Nice Foamy Pushrods

 RCG Maven balsa or carbon has some nice shots of foamy pushrods. Here's how he does it.

Start off two two pieces of music wire, one with a Z bend and one with an L bend. Attach the Z bent wire to CF rod with CA and shrink tube .

Round the other end of the CF rod with sandpaper and attach it to the L bent wire with silicone fuel tube.  Don't glue it, this allows you to adjust the pushrod.

Stick the L bent wire through a piece of rubber band. Attach the L bend to the servo horn, and stretch the rubber band around the music wire as shown.  Tighten the fuel tube with a zip tie if it's loose.

Stabilize the pushrod with a zip tie glued through the airplane body if there's flex when moving the control surfaces.

If you don't have any silicone tube handy you can zip tie a rubber band to the rod.  Here it is holding the L bend wire to a bamboo skewer pushrod.  BoC reports that it's tight enouch that he has to use needle nose pliers to adjust.  Notice hi popsicle stick control horn!

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Push Rods Revisted

Filling in a bit more of what I have learned about micro pushrods.

• For small flyers, the reference standard seems to be the Du-Bro Micro Pushrod System #852 (30" x .032"):

New Du-Bro Micro Pushrod System. (2) 30"x.032 pushrods, (2) 30" pushrod housings and (2) micro E/Z Links and (2 Mini E/Z Connectors. Great for indoor and park flyers! 2/pkg.

• The EZ links are: Mini E/Z Connector (Cat. No. 845)
• Hobbyking links come in 1.5mm and 2mm.
• The EzFly kit comes with 1.5mm carbon rod, 4 wire z-bends, and heatshrink.
• Heatshrink z-bends to the carbon rod, and heat.  Put a drop of CA and allow it to wick into the heatshrink
• Don't try putting the z-bend in the center of a hollow rod, it won't stick.
• You can use a z-bend on both sides of the push rod.  Center the servo, align everything, and heatshrink the z-bend in place.  Once you're convinced everything is properly aligned, Apply CA.
• Somebody uses TIG welding wire for the rod.
• A lot of people use 1/32'' (almost 0.32) piano wire.  These need to be fed through a housing to maintain stiffness.  Attach the housing to the plane somewhere.
• The z-bends can be made from a paper clip or .072 piano wire.
• For a housing, try plastic coffee stirrers. Heatshrink together if you need them longer.

Push Rod Weights

• 1.5mm CF
• 2mm CF
• 3mm hollow CF
• 1/32'' piano wire
• z-bends
• heatshrink
• coffee stirrers

Making a Carbon Fiber Push Rod

What you need:

• carbon fiber rod, 2mm, cut to length
• 2 pieces music wire, .032i inch (.81mm), 2 inches each
• screw thing:                1.5mm 
• 5 minute epoxy

Make the push rods:

• measure length required
• cut CF rod, length = measured length - 1 inch (wire will make up remaining length) using dremel cutoff wheel.
• cut 2 pieces of wire, 2 inches each
• put a tiny irregularity (bend) in one end of each wire.  this will go into the CF tube, and provides something for the epoxy to hold against.
• clean wire
• mix 5-minute epoxy
• epoxy wire into CF rod, 1 inch.  don't forget to put the tiny bend into the hole.
• after the epoxy has dried, tug on the two wires to make sure they don't slide out of the hole.  If they do, you didn't do a good job on the epoxy.

Install the push rod:
measure length required

• Z-Bend one wire.
• attach z-bend to servo. (then you don't have to drill out hole in servo arm).
• drill horn to fit 1.5mm screw thing
• attach screw thing to horn
• put straight wire into screw thing.  you can get clearance by pushing servo arm away from the control surface, and pushing the control surface away from the servo arm. this will give you just enough clearance for the wire to go into the screw thing hole.  if there's not enough clearance, your wire is too long and you should trim it down to the proper length where it just fits in.
• turn on servos so they are centered
• align control surface to neutral position
• screw down screw things

Hint: if you know you're going to be needing several sets of push rods, make all of them at the same time, factory style.  You'll save lots of time.

Nice bamboo skewer pushrod

Nice rcgroups post detailing how to make a good bamboo skewer push rod.

zbend a paperclip

round-nose pliers to make a "spring" on other end

cut skewer to approximate length

screw the springs onto the bamboo, threaded onto skewer

adjust distance by screwing spring

trim and heatshrink

adjust by removing heatshrink and screwing in or out