Throttle and Mixture Springs

[wybenga]

We are currently going through the final details of rebuilding N25EZ SN25, and need to find a set of springs for the throttle and mixture cable return.  We have been unable to locate the company listed in the plans, so where do ya'll get these springs

Thanks in advance

Jack

[Delta Mike]

ACE Hardware stores have a very nice selection of springs.

[D]

Howdy Jack -

Elliot's Hardware (Coit and Park) is another local option if ACE doesn't work.  Hope to see/hear that VEZ in the air soon!

D

[Ghost-Rider]

Delta-Mike is correct;

Ace Hardware has an excellent selection.
If you don't have one near by, you can order via the web, by logging into acehardwareoutlet.com

In the search window, type in "SPRING" and you will get approx 10 pages of the various springs they sell.

I would venture to say; Ace has more On-line than in the local stores, unless you're lucky enough to have a large Ace Hardware in your area.

I just re-did my return springs, and found it difficult to find the exact length and tension for my 0-200 application.

My solution was to incorporate a, Spring / Cable combination.

I found a spring I liked, (good length and tension) and made a cable with swaged ends to close the gap. The spring that was previously on, had way too much tension and would cause the throttle and mixture to creep.

Ghost

[Charles Davis]

As long as you are in there, have you considered converting to push-pull cables instead of the spring system?

[Ghost-Rider]

Charles,

I did consider the Push-Pull cables, and I would agree. it's a better configuration in comparison to cable & spring.

However, the PP cables aren't cheap, and significantly heavier than the Cable and Spring Config., and I imagine you would have to change the throttle control head.

I configured mine with dual-springs from different anchor points giving me a redundant system I am very comfortable with.

I am posting several photos of other VE's spring return configurations I saw at the 2006 Sun & Fun on my web page ( Construction Log / Return Springs).

I guess the point is, there's several ways to skin a cat, and their all good as long as they a safe.

Ghost

[Drew]

The only caution I would give with the springs is that if you CAN'T actuate the throttle/mixture without the springs, you NEED push/pull cables.

If you don't have an accelerator pump (mixture/throttle feels flimsy), you can use springs.  But the check is to remove the springs to make sure that you can get actuation with a spring failure (even a multiple spring failure).  The purpose of the springs is to put tension on the cable to get rid of the spongy feeling.  It is not to actuate the mixture/throttle in the other direction.

To convert mine, I used the same brock throttle quadrant and cut new throttle arms per Central States articles.  Converted the brock quad for push-pull.

[Ghost-Rider]

Drew,

Which CSA article was the one that had the information on switching the cables?

I also have the Ken Brock throttle, how ever my cables are multi-strand, spiral wound type.

Are you saying you were able to switch the multi-strand over to solid shaft cables?

Spruce sells the Bowden, Solid Wire Ends cable for $1.50 per Ft. PN/05-15500. Is this what you used?

If this is the case, I would definitely be interested, and I wouldn't have a need for return cables.

Ghost

[Drew]

In this article I talk about some tips and tricks in getting the cable to go through the correct spot in the firewall:  http://ez.org/v-web/bulletin/bb/viewtopic.php?t=541&highlight=cable

Unfortunately, I am not at home and can't access my cheat sheet that shows me the cross ref to which CSA article----send me and email note to remind me and I'll send you the ref.

And for whatever reason, I am not able to pull up the spruce PDFs at their website.

So from memory...
-remove brock quad from aircraft (I think there are 6 bolts behind the panel---2 for the mix, 2 for the thrott, and 2 for the carb heat
-unbolt the big bolt that goes thru the whole thing
-You remove the bike cables from the brock quad (it is a wire attached to a small cylinder----like you would see on a bike brake caliper).
-You remove the knobs from the mixture and throttle arm (they just pull off)
-You remove the throttle and mixture arms from the quad (can't remember if they are rivited or screwed
-you make new aluminum arms---but these are shaped like boomerangs-template in CSA.  Three holes get drilled---one at each end of the boomerang and one in the center.  The center hole is where the big thru bolt goes back in.  The top hole is for the old knobs that you salvaged off the old arms.  The bottom hole is for a "fork" (clevis?) that bolts to the top end of a push pull cable (one end of a cut to your own length push pull cable has a bolt end----the other is just the solid wire).  So imagine that you push the throttle forward, the arm rotates around the bolt, the other side of the boomerang goes aft which pushes the fork which is bolted to the push pull cable.

There is a device that spruce sells that is meant to hold the cable in place.  I floxed that device to either the fuselage wall or the armrest---can't remember.

On the other side of the wire (read my other post about getting thru the firewall---learn from my mistakes), you need to attach a wire grip (spruce) which allows you to connect another fork on the back end.  There is another grippy type thing that spruce sells (blue in color) that you can attach to the carb bracket that keeps the cable from slipping.  

I did not use the plans built carb bracket.  I used the 0320 carb bracket that you can get from Vans.  You will want to turn the carb 90 degrees from plans so that you get actuation fore and aft (instead of left and right).  I had to bend the Vans bracket a little bit to get it to work for me.

I am not sure about your part number since my govt computer won't let me look at that version of adobe.  However, I did use solid wire cables from spruce---get more than you need then cut to size.

Unlike the bike cables, you will want to make as few bends as possible.  The BEST way to drill the hole in your firewall for the cable is to use some scrap cable and wire.  Attach the wire grip and fork---attach it to the carb---run it thru the cable sheath grip on the vans bracket----and see where it wants to go thru the firewall.  If you drill in any other spot than this, you WILL NOT be happy with the friction in the system. Then make an easy bend to the fuselage side.

Once you have the final assymbly all done---you may want to go to the wire grip and make sure that it can't come undone.  It sticks REAL good---but you may want to put epoxy on it or something-----not on the wire but on the threads of the thing that puts pressure on the wire---you don't want it to back off.

[Drew]

CSA 61 page 13 and CSA 66 page 12 talks about throttle/mix arms and push-pull upgrades