Engine Control Linkages - Firewall Design

[schaumr]

Hi all,
I am acquiring the various firewall components I'll need, and I have been told to get a throttle cable with a threaded end to be able to finely adjust the travel. However, these cables typically come in fixed lengths, and to the best of my knowledge, cannot be trimmed down to fit. Do you just buy the closest size to what you need and have the extra length travel aimlessly around the cowling?

In a related note, may I ask those with operational aircraft to share photos of your firewalls? I'm trying to gauge where to place things and seeing others' examples are always helpful. I already have some photos of older Skyhawks and Pipers, but I'd like to see more 'modern' intallations and innovations.

Many thanks,
Rob

[irishfield]

Conical mount or dynafocal Rob.. and I'll dig through what I have.

[schaumr]

Neither Wayne.
It's a 'bed' mount for a Corvair.
See my page:

http://mykitlog.com/users/display_log.p ... 9827&row=4

[snowyriver]

Hi Rob,

I know you've been on my site before; if you go to 'firewall forward' page you can see a few photos of what I did. It's mostly a copy of what most did. I'm guessing that any Lycoming eng throttle cable measurements aren't going to work with yours. I mocked mine originally with some #12 wire I had lying around. Just bend it up as you need to and then measure. Have fun! Craig

[Dick]

I agree cables with rod ends or some call them "Monoball" are very nice, they come in about 6" differant lengths. Red for mixture, Blue for prop, Black for throttle. They can be in a standard push pull (My prefferance for throttle), or vernier for mix & prop.
For the routing try a heavy "bailing wire" to get a smooth routing and length. When installing add protectife sleaving in any area things might rub.
McFarlland, Aircraft Spruce, are good sources.
Dick

[schaumr]

Thanks for the feedback thus far. The pre-cut throttle cables with the threaded ends are around $80 at aircraft spruce but the shortest ones are at 3 ft, which is too long for me (I only need 2 ft). You can buy the "Van's" cables, which are essentially custom fabricated versions of the above (you give them the exact length and stroke you need), but those are $190 ! :crazy: That's the same price as a certified Cessna unit!!

So I guess I'm asking: is this the price folks are used to paying for a throttle cable? I thought this was 'experimental' aviation?

And I'm also wondering if you all purchased the associated cable-install hardware (rod ends, lock nuts, etc...) separately, or have you seen these come as kits from some suppliers?

Just trying to make sure I am aware of all options.

Rob

[Coastflyer]

I used the ACS brand. I think the 3' one was the perfect length by the time you make the S bend to line up with the carb. It's nit a straight run from cockpit to carb. Having said that, I wouldn't use
ACS ones if I did it again. They feel kind of "cheap" in your hand. The knobs have some end play, and just don't feel that solid. I would pay more for better controls. Actually, if I could do it over I would use a quadrant.

[Coastflyer]

Also, if you get their mixture control, be careful when you're messing around with it. There's a ball bearing in there that's part of the vernier mechanism, and if you pull the control out of the housing too far the bb will go bouncing away.

[bhewlett]

Jesse, it sounds like that comment comes from experience.............

I haven't got to the cables yet but I have changed them on some other planes.
To be honest the throttle and mixture cables are one of the places I wouldn't cheap out on.
That is from experience as well.


Brad.

[Coastflyer]

Yes, my bb fell out while I was installing the mixture control. The cool thing is that I wasn't aware that it had gone, or that it was there in the first place. I was puzzled why the vernier didn't work, and was ready to send it back to spruce, but I looked at it a while and decided there needed to be a bb in there. I started looking all around my shop, and found it! How's that for having faith in your own ideas?

[bobp]

Throttle & mixture cables - sourcing ...

Some of the guys here found great service & cables with
fork ends at a local tractor supply house ! They would custom
cut to whatever length you wanted, fasten on the forks or balls,
and only charged about $35 !! They were better quality than
the 'aircraft' vernier cables, and a lot less money !!!

Officially, they were "controls for Power Take_off drives"
for tractor mowers .... ;-)