end. I've looked at this and can't find a way to remove the knob and replace it with another one of a different shape.

Finding or creating a different knob seems to be the easy part, removing the one already there looks to be the challenge.
Click to expand...

Yeah, that knob is probably epoxied on, or perhaps molded onto it, and likely not coming off. Sounds like you'll need to purchase a different cable if you want to proceed. Spruce has some, McFarlane has a bunch of options.
 
Push button knob

Clay,
Do consider using center-button knobs for your oil shutter and footheat knobs. I want mine to stay precisely where I set them, no movin’ around.
 
Ok, I tried just now to screw off the knob on the Bowden cable. I had pliers on the inner shaft as hard as I was willing to squeeze and the knob did not budge. As to center push-button actuating cables that presumable remain locked in place unless the aforementioned button is pushed, interesting idea. I get it. Where did you get them?
 
claycookiemonster said:
Ok, I tried just now to screw off the knob on the Bowden cable. I had pliers on the inner shaft as hard as I was willing to squeeze and the knob did not budge. As to center push-button actuating cables that presumable remain locked in place unless the aforementioned button is pushed, interesting idea. I get it. Where did you get them?
Click to expand...

I used one of these but I don't recall them so expensive. I used it for the parking brake.
The others (alt air, heat & oil temp) are wratchet type. It takes some effort to move them. Both have gone up in price!
If you look at the AI file I sent, the "Parking Brake" label is doughnut shaped to allow for the center release button.
 
claycookiemonster said:
Ok, I tried just now to screw off the knob on the Bowden cable. I had pliers on the inner shaft as hard as I was willing to squeeze and the knob did not budge. As to center push-button actuating cables that presumable remain locked in place unless the aforementioned button is pushed, interesting idea. I get it. Where did you get them?
Click to expand...

My experience with Vans cables too - - MacFarlane make some good cables, and knobs screw on. If you get the center locking button, be extremely careful not to pull out the plunger and drop the tiny ball bearings. I was inspecting the cable, know better, but still managed to release one of the little buggers. MacFarlane can provide replacements. I noted they are a little larger in diameter cables than Vans, so have to note the firewall penetration and other things like mounting nut size. I can not recall where, but knobs with engraving are available too.
 
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