Having built a previous steerable nose wheel airplane, I am aware that any stiffness in the nose gear/ nose gear linkage will also affect stiffness in controlling the rudder when in flight as the rudder and steerable nose wheel are part of the same system. When building and installing my nose gear on my 601 kit this past weekend I found that it operated very stiffly (without the bungee attached). I disassembled, polished the nose gear shaft, gently ground the connecting surfaces of the upper and lower bearings, re-lubricated and now the nose gear moves with much less resistance. However, when I attached the bungee, now the nose gear moves with great resistance. Wouldn't this translate to stiff rudder controls when in flight because when in flight there would be no weight on the nose wheel same as now and any stiffness now would be present in flight? Hey, I'm just asking because I don't know any better. I would appreciate some help, this is my first message. thanks Charles Thie, Burlington, Iowa.
Nose gear is off the ground. Have not installed pedal linkage and am turning the nose gear by hand. Never the less, it turns easy with the bungee not attached and turns hard with bungee attached. To me, this would translate to needlessly hard rudder pedal control. Again, I do not hold myself out to be an expert. But from building and flying another stearable nose wheel plane, any friction on the nose gear translates to hard pedal situation in flight to control rudder. Maybe when I get the plane ready to go and fast taxi, I will find that the pedals/rudder are not stiff due to this but I have my doubts at this time. Sincerely, C Thie, Burlington, Iowa
Charles - I just finished my 701 and I am now flying. I spring loaded my rudder pedals and it works great. You put a spring if front of and in back of the point at which you attach the rudder pedal to the steering rods. That attachment is an "Aurora Bearing" as found at Aircraft Spruce. Your steering rod goes through the bearing with a spring on each side of the bearing held with with either a nyloc nut or a castle nut with cotter pin and some washers. Think about it a little while. It gives you enough travel while in flight to turn the rudder without fighting against that nose wheel and you can still have the steerable nose wheel on the gound. I got the idea from Larry Martin a builder on the Zenith website. - Chris
I've asked the same question. I found the 'mod' you refer to. What springs are you using? They will have to be fairly strong as they will have to resist the rudder cable tension in the backward direction. I guess you also made some new metal rods. My aircraft is the 601XL but the steering sounds similar.
Paul - I used some springs from "Grainger". I would have to measure them but I believe the ID of the spring was 9/16" and they were apporximately 2" long. I"ll get the exact measurements. Your right I did have to make some new rods and one is longer than the other. If you spring load the rudder pedals you don't have any tension to worry about. They will relax when not in use. I set my rudder pedals according to how comfortable I would feel in flight and tided the turnbuckles right there. The tension does not mean alot because when you fly and put your feet on the rudder pedals whatever one you push the other has tension also. So going back to my previous statement. When your not flying or taxiing your rudder cables will relax and have slack in them. This does not happen however when you build to print specs. Then your rudder cables have constant tension and every push of the pedal means a push of the wheel. I hope I'm explaining this correctly; I don't know if I'm getting my point across. - Chris
The bungee will "force" the nose gear tube into the nylon "V" block, if your motor is not hanging there yet when on the ground there is greater resistance to turning because the tube has to be raised out of the "V" and over come to twist of the bungee to turn. In flight the nose gear rests in the "V" to keep the nose wheel from flopping around in the wind, and in my CH601HD there is no need to apply rudder pedal in cruise flight, only to co-ordinate turns in the circuit pattern. Flies "feet off" like my C-172 did.
After a 100 or so hours the suspension will soften and the turn effort reduce as things wear fit.
I fought with this same problem. Finally after having taken the bungee on and off so many times, I damaged the outer cord. I purchased a new bungee from Zenith and all my problems were gone. I then compaired bungees and the new one was about one inch bigger in circumference. I concluded the one supplied in the Kit was undersized.
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