Balsacutter

My Feedback: (3)

Building a Goldberg kit, arrived at the usual 3/8 sq hard balsa pushrods. Threaded wire links attached to the wood with carpet thread and glue. Ugh.

Pros: Cheap, easier to install than Goldenrods (no interior anchor points required), fairly stiff, pretty light really.

Cons: Servo thrust delivered off-center of the square section which bothers me, lots of wire bends which bother me, ultra low tech, and butt ugly.

I like to feel good about what I build, and these look like they're left over from the rubber-driven escapement era. (There's one you young studds can puzzle over....)

What are your favorite pushrod solutions?

(Solutions must include a way to connect to the servos and horns. Not enough to just say 'carbon fiber tubes rock'.)

js3

My Feedback: (3)

Carbon fiber tubes rock!

Seriously, this is my favorite type of pushrod. See this how-to [link=http://www.darrolcady.com/Carbon_Fiber/carbon_fiber.htm]here[/link].

As for the ends, I like Z-bends at the servo end and various suitable hardware at the control surface--it just depends upon the situation.

kdheath

Central Hobbies CF pushrods, titanium ends, and ball links. Easy and bulletproof.

http://www.centralhobbies.com/contro...e/carbrod.html

Dr1Driver

Look at Dave Brown arrowshaft pushrods. I LOVE Goldenrods for certain applications, expecially if the wire ends have bends to make that the curve of the rod will eliminate. I've also used wire-in-a-tube (both 2-56 and 4-40), straight wire (4-40) for VERY SHORT runs, 1/4" bass/wire (2-56) rods (I have a much better method of attaching the wire than the old "wrapped thread" trick), all with good resuklts. You have to pick the best linkage for your particular requirements. Goldenrods and wire-in-a-tube both should be braced every 3" - 4" inside the fuselage. They're are a little more work, but make a VERY NICE appearing and bind/slack-free installation. Today's Goldenrods do NOT have the expansion/shrinkage problems the nylon rods of yesteryear did. A few years ago, I did a test of a 24" piece of yellow rod. From a temperature difference of 0 degrees F to 200 degrees F, I noticed a length change of only 1/32".

Dr.1

DavidAgar

My Feedback: (108)

I still use dowels and wire ends. They are very functinal and they can be installed without wire bends if they are planned out as the fusealage construction is done. Good Luck, Dave

cyclops2

Almost every sport plane can be set up the best way.
If the servo is less than 6" away from the other horn.
Then it is a short threaded piece of threaded rod with ball links or clevis and snaps.
A long extension cord is OK. I have 4' extensions in boats that are huge electric motors and no problems.
Worried anyway? Use a photo optic isolator on long runs.

D Bronk

PULL-PULL CABLES

MinnFlyer

My Feedback: (4)

As one who learned to fly in the "rubber-driven escapement era" I say "what difference does it make"?

They work well, and they're not visible (Unless you take the wing off and look down the tail). If that's what the MFG send, that's what I install. I see no reason to change them.

Of course, if they supplied some really soft balsa that bends too easily, then you could replace them with CF or a 5/16" wooden dowel

Dr1Driver

The manufacturer doesn't always send the best linkage for the application. Often, it's what's cheapest for them to include.

You're showing your age with that "escapement" crack. I remember seeing escapment RC during my CL days, but didn't get into RC until after proportional was in vogue. I DO remember the Kraft Signature Series, Logictrol, and Heathkit, though. Linear optput servos, engines with exhaust wipers (not mufflers), and silk and dope.

Dr.1

MinnFlyer

My Feedback: (4)

Ah, the good ol' days

cyclops2

In the good old days NO one had to wait to crash their plane.

sscherin

My Feedback: (1)

I've mostly used Golden Rods.. My big problem with them is I don't like seeing a big yellow thing poking out the side of my plane..
I prefer to stop the plastic rod inside the fuse and exit wit a metal rod.

The only problem there is finding assorted length rods rods threaded on both ends (didn't Sullivan used to include those), using Z bends (no adjustment) using all thread (ugly) or soldering on a clevis (again no adjustment)

What I did on the last one was get a 2-56 die and make my own double ended rods..
Good idea till you pick up a couple single threaded end 12" 2-56 rods and find the rod diameter isn't enough to cut full depth threads..

Enter Gorilla glue! even on an undersized rod you cut enough thread for the gorilla glue to get a good bond.

So thats my thing for now.. Gold-N-Rods with custom end wires glued into the rod with gorilla glue.. Clean looks and easy.


About 20 years ago I did buy some great ends for square wood push rods.. Man they worked great..

It was a plastic end cap for the wood push rod with the metal rod bonded on center in the end.. Just epoxy em on and you were good to go.
I can't remember who made them though.

yellerchamp

My Feedback: (42)

Just curious what goldberg kit is it, I have a t-60 on backorder. I also have used the dowels in several and have been happy with them, but everyone is different otherwise we would all be flying cubs

jstrawn

I used the square Balsa on my Ultimate. With a Supertiger 90, there was so much flex in the rods that I barely had enough elevator to take off! In come the CF Rods, and there is absolutely no flex at all.

Most of the flex was in the bent 2-56 wires, but there was some in the balsa as well.

FlyingPilgrim

My Feedback: (26)

I've been using pull-pull on rudder and the fiberglass Dave Brown for elevators on my last two planes and like them. My next one I'll try some carbon fiber rods. I've used 2-56 and 4-40 rods in plastic sleeves, wood dowels with 2-56 rod strapped to it, and all worked well. I don't think it matters much as long as you use the appropriate strength system for your requirements. Of course the all-out competitors may require the utmost strength and low weight of CF/titanium, but for sport, I don't think it matters that much if installed correctly!.

JMOR06

I like the sullivan carbon filled Precision Rods. Almost as easy to use as nyrods and much stonger.

http://www.sullivanproducts.com/GoldnRodMainFrame.htm

Jeff

Cyberwolf

My Feedback: (4)

ON 40-60 sized planes I usually use the metal rod in the tube and put several anchor points to prevent flex. Larger planes is all direct linkage hook ups as short as possible ,pull-pull on the rudder if the extra tail weight is not needed.
Heres one thing I do ,at your LHS they should have the metal rack I use round alum tube thick walled ,if you can find the correct size a 4-40 tap will make perfect threads.See the example below.Couple the clevisand rod useing a short piece of 4-40 threaded rod a drop of thin CA will insure it never to come unscrewed .

CafeenMan

I don't have a favorite pushrod. I use whatever I think is most appropriate. Wood pushrods are very good if properly constructed. In fact, a lot of people have said not to use wood because it changes dimensions with the climate. I've said the same thing even though I can't prove it and am not a good enough pilot to tell if it did happen.

What I suspect is that a wood model should have wood pushrods because a wood model will probably expand or contract much closer to what the pushrod does than say a wood model with a carbon fiber pushrod.

All that being said, I'm moving more and more toward using pull-pull because it's more positive and much lighter. I have been using the new fishing lines because it's easy to find and more than strong enough. I'm talking braided lines, not braided cable. Stuff like Power Pro works well.

Gray Beard

My Feedback: (-1)

I have A couple of friends that are Archers and shoot two sizes of CF arrows and they save me there broken shafts and I make my own from these. Straight, no flex and need no support. I make up my own pull/pull systems with plastic coated stainless steel fishing leader.

Balsacutter

My Feedback: (3)

Wow, what a great thread.

I checked out the web pages people referred to and they opened up a whole new world.

Yellerchamp, it's just a clipped-wing Goldberg Anniversary Cub I'm building so the pushrods aren't as critical as some F3A pattern screamer, but with every model I try to wring out what I didn't like about previous projects. With this model I'm experimenting with hinges (I'm trying Robart Hinge Points) and thinking about pushrods other than Gold N' Rods.

My next project is gonna be a low-wing aerobat, so the Cub is a testbed for new techniques.