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Clamp for non-threaded push-pull cables (McFarlane)

jwyatt

Well Known Member
Does anyone have a source/part number for appropriate clamping hardware to use on the end of a push-pull cable that is not equipped with a threaded section?

Specifically, I'm considering swapping out my throttle control with the McFarlane vernier-assist. However, their assembly doesn't have the threads at the end to secure it in a hole, as my current one does.

I'm assuming I would need something along these lines:
http://www.aircraftspruce.com/catalog/appages/controlmounts.php
...unfortunately, Spruce doesn't show any dimensions. One would assume that McFarlane would have an appropriate piece, but I see nothing on their site.

Thanks in advance to anyone who has been there, done that.
 
Same problem here

I was facing the same problem when installing a McFarlane push pull cable
for my purge valve.
I am not sure why you would want to switch from a "normal" throttle cable to a McFarlane without a threaded end?
They certainly are available in all shapes and sizes, friction or vernier whatever you prefer.

After using a compression type connector that failed at about 40 hours I decided to make up my own adjustable clamp.
As you see in the picture it consists of a fork rod end and a rod end bearing connector, joined with a stud or you may find a male and a female, it's what I had laying around.
The bolt through the fork end is drilled to fit the McFarlane cable and clamped tight between 2 washers. There are no kinks for the cable "wire" to eventually break. The purge valve is simply an on and off actuation and does not have to be manipulated as much as the throttle.
I would think twice before installing something other than a standard throttle cable.




IMG_2573.JPG
 
Thanks, Walt. I just need to find that part in a large enough diameter; the spec on the cable indicates that the sleeve that needs to be clamped is .375" OD, and those clamps are only listed for 3/16 and 1/4 diameters.

va-cable.jpg



I am not sure why you would want to switch from a "normal" throttle cable to a McFarlane without a threaded end?
...
I would think twice before installing something other than a standard throttle cable.

To be clear, the cable I'm looking at does have the threads on the end of the push-pull part to attach a rod-end bearing. (See image above from the spec sheet). The threaded part that's missing is the bulkhead thread to secure it to the fixed bracket aft of the throttle arm...at left in below photo (picture is of my existing install with an ACS cable). I'd agree that a bare-wire end should be avoided on the throttle; I used threaded cables on my purge valve, too.
DSC08132-300x225.jpg
 
Solution?

How did you end up solving this? I'm getting ready to swap out the throttle & mixture cables for the vernier-assist versions, and just realized they don't have the threaded bulkhead section to anchor to the cable mount brackets. To be clear, both cables have threaded rod ends to attach to the AFP control linkages.
 
Something I've been doing is use an appropriate sized adel camp without the cushion. Clamp it up nice and tight around the cable with a bolt/nut, vice grips or vice, then use a dull flat screwdriver and a hammer to form a depression into the groove in the cable sheath.

Lasts forever and is inexpensive and light.
 
Our new build uses these cables----the mount is simply a short piece of angle alum stock, has a slot milled in one side that fits the groove in the cable housing end. There is a small hole on either side of slot for running safety wire to capture the housing in the slot.

Simple, cheap, light, and easy.
 
Specific alloy?

Our new build uses these cables----the mount is simply a short piece of angle alum stock, has a slot milled in one side that fits the groove in the cable housing end. There is a small hole on either side of slot for running safety wire to capture the housing in the slot.

Simple, cheap, light, and easy.

Mike - thanks, that sounds like the way to go for this. I'm a modifier, not a builder, so my knowledge of aluminum alloys is lacking. Can I use aluminum angle from the aviation aisle at Lowe's for this, or do I need to drive down to Metal Supermarket & get a specific alloy? If so, which one? It looks like they stock 6061 & 6063.
 
I have made clamps for these using an appropriately sized AN firewall fitting. I cut slot the end to make a collet out of it, and used a B-nut to tighten over it.

open
 
Mike - thanks, that sounds like the way to go for this. I'm a modifier, not a builder, so my knowledge of aluminum alloys is lacking. Can I use aluminum angle from the aviation aisle at Lowe's for this, or do I need to drive down to Metal Supermarket & get a specific alloy? If so, which one? It looks like they stock 6061 & 6063.

I would stay away from hardware store alum angle stock for this-----you do not want to take a chance of it breaking.

Aircraft alum angle has an inner radius or fillet that greatly strengthens the area where it makes the 90* bend.

shopping
 
The groove in the cable is 1/8" so I cut the slot in a chunk of 1/8" bar stock with a couple safety wire holes to keep the cable in place. Bolt the bar stock piece to the rest of the support. Done.
 
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