DIY Push Rods / Linkage Stoppers

skeplin

Senior Member
It seems that every time I go to place an order with HobbyKing, linkage stoppers are out of stock. For my first scratch build, I simply used lineman pliers to bend piano wire into a "Z" on both ends. While this menthod works, it's a bit of a pain to attach to the control arms and it's looser than than I would like it to be.

So what's the secret to success when making your own push rods? Are plastic or metal clevis recommended? Do you buy pre-threadded rod? Any secrets to bending the "Z"?
 

Craftydan

Hostage Taker of Quads
Staff member
Moderator
Mentor
A while back there was an article posted on fly-tying two pieces of piano wire into one pushrod.

http://flitetest.com/articles/how-to-make-detachable-control-rods

Haven't built one of those, but have used it to tie on a stiffener and tie together structural rods.

As for Z-bends, I cheat: http://www.hobbyking.com/hobbyking/store/__6283__Z_bend_Pliers_Heavy_Duty_90deg_up_to_1_16.html

They come in heavy at 400g shipping weight, but even then they've still cheap, and they've become a handy finishing tool.
 

tramsgar

Senior Member
Z-bends are ok but I really like to put a linkage stopper at the servo side if I use them. Trimming goes from pain to smooth.

Regarding clevises, I recommend cutting a 3 mm piece of silicone tube (or similar) and pull it over the clevis so it won't open during that high G pull up. Especially those made of plastic. (Just ask my Bixler 2.)

IMAG1660.jpg
 

xuzme720

Dedicated foam bender
Mentor
Z-bends on both ends can be adjusted if you add a v-bend to the pushrod somewhere. Adjustment is done by widening or closing up the "v". I do prefer the linkage stoppers though, even with the z-bend pliers. I can say this for them, as long as you can hold on to them (seems like everyone is always trying to borrow them) they will last forever. Had mine for at least 15 years and they still look pretty good and work just like new!
 

skeplin

Senior Member
Bummer on the crashed Bixler! I haven't had my z-bends fail yet though they seem...inaccurate. I've seen them get stuck before on the ground. Good thing I'm flying something easy (FTFlyer).

Any recommendations on where to get linkage stoppers?
 

Craftydan

Hostage Taker of Quads
Staff member
Moderator
Mentor
Dubro sells them at almost all LHS under the name "EZ Connector". I think I've seen they have three or four sizes of them -- you'll want the smallest they have. usually in packs of 2 or 12 at $0.75-1.10 a link. highway robbery at that price, but at least cheap highway robbery.
 

tramsgar

Senior Member
I bought mine here, and again as Crafty says, get small ones. HK also has linkage stoppers, but the selection is small and availability bad.

I really recommend the ones with grub screw on top (for the rod) and an e-clip at the bottom (holding onto the servo arm) because they won't come loose by themselves that easy and require no thread lock or CA.
 

tramsgar

Senior Member
The e-clip is the C-shaped part to the lower right (below the black grub screw). I prefer them as they don't unscrew (other linkage stoppers have a screw instead of a clip and it has to be glued). Hope that helps.
16-502.jpg
 

xuzme720

Dedicated foam bender
Mentor
A C-clip with a finger in the middle. It's a a slip-on connector as opposed to a screw/bolt mounting.

like: http://www.hobbyking.com/hobbyking/store/__8414__linkage_stopper_d2_1mm_10sets_.html

Edit: Dang. Beat me to the punch!
We used to call them "jesus clips" when we ran them on the 1/10 scale cars. They were on the steering kingpins and if you clipped a board or hit something just right, they'd come off and your front wheel would be dangling and you'd usually say"JESUS!" ...
 

tramsgar

Senior Member
We used to call them "jesus clips" when we ran them on the 1/10 scale cars.

Well all I know is anyone should keep a healthy stock of them in various sizes because they tend to pop up (or in your case, off) just about everywhere in the hobby. =) I like them because whenever they come off, it's probably for the best.

(Actually had one of those "Jesus"-moments the other day when my kid ran my 1/10 SCT into a concrete stairs step. Didn't feel touched, tho.)
 

andy_spoo

Member
The e-clip is the C-shaped part to the lower right (below the black grub screw). I prefer them as they don't unscrew (other linkage stoppers have a screw instead of a clip and it has to be glued). Hope that helps.
View attachment 12568

I've not seen this type before. But I've been using thread lock on the threaded type. Seems ok SO FAR. But I like your type better. I'll have a search for them.
 

DDSFlyer

Senior Member
the LHS guy gave me a great idea for this as I was building my scratch build FT cruiser...pushrod/clevis set for the super cub! They are long enough to be trimmed for most all size control arms, have an attachment for the control arm on the control surface and you can trim to your length and make a Z bend for the servo. Plus it's 99 cents for 2 at the LHS, GENIUS!
 

xuzme720

Dedicated foam bender
Mentor
Thanks for the info. But as usual, after checking if they're available from the UK warehouse, they're not even listed. It's often like that, or zero stock for so many items from the UK warehouse. I don't know what hobbyking are up to.
I've seen them on eBay as well, only not as cheap...
 

fishermansteve

Junior Member
can sum one tell me how you fix the c clip on the end of the linkage stopper it is drive me mad my fingers are so big i cant seem to manage it i have tried lots of things even my wifes eyebrow tweezers PLEASE HELPPPPPPPPPPP
 

Timmy P

Member
I gave up on using adjusters and went straight for the double z bend. Most of my planes now have flaps so I'm using 6 servos. At that point I'm using 2 packs of Du-bro adjusters and thats close to 7 bucks.. Twice the cost of my airframe lol. So what I do is. With the controller ON and trims at neutral, and servo control arms centered.

First step is, don't glue anything at first. I make a snug hole for my servo and get my FT servo horns pressed in. Then I use Z bend pliers to make the double Z pushrod and put it in. Ill make a small adjustment to the servo horn placement, then glue it in. And if you still need more adjustment you can slide your servo a bit to trim it in and glue it.