While setting up a DLE 20 on my Phoenix Extra, I have the following issues
I am setting up with a 2-56 pushrod on the throttle. Decided not to go with a nyrod setup simply because its not available right now. Initially I wanted to have ball links both sides to avoid metal to metal contact but the 2-56 Dubro pushrod is one side threaded.

1) I got this Dubro 2-56 ball link locally (see pic). Its snap on type, not bolt thru. I am concerned that if used on the throttle, it could disconnect due to vibration. But guys on the field told me it will be ok. Should I trust it? I dont want the engine cutting off while I am in a hover

2) The engine came with the metal throttle horn installed and a seperate fibre horn in the box. Should I use the metal or fibre horn (or should I mount the fibre horn on the metal horn and use that)? A longer horn will give a slower throttle response but will also require less effort on the servo

3) At the field they suggested I should either put a Z-Bend in the pushrod at the throttle servo horn or use a E-Z connector (you know, the brass type where the grub screw tightenes onto the throttle pushrod). The E-Z connector gives flexibility of throttle adjustment but I am not sure its secure enough. What should I do?

Ameyam

The "fibre" horn is supplied to lengthen the throttle horn on the carb and if used your metal to metal problem does not exist!
I use the fibre horn to allow a choke servo to be used. There is very little pressure on a throttle to servo linkage so I do not
see where you would have a problem.

repinfl,

Actually my bigger issue is that the ball link connection (http://www3.towerhobbies.com/cgi-bin...&I=LXD897&P=ML) feels delicate and the EZ connector (http://www3.towerhobbies.com/cgi-bin...&I=LXAHE6&P=ML) method insecure. I am worried that both could come off due to engine vibration

The idea of using the fibre horn to avoid the metal to metal contact is a good one, thanks for that idea, I feel a lot more comfortable with using a metal push rod all through now

Ameyam

Your making things harder than they need to be.
With tons of room in that fuse, you can easily relocate your throttle servo and shorten up the length of control rod needed;



See all that empty free space just in front of the wing tube?
Create a new mount for your throttle servo, and you'd be reducing the rod length around abouts 4"!
Shorter rod also equals less flexing of it.

No a1pcfixer, I tried that last week. Firstly I need to move the tank all the way back to the wing tube to try and get the CG. Then as you suggested, I would move the throttle servo forward to be flush with the canopy bulkhead. In fact, I even cut the ply that I was going to use. But just under that switch is the hole for the wing bolt. In this airplane, the wing bolt is tightened from inside. So if I move the servo forward, I cant get to the wing bolt. Thats the reason why I had to post for help again

Ameyam

I see a couple of issues here.

First. the length of the throttle horn is important. To get decent "thumb to throttle" response, you are far better off to use 100% of the servo travel for the throttle. This is the reason for the extra arm length. Use the additional arm.

The snap on ball joints are not a good idea for the throttle linkage. There is a high likelihood of failure. Use either a bolt though ball joint or a clevis. If using a clevis, use it on a plastic arm but expect the hole to wear fairly quickly. (My recommendation is to use a bolt through ball joint).

If you can not obtain some rod that is threaded at each end, Can you get a soldered on rod end? Some pull-pull connectors can be used for this as they have a hollow in the end. z-bends and easy connectors tend to get a lot of wear fairly quickly on gasser linkages.

A long metal rod going from the engine to near the receiver can be an issue for radio interference. Have you asked any of your flying buddies if they have a spare nyrod you can borrow until it becomes available?

aussiesteve,

those were the concerns that led me to post this thread. All the local ball links are either 2mm or 3mm. This pushrod is 2-56. The threads dont match and therefore I cant get a bolt-thru ball link locally. Getting from Tower is just too expensive. Imagine, its $7 shipping on a $5 item and that too through USPS! My next order is not very soon, so I cant get the ball links from Tower and my buddies dont have a nyrod spare.

By the way, the RX is not close to the throttle servo, its atleast 6" behind. Only the rudder servo is next to it (See pic)

If I go the clevis route, should I use this one? Thats available locally

http://www3.towerhobbies.com/cgi-bin...?&I=LXWH32&P=7

Ameyam

If I do end up having to order the nyrod setup, should it be this one

http://www3.towerhobbies.com/cgi-bin...&I=LXFU92&P=ML

or this one?

http://www3.towerhobbies.com/cgi-bin...?&I=LXFU90&P=7

Ameyam

You could try to get some 2mm or 3mm threaded rod perhaps and use the local ball joints. That rod may be available through a bolt supplier rather than an RC shop

Yes, those would be my preferred clevis (In fact that series of clevis is the only clevis I use these days). If you go the clevis route, leaving the throttle return spring connected will help reduce the rate of wear from Engine vibration.

Thats the idea- to leave the throttle return spring connected. That way, if the throttle linkage disconnects, the engine wont be out of control. I dont, however, appreciate it coming it to idle when I am hovering a few feet off the deck

Ameyam

Hi Ameyam ,
  I see that you have that EZ connector on that servo, temporarily I hope. Please resist the urge to use that as those things have no place at all in any powered aircraft, especially gassers. They will come loose, in more ways than one.
  Just an opinion though.

The Pamster

This is what you want
http://www3.towerhobbies.com/cgi-bin...?&I=LXD912&P=7

thepamster..............I must respectively disagree with your comments on the EZ connectors. I have used them in all of my planes since 1982 and I have never had a problem or failure with them. I have heard this over and over again.......that they are a problem............but I have never experienced a problem and I use them not only on throttles but other control surfaces as well. Of course a preflight everytime you fly......as you should.......helps prevent all sorts of problems like loose EZ connectors, loose hinges, loose engines and motor mounts....etc.

Cheers,
Andy

No way would I use a EZ connector on a gasser!! Lilke in the link below!

http://www.shopatron.com/products/pr...mber=121/101.0

Capt,n

That pic is from when the airplane was setup with a FS91SII. I have been using these E-Z connectors on my glow airplanes for a couple of years now. After a couple of failures initially when I didnt know the nitty-gritties of setting them up properly, I have never had any problems. However, the upto 90 size glow engines I have used them on supposedly dont vibrate as much as the gas engines. Thats my concern.

On Sunday, I had a lot of glitiching with my 72Mhz 6CHP and crashed my airplane in the process. I was flying my trainer as the field is still rough and grass uncut, its repairable. The TX is 4 years old now and I only use it on my older airplanes; I mostly use my 9CAP with 2.4Ghz Module. May be its time to give up on the 6c and go to a 8FG Super (9c is good but has limited model storage). Also, I am looking at a OS 33GT OR DLE30 for my MX2 (please suggest) and am thinking I will bulk order the Sullivan (http://www3.towerhobbies.com/cgi-bin...&I=LXFU92&P=ML) rods along with the ball lnks and stand-offs that I need.

Ameyam

No way would I use a EZ connector on a gasser!! Lilke in the link below!

http://www.shopatron.com/products/pr...mber=121/101.0

Capt,n
[/quote]

+1 ... vibration is one of the reasons. Gassers especially at low throttle have a lot of vibration.

Me neither!

Granted, the photo I'm posting is of a profile with a very short run, but it shows the preferred style of linkage for a gasser.
Threaded rod + ball link ends + small flat washers, with NO metal-to-metal contact.

I agree a1pcfixer. If someone can advice on the 8FG / OS GT33 / DLE30 issue, I am considering ordering the nyrods listed under

http://www3.towerhobbies.com/cgi-bin...&I=LXFU92&P=ML

Ameyam

The 8FG Super should be a great step up for you (it actually has 14 channel capability).
Tower has an offer running right now, of including a second rcv for FREE, until Oct 31.

I'd go with the DLE30 over the OS GT33

Those Sullivan nyrods will be fine, but do NOT use the included metal clevis on any throttle setup.
Use ball links as shown in my photo.

You'll also need to create a brace somewhere about mid-way, for the nyrod.
With a long run of nyrod, it may very well flex too much giving some undesirable results, unless braced.

the nyrods won'tneedbracingif he let the return spring hooked up to the throttle lever. The nyrodwill always be under tension.
If the spring has been unhooked from the throttlelever then by allmeans brace it.

Oh enginenot bought yet? DOn't unhook the spring

TimBle,

the bracing will be required. By default, the spring moves the lever back to idle not front to idle. In other words, the servo has to push to open the throttle (I hope I make sense), without the bracing the rod will just flex out of alignment. By the way, is the nyrod only for preventing metal to metal contact? If so, there is no point in getting it, ball links on both sides will serve the purpose. I may need to use 4-40 though as 2-56 full threaded isint available on Tower either

a1pcfixer,

the free RX is a gimic. By default the 8FG / TM-8 module comes set to 8 channels. To use a 617fs you have to set a small switch to 7 channels on the back of the thing (anyone with a 8FG please confirm this). The switch is so small, it will get damaged after a few times switching. I have a TM8 module on my 9cap and I sold off all my 617fs RX and bought 6008hs to get get around this problem. So the free RX is not desired. Wish Tower would deduct the price of the RX and ship me the 8FG

Ameyam

Correct.

Partially so, it also gives you a sleeve for the throttle rod(inner nyrod) to slide in.
Otherwise, you'd need something to support a solid rod if ya go that route.

Hmm, the one I'm looking at has no module, it's integrated right into the case;
http://www.towerhobbies.com/products.../futk8010.html

And comes with a R6207SB rcv;
http://www3.towerhobbies.com/cgi-bin...?&I=LXAVCR&P=V

I don't think TH/Futaba sells any Futaba FASST tx's with modules any more.
They might have a few discontinued they're unloading. Check their Scrath & Dent section.

Ask about such in the TH/Futaba Support section;
http://www.rcuniverse.com/forum/forumid_125/tt.htm

hmmm well I have my servo and throttle lever set up so the servo is pulling to open the throttle and the return spring closes the throttle so the nyrod is always in tension. I instaled the phenolic throttle arm reverser supplied with the engine. Thats how it works in my plane. No bracing required. If Ameyam has his different, then so be it. Just illustrating there is another way. But I guess I'll be told how wrong I am one more time

The T8FG is not a module radio. It is dedicated 2.4 so in order to use a R617FS you select 7CH from the Frequency menu. So you sold off the R617FS Rx's for nothing. The T8FG is completely backwards compatible with them. The free Rx will be useful.

Ameyam,

Imagine for a moment that the eng is installed.
Now measure how far it is from the throttle servo -to- the throttle arm, then subtract say 2"
which would be your ball link ends.

How long of a run is that in your situation?
My guess is around abouts say maybe 12-14"?

A bit longer. I think with the 12" 4-40 I was 4" or so short. I cant check right now, need to go to work (its 7am here). The threaded coplers require t be soldered on the socket end, have never done that and wonder whether its advisable. Do I simply use electrical solder?

I am considering metal pushrod all through with ball link both sides. May be I could get a 2-56 threader jig. It would be useful elsewhere as well

http://www3.towerhobbies.com/cgi-bin...?&I=LXR765&P=7

Ameyam