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I have a question if anyone can answer. I just installed the rudder pedals and put in the kit supplied cables. I realize that even after the new modifications I will have to modify the bulkheads some more. I have sort of two questions the first one is the plans state that you need to bring the rudder to the left full stop while the pedal is vertical and then measure for the attachment. Then you are supposed to have the rudder neutral and the right pedal vertical to measure for second attachment. It seems to me that the rudder and and the pedals should both be neutral when you apply tension to attach. Am I wrong wouldn't it be awkward the way sonex has it on the plan procedures?

Second question is that the cable does not fit into the A223 pulley slot so it even falls outside the pulleys and occasionally gets stuck outside of pulley this obviously isn't ok. Should I somehow modify the pulley grooves to fit?

Hi.
As to your first problem/concern ,I have a nose dragger and I assume your talking about a tail dragger so I can't help you there but as to the cable not fitting in the groove of the pulley i am a bit confused.
You state that the cable does not fit into the A223 pulley slot which doesn't make sense if you are using the cable supplied.It should fit the groove perfectly.
No matter what you do i would not modify the pulley groove in any way.Once the tension is put on the cables they should not fall out of the grooves.If you have proper tension and the cables are still coming off the pulleys it can only be a way out alignment which would mean something is out of place from the plans.
Pictures would help.
Good luck,
Mike

The A-223 pulleys are supposed to fit cable sizes from 1/16 to 1/8 inch, and the rudder cable supplied in the Onex kit (at least the one in mine) is 1/8 inch and fits nicely in the pulley groove. The problem with the cable coming out of the grove might be caused by misalignment of the pulley. Sonex, as I recall, specifies that the plane of the pulley should align with the plane formed by the entering and exiting cable segments to within 7 degrees. Zero degrees is better, as it will pretty much eliminate wear on the pulley groove. I'd recommend checking all your pulley alignments. Also, as a safety precaution, all pulleys should be fitted with cable guards. These can be purchased but are quite simple to fabricate. Here is a photo of a guard mounted to one side of the pulley block. There is about 1/32-inch clearance between the guard and the rim of the pulley.

Regarding the rudder pedal rigging: The procedure that Sonex prescribes for this works pretty well with one big exceptions. If you elect to move the rudder pedals aft (to accommodate a shorter pilot), this with change the angle at which the cable and cable adjuster meet the pedal. The result is that you will run out of rudder travel at the point when the cable begins to pull radially on the pedal, that is, in the full pedal-aft position. This will occur before the rudder hits the stops. The only solution to this appears to be to move those first two pulleys aft by the same amount as you moved the rudder pedals. This will keep the angle the same, and the rigging procedure will still work.
Regarding the springs, the ones in my kit proved to be way too large. I ended up using Hillman #25 extension springs (OD 13/32 in, length 2 3/4, wire size 0.041 in, zinc plated). They seem to work well.

Thanks Don, I hadn't even considered the cable stops and I will certainly fabricate those. I'm still confused about rudder rigging procedure and guess I misunderstood instructions but I'll contact Sonex to clarify. It just seems to me that if ur full left stop for initial l side rigging and then full neutral on pedal and rudder for right side then not only will left cable adjuster be much shorter than the right cable adjuster but when pedals are neutral u will actually be at full left rudder. That just doesn't seem right but I'm sure I'm just not seeing it right.

Vegaj02 wrote: It just seems to me that if ur full left stop for initial l side rigging and then full neutral on pedal and rudder for right side then not only will left cable adjuster be much shorter than the right cable adjuster but when pedals are neutral u will actually be at full left rudder. That just doesn't seem right but I'm sure I'm just not seeing it right.

I'm pretty sure the procedure is designed both to center the rudder and remove any slack in the cables. First you set full left stop, then set everything neutral when marking the right side. So, rudder pedals centered should mean rudder centered, and the right stop comes automatically. Even reading what you just wrote suggests this is correct ("full neutral on pedal and rudder"). One adjuster will indeed be shorter than the other, but this is mostly because the rudder pedals are mounted one in front of the other, such that the point at which the rudder cable adjusters attach to the rudder pedals isn't actually the same distance from the firewall when the bottom of the pedals are even. I believe the attachment points are offset by a good inch.

The instructions do seem a bit counter-intuitive but I followed them to the letter and it came out great. When I marked/drilled my holes in the adjusters I erred about 1/8" closer to the pedal on both sides to be sure I was getting some tension into the cables once mounted and prevent the pedals from bottoming out on the firewall when I press the pedal hard. I also shortened the provided springs by a fair bit to get a nice positive return on the pedals (to keep the cables from going slack.)

(note: I'm assuming that the rudder rigging directions for the Onex would be the same as for a Sonex/Waiex.)

I think we are talking past each other just a tad regarding the alignment process. But bottom line is that whatever alignment method is used, when the left pedal is straight up and down, the rudder should end up against the stop at full left deflection. When the right pedal is straight up and down, the rudder should be up against the stop at full right deflection. When the rudder is in the neutral position, the pedals should both be sloped slightly aft at the same angle. On my project, this did not require separate geometries for the two cable adjusters. They are identical and are attached to the pedals at the same point. Here's a photo of my right rudder pedal in the neutral position. Note that I chose the option to set both pedals aft by 2 inches. The geometry should be the same regardless of where you elect to locate the pedals.

Don P. I appreciate you posting the picture of your cable adjuster set up to the rudder it really helped me see the big picture. I had to take a couple of months off from the build but its finally time to get cracking again and will continue with the rudder set up since I am pretty much ready to install the gas tank, glare shield and the engine is actually on the firewall already.

Since taking the picture in my post of 12/28/15, I elected to replace the rudder-return springs with something a little more substantial. I'm now using two Serv-A-Lite #51U springs. This company was bought out by The Hillman Group a while back, so the springs may go by a different model number. They measure 3 7/8 inches long, 9/16 inches in diameter, and are made of 0.62 inch wire.