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The plans called for a 54" wheel mounted on a standard Edson pedestal with chain/cable to a radial quadrant on the rudder stock. The requirements were that the wheel make 1 1/2" turns lock to lock and wheel pressure not more than about 20 pounds. I sent all the measurements off to Edson for a quote. Guess what? Edson does not discount very much to anyone. Even if you are buying the complete system. Their quote was a bit over $3,500 for a basic system. If I wanted the fancy system with carbon wheel and rope drum steerer, the price went up to about $7,000!
 I had pretty well resigned myself to a plain Jane steel wheel when a couple of threads in rec.boats.building and rec.boats.cruising got me thinking. I blame all of this on Evan Gatehouse, a designer at Farr International, who participates in both news groups. Actually, all he did at first was point out that a composite radial would not be all that hard to make but that got my imagination cooking and I suddenly realized that none of this is rocket science. I have all the tools I need and Edson had already calculated the maximum rudder torque so the rest was simple ratio problems. Why not build the whole thing myself?
Bronze was out as my furnace can't handle enough at one time to cast most of the parts and my lathe can only swing 10". Composites and engineered high tech plastics were the logical choice. Modern plastics are strong enough for the loads, easy to fabricate and machine, don't rust or corrode and it is light weight. With a little help from the DuPont engineers, I settled on Delrin and Torlon for the parts that are not FRP composites.
THE RADIAL QUADRANT
 I started with the radial. The first step was to build a mold. The radial is symmetrical top and bottom and side to side so a single half mold could be used twice and the top and bottom bonded together. I mounted the PC690 router on a bar with a block to act as a pivot and routed a 19" hole in a 24" square piece of 3/4" MDF. Then using a round over and a cove bit, routed an Ogee into the edge. I then drilled a small hole in the center of another 24" square piece of MDF and epoxied the hole to it. Shaping the inset for the ropes took a little more work but that was done with a template to insure it was symmetrical. The next problem was to insure that the hub was exactly perpendicular to the plane of the radial. The rudder stock diameter will be 120 mm so I glued together 3 pieces of MDF and turned them to 120.3 mm on the lathe. This cylinder was mounted to the mold with a long screw. The hub had to have a break so that it can be clamped to the rudder stock so a piece of 1/8" UHMW was fitted into a slot on the cylinder. A couple of coats of epoxy the seal it all, several coats of wax and a couple of coats of PVA and I was ready to start the layup.
 Having no idea how strong to make the radial I decided that gorilla engineering was the best approach. I had plenty of scraps of fiberglass in several patterns and weights so material cost was not a problem. I started with a circle of DB180 biaxial cloth and then wrapped 2" wide strips of unidirectional around the hub and out to the edge in a radial pattern figuring that would take the torque load. Then another layer of biaxial and more 2" strips this time run straight in from the edge and lapping up the hub. Another layer of biaxial and more strips of uni running around the circle for good luck and topped off with a final layer of biaxial. Total thickness, about 3/4" around the hub and 3/16" at the rim.
The end result is a very strong and light weight custom radial that would have cost close to $1,000 from a professional fabricator. It still needs some reinforcements for the autopilot boss, lashing points for the cables and drilling for the hub clamps but the total cost was about $30 for the MDF and the epoxy. Only had one problem. That much glass releases a lot of excess resin when you bag it. I thought I had plenty of breather under the port to absorb it but I ended up sucking epoxy into the port, up the hose and into the quick connect. $40 worth of fitting s ruined! I will have to find a time when Marilyn is out of the house for a few hours so I can bake them out in the oven and still have time to air out the house..
THE DRUM STEERER
The steerer took a little more thought and effort. This is a rope drum steerer like the ones used on the big high performance race boats. It is basically a drum with a spiral cut into it to guide 3 or 4 turns of 8 mm T-900 low stretch line mounted in a body that mounts to the pedestal. A break plate mounted on a pair of studs in the end of the drum is drawn against the body by a 1/2" stainless rod with an Acme threaded end running out through the center of the wheel. I already had a chunk of 6" round Delrin (acetyl) that I could mill the body from and have plenty left over for sheaves and other parts and found a foot of 4" round on E-bay for $30. The major cost was $100 for 12' of 1/4" Torlon rod that I cut into 1" roller bearings.
Boring the body was fairly straight forward. Delrin cuts like butter but the tool has to be very sharp to make a smooth surface. The only scary part was cutting the bearing surface way up close to the chuck where you can't see it and you can't get a hole gauge out past the bearing stops. You can't see what has happened until you remove the piece from the lathe. All I could do was trust the cross slide dials and stops on the ways. Fortunately, I had tuned up the old 10K a few weeks ago and made sure everything was tight so it came out only .002 over size. Good enough for plastic rollers
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The real problem was cutting a 2.25 TPI thread in the center of the roller drum with a shoulder at each end. It took some experimenting to find a gear combination but even with the lowest back gear speed there was no way to start or stop the spindle in time to avoid chopping into the shoulders. My solution was to freewheel the spindle and drive the lathe with a wrench on the lead screw nut. It worked but cutting a 1/2" deep thread .010" at a time required a lot of wrench turning.
A test fitting of all the parts gave me confidence that I had not wasted the weekend. It rolls easily and quietly. Not bad for $150 considering that Edson would want $1,600 for a Drumroll steerer.
After all that, turning the sheaves to guide the steering lines was a piece of cake. One question I had about the steering sheaves was how to mount them so that they could be aligned with the run of the steering lines.
 I decided that as it was a custom fit, it did not need to be adjustable the way an Edson unit would be. So back to the Autocad drawings and place the lower sheaves in the exact position. Then measured the angles required for the steering lines to cross and meet the drum at a tangent. The bracket was made up from some 1/4" x2" 316 stainless flat stock. I cut a couple of angle blocks from some maple scrap to hold the sheave cheeks in position while welding them on. About 5 minutes with the MIG welder and they were almost spot on but I am known for producing "gorilla welds". (Strong but ugly). It took half a day with the angle grinder and Dremel to get them looking decent and another hour on the buffing wheel to make it shiny. Don't know why I spent all that time making it look nice. It will be mounted on the engine compartment ceiling where nobody can see it.
THE WHEEL
All of this high performance steering gear deserves a high tech wheel. RUTU's cockpit is wide so the wheel needs to be about 54" in diameter so it can be reached comfortably from the windward side. A 54" carbon fiber wheel like those on the Open 60s and big Farr designs cost thousands of dollars but now that I have built all this other equipment, why stop now? A true round rim in steel would be far beyond anything I could form but a mold for a composite wheel would be fairly simple. The problem was what to do about spokes. Another r.b.c member suggested a great idea, golf club shafts! I immediately went by the Club Doctor and asked if they had any shafts that had lost their heads and were unrepairable. They presented me with about a dozen clubs for free. Six of them are Ping 350 series stiff flex driver shafts. They are every bit as strong as steel and even a bit stiffer. Best of all they have a nice taper that will give the wheel a high tech style. I was told to come back in a week or two and they would have enough Ping 350 shafts for all the spokes.
 The mold was routed out from a sheet of 3/4" MDF with extra layers of MDF around the outer rim to build up a thickness of 2 1/4". Once assembled with bolts so it could be easily removed, I trued out the roundness with another pass of the router. Then I routed a shape into the edge with a 1 /14" bowl and tray bit and widened it by another 1/8" to make a shoulder just above the cove for the outer mold to rest on. The outer mold will be some 3/4"x1 1/2" UHMW strips that I had used as cauls on the deck beam clamping jig. I routed the same shape into them with the bowl and tray bit. This will give the wheel a cross section of 5/8"x1 /1'4" with 1/4" radius rounded over edges. I tested the shape in my hand by routing a sample out of wood. It is very comfortable.
The lay-up began with 4 layers of 2" carbon tape wound into the groove. Then some carbon tow to fill in the corners. The question arose as to what to use as a core. Obviously, solid carbon would be unnecessarily heavy and expensive. Several e-mails back and forth to Evan Gatehouse resulted in an idea to use latex surgical tubing. I would feed the hose through a small hole through the inside surface of the mold and wrap it around the groove. After the top tows, 4 layers of carbon tape are laid and the outer mold clamped in place, the plan was to simply hook the tube to the air compressor and inflate it. That would push all the fiber out against the mold leaving a uniform cavity in the center. I could also slip some 12K carbon braid over the tubing before it is placed giving the rim some diagonal reinforcement on the inside!. BAD IDEA!
When surgical tubing inflates, it expands length wise as much as sideways. As it inflated it pushed the braid along and quickly ended up looking like a boa constrictor digesting several meals at once. The result was a very high tech Hula Hoop with a lumpy outer surface.
For the second try, I made up a long skinny tube from vacuum bagging film and tape. I also found that to hold the UHMW outer mold in place and make sure rim was an even thickness and the outer surface was a true circle I needed to add more clamps and a layer if steel banding to the mold. Rather than struggling with C clamps, I made up special fittings from angle iron and threaded rod. This time it worked great.
The hub required some more imagineering. It had to be about 6" in diameter, 4" thick, light, strong and black. The ideal material would be epoxy with chopped carbon fiber but casting epoxy in thick sections is a problem because of the heat. That called for a metal mold so that it would be easier to remove the heat. A smooth wall coffee can was pressed into service. I cut out the bottom and then hacksawed it to a bit over 4" long. The top and bottom of the mold was cut from a scrap of 1/4" aluminum plate. I mounted the plates on the lathe and cut a groove for the edges of the can to fit in and drilled a hole in the center. I wanted the hub to be hollow so that the break knob would fit inside. The dimension of the recess was determined from the diameter of an empty brazing flux container. The whole thing was held together with a bolt through the center.
Using the slowest hardener and resin combination I had I proceeded to mix the epoxy. Having never worked with chopped carbon, I was not prepared for what happened next. The instant the carbon was added, my nice benign epoxy became a black stringy mass. It climbed the mixing stick. It crawled up the sides of the pot. It gulped air like a drowning man struggling for his last breath. I saw a disaster in the making but, like Jason battling the Hydra. with much pushing and prodding and bashing to force out the bubbles I managed to stuff the writhing mess into the mold. I pushed the flux jar in place and bolted on the top plate and sat back to wait. There was considerable epoxy on the outside of the mold so I wiped it off but after a time more appeared. Then even more. The mold was getting warm expanding the remaining trapped air and squeezing out the epoxy! It was beginning to look like that pot of Flubber that Fred McMurray battled. The next hour was a constant battle for ice. I used up all of ours and borrowed from the neighbors. The mold finally calmed down and later that evening I stripped the mold and found a very solid and light weight hub. After all the excitement, it was a simple matter to touch the hub up on the lathe and then set up on the rotary table to mill sockets for the spokes.
To insure concentric positioning, I used the mold as the clamping jig. The hub was mounted on the mold axle and the rim mounted on stepped blocks screwed outside. The carbon braid was threaded onto the spokes and covered with poly. Then short lengths of heat shrink tube were slipped on. (The pink things in the picture)
The spokes were epoxied into holes drilled into the rim and 50K carbon tow was lapped over the joint. I slipped the heat shrink over the wet tow and shrank it down to press the tow. Then I wrapped the rim with some heat shrink tape that I found on a kite making site. The result was a very smooth ant strong joint.
PEDESTAL & SLOT
Flush with victory, I figured why stop there? No need to pay anyone for a custom pedestal to fit the steerer and wheel, I decided to build one similar to the Edson and Whitlock type with the instrument pod on top. I built the female mold for the base directly from MDF but the instrument pod required a plug. As these molds would be hard to vacuum bag, I swallowed my epoxy pride and ordered a couple of gallons of polyester and gel coat.
 To insure that the pedestal would be very ridged, I sort of over did the glass. It is thick enough to make a pretty decent dinghy hull.
I have to say that the pedestal came out rather nice but the instrument pod took a couple of tries to get just right. .
The slot that the bottom of the wheel fits in worked out great. It is vacuum bagged in epoxy and has a drain fitting to accommodate a 1" hose. As an after thought, I added a small fitting to accept the outflow of the engine cooling water anti syphon so that it will not end up on the cockpit floor.
Here is a trial set up of the pedestal, wheel and slot that I assembled just to make sure everything fit.
 I will cut a piece of 1/4" Starboard to cover the access hole and the whole thing will be painted in Awlgrip to match the hull. There is also an aluminum plate epoxied to the bottom of the pedestal so that it can be through bolted to the cockpit floor with no fasteners showing. Electrical and instrument cables will run through conduit in the corners of the pedestal and the RL70RC will mount on a guard rail over the Ritchie Globemaster compass. The instrument pod will hold the A/P head, Nexus Multi and Nexus Wind displays and there will be a Kobelt engine control on the starboard side.
The whole project ended up costing $435. Mostly in carbon fiber and epoxy. And I used up most of the fiberglass scrap that was to small for anything else. That is about $8,000 less than the bid I got from Edson. Overall, a pretty good months work.
BTW, as you can see I am up to my kiester in Spade Anchors if anyone is looking for one.
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