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McFarlane vernier-assist throttle cable 14A

romaja

Well Known Member
I would like to install a McFarlane vernier-assist throttle cable on my RV-14A IO-390 EXP and was wondering if anyone knows the exact model number.

Thanks,
Jim
 
I would like to install a McFarlane vernier-assist throttle cable on my RV-14A IO-390 EXP and was wondering if anyone knows the exact model number.

Thanks,
Jim

Not mine but someone I know who did this with his throttle showed me this package so I took the picture.
 

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Not mine but someone I know who did this with his throttle showed me this package so I took the picture.

Oops. That’s not my throttle cable. McFarlane doesn’t have the vernier assist as a stock item for the -14. They will custom make one for you.
 
Thanks for the replies!

If/when you do get exact part numbers, will you please post them here or send a PM to me? I’m also planning on using the McFarlane vernier-assist throttle and prop cables as part of my -14 build.
 
Vernier throttle

If acro or formation are in your plans, don’t use a vernier throttle. My strong opinion based on using them. Yes if only a cross country machine
 
If acro or formation are in your plans, don’t use a vernier throttle. My strong opinion based on using them. Yes if only a cross country machine

These are vernier-“assist”….totally different from standard vernier. They’re really nice cables and give you the best of both worlds…..easy push/pull along with the fine tuning of a twistable knob.
 
These are vernier-“assist”….totally different from standard vernier. They’re really nice cables and give you the best of both worlds…..easy push/pull along with the fine tuning of a twistable knob.

Thanks for clarifying. Their seems to be some confusion concerning the vernier-“assist”
and the standard vernier knob that has been around for years.

From McFarlands website:

Vernier and Friction Lock - The Best of Both

You asked for it and now we have it. Not only do we offer Vernier-Assist for non-certified aircraft and an extended line of FAA-PMA approved controls, the breakthrough design is now approved on throttle controls for Cessna, Piper, Beechcraft, Grumman, and Bellanca.

Now FAA-PMA Approved!
Jam-proof safety
Precision power adjustments
Smooth friction control
Light and compact
Standard Vernier performance without the button!

McFarlane’s patented Vernier-Assist™ offers the pilot precision control of the engine, unlike anything else on the market! The Vernier-Assist assembly operates on friction alone by simply turning the knob, with no threads or locking balls/pins. It also allows for normal coarse movement by pushing in or out on the knob. Unlike standard threaded vernier controls, this design cannot be jammed. The friction control provides smoothness and precision when operating the throttle and a friction lock secures the control in position, but it can be easily overridden in the case of an emergency. It is SAFE!

These light weight controls use a patented roller action and do not use a positive lock thread engagement. Coarse adjustments are made by pushing the knob inwards or pulling the knob outwards. Fine adjustments are made by rotating the knob clockwise or counterclockwise. For extreme conduit routing or heavy carburetor load installation, slight inward or outward assist pressure could be required during rotation.
US Patent No. 8,485,057 B1
 
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If acro or formation are in your plans, don’t use a vernier throttle. My strong opinion based on using them. Yes if only a cross country machine

The McFarlane Vernier Assist throttle is an OUTSTANDING throttle for formation flight. Like others already said, it is not your typical push-button vernier throttle (which should NEVER be use for formation flight). This is a normal push-pull throttle, but with the benefit of fine-tuned power changes by turning the knob.

As a flight lead, I love the vernier assist. If a wingman calls "Lead give me one," I give the throttle knob a full twist to the left, which in my setup reduces manifold pressure by 1 inch. For 4-ship echelon turns, I'll twist out one inch entering the turn for the sake of #4, then twist that inch back in upon roll-out.

It's a very smooth throttle, even with engine area temperatures up in normal operating range.

As for the "stock" throttle, don't bet on finding one. I had to order mine special using their order form's measurement guides.
 
When I ordered mine, I really wished that I could’ve found a sample of the measurements that someone else had taken, but could not. I’m attaching my order form so you have somewhat of a reference while taking your own measurements, and you should absolutely take your own measurements. Although the throttle cable is installed, I have not yet started up the engine, so I can’t confirm that I nailed everything perfectly. One thing to note is that the gimbal grommet that vans provides for the firewall pass-through has smaller diameter openings in it than the diameter of the MacFarlane throttle cable. I put a round file in a drill and reamed out the hole of the gimbal grommet to fit. The gimbal grommet is steel, so it took a while. I’ve flown an RV 12 with the vernier assist throttle, and it’s worth every penny.
 

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I would like to install a McFarlane vernier-assist throttle cable on my RV-14A IO-390 EXP and was wondering if anyone knows the exact model number.

Thanks,
Jim

If these assist cables costs hundreds of dollars apiece (probably $500 plus) and I was still in the convenient building stage, I’d be looking hard instead at a center mounted throttle quadrant if formation flying was my thing…
 
If these assist cables costs hundreds of dollars apiece (probably $500 plus) and I was still in the convenient building stage, I’d be looking hard instead at a center mounted throttle quadrant if formation flying was my thing…

See post #9.

Regarding the measurement, use some tygon tubing or even R/C fuel tubing and determine the length. Also, McFarlane's tech line is extremely helpful in helping answer questions.

In my case, I put another hole in the firewall to avoid running the control cables with signal/electronic lines as suggested on this forum. So, there is no "standard length" in my case. Also, I used an FM-150 fuel servo which changes the geometry a bit.

McFarlane will custom make the lengths in just a day or so and get them out to you very quickly.

No, I don't work for McFarlane, but they are almost in my back yard so I know many folks that work there and use them whenever possible. Super high quality stuff, great service, and most of all...they act like they want my business.

Hope that helps!
 
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When I ordered mine, I really wished that I could’ve found a sample of the measurements that someone else had taken, but could not. I’m attaching my order form so you have somewhat of a reference while taking your own measurements, and you should absolutely take your own measurements. Although the throttle cable is installed, I have not yet started up the engine, so I can’t confirm that I nailed everything perfectly. One thing to note is that the gimbal grommet that vans provides for the firewall pass-through has smaller diameter openings in it than the diameter of the MacFarlane throttle cable. I put a round file in a drill and reamed out the hole of the gimbal grommet to fit. The gimbal grommet is steel, so it took a while. I’ve flown an RV 12 with the vernier assist throttle, and it’s worth every penny.

Thanks!
Very helpful. I will also take my own measurements.
 
Hey I remembered how I computed my custom measurements for the McFarlane throttle's custom build. Since Van's offers a standard size throttle assembly for my YIO-360 M1B, I ordered a throttle from Van's for the sole purpose of taking the measurements. Once I took those measurements and wrote them onto the McFarlane order form, I repackaged the new/unused throttle assembly and returned it to Van's. This cost 2 or 3 dozen dollars in restocking fee, but I now had precise numbers. A few weeks later, I received a perfectly-measured McFarlane vernier-assist throttle cable.

If your engine comes with a throttle cable (or one is available), it may be worth your time and money to do what I did.
 
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Thanks!
Very helpful. I will also take my own measurements.

Regarding the firewall eyeball fitting. I had the same concerns and so I emailed McFarlane. Here is the response I received from the custom cable department.

The Bulkhead fitting is .440"

The conduit diameter is .305"

Hope this help.

Thanks,

I reamed the eyeball fitting to .3”, both holes. I haven’t yet ordered my throttle cable but I plan on using a length of COAX to route and measure.
 
If these assist cables costs hundreds of dollars apiece (probably $500 plus) and I was still in the convenient building stage, I’d be looking hard instead at a center mounted throttle quadrant if formation flying was my thing…

I never mentioned formation flying in my post. That said, If was interested in this type of flying, I would be happy with the micro adjustments the vernier assist cables provide as others in the post have eluded to.

FYI, the center consoles at Aerosport are approximately $1300.00 in addition to the special length cables that will be required.

I am curious as to why you feel center mounted throttle quadrants are good or possibly better for formation flying?

Jim
 
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The McFarlane Vernier Assist throttle is an OUTSTANDING throttle for formation flight. Like others already said, it is not your typical push-button vernier throttle (which should NEVER be use for formation flight). This is a normal push-pull throttle, but with the benefit of fine-tuned power changes by turning the knob.

As a flight lead, I love the vernier assist. If a wingman calls "Lead give me one," I give the throttle knob a full twist to the left, which in my setup reduces manifold pressure by 1 inch. For 4-ship echelon turns, I'll twist out one inch entering the turn for the sake of #4, then twist that inch back in upon roll-out.

It's a very smooth throttle, even with engine area temperatures up in normal operating range.

As for the "stock" throttle, don't bet on finding one. I had to order mine special using their order form's measurement guides.

ALSO,

If one did not already know, you wouldn't realize that it was "vernier assist". It works like a "normal" cable but MUCH, MUCH more **smoooooth**.

The vernier assist "magic" just works.

And I too have had GREAT experiences with them. On the phone, at SnF, at OSH, sales, tech support, you name it.
 
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