Rudder and Installation

Some reflection about the installation of this rudder will conclude that battleship construction is not needed. It is supported at two points and is therefore, rigid in its position and under little stress by the water or the servo. Tradition in hull supports and resin pours are overkill and added weight. This was a masterpiece of design and forethought by Bob Kjellberg to the hull fit and installation process.

However, having said that, a detailed account of the rudder installation is needed to finish the job that mold building could not do; this because of the location and angles involved. So the section here becomes longer than that of the EC12 where a rudder can be installed during commercials on West Wing.

The Rudder Process
Due to construction time limitations last Spring the first two rudders were hand made, faired and finely finished. They were both "plugs" in the sense they were not made from a mold. Likewise, Bob Kjellberg made the first two shoes that would hold the rudders at the base of the keel from solid brass stock.

  
  

A mold was made off one of the originals with standard techniques, a specialty of Dave Brawner, who also made the molds for the hull. The process is the same as presented for the hull on other pages.

 

This is not a small rudder by standards for most boats. The shoe was needed to stabilize the rudder at the base rather than having a massive rigid structure held by a few ounces of resin in the hull and at the tiller. Rubber molds were made of the brass shoe to produce a solid fiberglass one. Weight is not a factor and the loads not thought to be that great. The glass shoe retaining hole for the rudder shaft was sleeved to act as a bearing and prevent chatter.

  

The rudder is 13 x 5.5 inches with a 24 inch stainless 1/4" shaft and sleeve to fit. The tiller was fashioned from brass. The whole affair weights 17.1 ounces.

   

Fitting
The designer of the mold prepared the hilt of the rudder fairing, where the shaft and sleeve would enter the boat, with a cutout section that is plainly visible on the hull. The hole will appear when this is cut away and only minor trimming is needed to fit the shaft for a flush fit of the rudder in the fairing. Then you will see other minor filing needed for the rudder hilt to fit into the cutout area that will seat the shoe and provide symmetrical rudder deflection. The blue tape you see is three layers to provide separation during the fitting. It is easy to see what is needed as the bearing in the shoe sets the standoff.

 

Preparing the Hole
It is noted in the photo above that the hole is elongated and actually runs up the fairing about 3/8 of an inch. With the rudder taped in place, a photo from the inside plainly shows the rudder hilt where it would be exposed to re-enforcing resin. The fairing needs to be extended to at least the right angle of the ledge that meets the rudder (the other leg of the "V").

 

 

Rather than do a single taping to resin in the rudder, the fairing extension is done first. A piece of 1" blue tape was curled into the exterior of the fairing and extended through the hole. The rudder and shoe were taped into place to form the that tape. Thickened resin was then applied to the inside onto the tape and hull to just beyond the bottom on the "V". Only enough resin was used so to create a protecting barrier to the rudder during the final installation of the rudder when resin is filled in around the sleeve.

 

When the resin was well beyond tacky and the stick was stuck in the mixing cup, the rudder was removed and the tape peeled off. Later, the rudder was slipped back in and no trimming was needed.

Installing the Shoe...Hehe!
If someone says, "Well, I just did this and that...," you can be assured it is like, "Man do I have a good deal for you." Installing the shoe is like decking. You prepare, think and think again and then do a dry run. Peer down into the cavity confines of the aft keel area and some interesting questions will float to the surface.

To lessen your running around, here are some things you may not have in your shop inventory. Two SS flathead 10-24 x 1" machine screws, Two wing nuts to fit, Vaseline, a hose or tube extension for the syringe and a bit of clay. And you will need your roommate.

The white shoe casting has countersink dimples as the rubber mold was made from the brass one. With the shoe and rudder carefully taped into place, the dimples were pilot drilled then finished with a #11 bit. You should be able to push the screw through the hole without turning it. Cover a long Phillips screwdriver tip with sticky tape and stick the wing nut to it. Lower the nut into the keel till atop the screw and have your roommate try to seat it. Be nice now. Do the rear one first so you have to be extra nice. You may have to trim away some resin and seam tape from the joining of the halves and that will cause you to be double nice. If you try to use hex nuts, others will revere you to the standing of Job.

   

When you breeze through this test remove everything and clean the keel with Acetone on a rag and stick. Forward of these holes build a dam of clay to hold the resin goop from running off. Sink the screws into the Vaseline and push them through the hole. Do not turn them. Install the wing nuts to snug.

 

Mix the resin with fiber but less viscous than with normal gluing. You are pouring this time. Push this through the syringe into the cavity over the wing nuts. The aft wing nut seats higher than the other as you see here. Remove your stuff and don't touch anything and make sure nothing or anyone will touch it. Your mantra till the next day will be, "Please don't stick to the threads, please!"

   

Install the Rudder
Tape the hilt of the rudder fairing with a single piece. Slit it to allow the shaft and sleeve to pass through into the rudder compartment. Place a bit of Vaseline at the rudder hilt where it will not pass through the tape.  Install the shoe and dry install the servo platform with the rudder in between. Make a dam that will hold the resin around the sleeve and hull area. Pour in thickened resin to your liking and allow to cure. Remove the shoe and rudder to remove the tape.

  

"Hey Vern, we're outta the rudder shop, let's go to the movies."