David_Moen

Hmmm....with a 3" tiller bar on the rudder servo, the slots in the fuse need to be extended forward a bit so that the cables don't rub.

drbebob

I used a tiller bar made out of the largest heavy duty Hitec double arm; which is a bit under 3" hole to hole. You might want to consider drilling some holes inboard of present ones.
I had to relieve the rear edge of the exit slot a bit.
I used Pacer hinge glue but Gorilla glue works also. Put a good wad of glue in the hole and a light coat on the hinge and then rotate the hinge into the hole to spread it evenly along the length of the hole.

Bob

Wings-RCU

My Feedback: (2)

David, Did you run your cables straight back or cross your cables?

David_Moen

I ran them straight back using an Airwild 3" tiller. The aluminum control horns need to be shortened a bit to get the spacing right out at the rudder end of things. I'm assuming we want a perfect rectangle here, with the distance being equal between the holes in the tiller bar and the holes in the control arms on the rudder. If using the Dubro kit, the plastic arms that thread onto the control arm need to be re-drilled and shortened a bit.

A productive day yesterday, I got the elevators and rudder glued up, linkages made up and installed, pull-pull installed and hinge gaps sealed. I can easily get the wings ready today and put the fuel system together.

One thing I'm scratching my head about is venting the fuse. Because I'm going to have a canister inside he fuse, I want to open up the covering on the bottom of the fuse. just aft of the fudder servo there is a spot between two formers that would be perfect, but I dont want to just make a big hole in the covering, I would like to make a louvered panel that I can cover the area with after I cut away the covering. Has anyone seen such a thing or have any idea of how I could make it?

JoeAirPort

My Feedback: (41)

Yep I am experiencing the same issue. I need to have my work's machine shop shave a 1/4 inch off the aluminum cones that thread on the rod. Otherwise there's no way to get the 3 inch spacing between cables on the rudder side. Also I need to cut those black plastic pieces down to one inch and redrill them. My distance from the center of the hard poiunt to the hing line is 7/8". And it really cuts your rudder deflection if you don't cut them down. Dave how long did you cut them? Or how far from the threaded rod is your new hole drilled?

Wings-RCU

My Feedback: (2)

I thing you need to cross the wires so the exits are in the right place.

drbebob

Crossing the cables may be of some help but not totally necessary. I did not use the "cones" from Dubro and just used an 8-32 bolt glued in. I put 5 more flights on my Edge today and flew several knife edge loops. The bolt did not bend so who need the aluminum weights on the rudder horn.

Bob

JoeAirPort

My Feedback: (41)

That's a good point. Those aluminum cones may be needed to support the 8-32 bolt on 40%'rs but not on this BME Edge.

David_Moen

I just used my grinder and buzzed 1/8" or so off the tip of each of the "cones" no machine shop required! I installed the threaded rod and measured out to the hinge line, then I drilled a hole in each arm right on the hingle line and zipped the excess off with my Dremel. then I rounded the ends of the control arm off..can't tell it wasn't made that way in the first place. I measured between the holes on the controll arms to make sure that the disstance between the holes was 3" and that each hole was exactly 1 1/2" from the hinge line. When I had that all perfect I glued in the hinges.

I set up my radio for dual elevators and plugged the servos into my RX and a 4.8V battery. Holy Cow! The 5955 is FAST even at 4.8V!

JoeAirPort

My Feedback: (41)

It might help clear the slots but without using an offset servo arm you will get more slack on the non-pulling cable. See SWB's website for examples.

http://www.swbmfg.com/rudex.html

David_Moen

I saw that...my set up is the top setup, a perfect rectangle. There is only the tiniest bit of slack in the non-pulling side and there is no slop whatsoever in the rudder travel, at netral, the servo is quiet, but if I apply a very small bit of force to the end of the rudder, I the servo starts applying counter-force instantly with no actual movement of the rudder...very cool!

drbebob

Exactly

drbebob

David-- If you are using a tiller bar one advantage of same is to crank up the tension on your cables; then you will have only inconsequential decrease in tension of the non-pulling side. My cables actually have a musical resonance when I pluck them though I haven't measured the pitch of the tone.

Bob

JoeAirPort

My Feedback: (41)

BTW I remember you said that you are using the rocket city RCL70 on the elevators and ailerons. Does this horn let you put the clevis pin on the hinge line? On the Nelson site there are not dimensions for that. I prefer the Nelson over Dubro but the Nelson offsets are shorter. My Edge II distance from hard point center to the hinge line is 3/4 inch.

Edit: I just called my LHS and they measured it for me. It's 3/8 inch so I guess there will be some aileron differential right?

drbebob

The hard points are very beefy so I fudged a bit and drilled about half the radius of the dowel toward the LE of the aileron.

Bob

JoeAirPort

My Feedback: (41)

That works. Thanks, I'll probably do the same. Actually I meant to do that on my rudder horn and forgot to drill the hole a little further back in the hard point....I think I'm getting old.

drbebob

I almost remember when I thought I was getting old too.

bob

David_Moen

I actually found that with the longest arms that are in the box with the 5945s, and perfect linkage geometry, the holes for my aileron control arms are going to miss the hard-points! I will be just inbord of both hard-points. Also, after some very carefull measuring, it seems that the hard-points in each aileron are in slightly different locations. THe hard-points seem to be sunk into a big block of balsa, I can drill the holes where they need to be and wick a bunch of CA into them to harden the balsa (the hard points will end op getting sandwiched between the control horn and the backing washer) or I can locate the control horns on the hard point and have slightly less than perfect geometry. WHat would you do?

drbebob

Since the servo arm travels in a horizontal arc there is no such thing as perfect geometry in this scenario. If the servo arms traveled in a vertical arc as in the DP aircraft then you can get pretty close . I went with the incorrectly placed hard points and adjusted the feel of the surfaces using expo on the TX. In my Yak that I am building ARC I am drilling out all the hard points except rudder possibly and placing them so that when the servo is at maximum travel points the servo linkage is perpendicular to the hinge line thereby giving maximum mechanical efficiency at the maximum throw points (where it is needed).

Bob

David_Moen

Bob,

On your Yak, is the aileron hard-point installed in a block of balsa? If it is, given that my control horns will be squeezing the hard-point, I think that hardening the surrounding balsa with thin CA will give me sufficient strength and durability.

JoeAirPort

My Feedback: (41)

Even though the mechanical advantage is not optimal at each end of deflection when your clevis pins are not on the hard points, you can change the length of your control rod to get the throws equal up and down. The only thing is you'd have to reprogram the servo centers and endpoints or use a matchbox. I will try to get the Nelson control horn pin as close to the hing line as possible but I will probably be a little short. I'm using the Hitec 5945's so I will do as I explained above: Adjust the control rod for equal throws, adjust the control horn height to match the throws on both ailerons, then I will reprogram the centers and endpoints on the Hitec programmer. I use these little paper protractors on my servos and control surfaces. Done it before and it works great.

drbebob

I haven't put the hard points in yet; but they will probably have end grain balsa hardened with thin CA supporting them as you mentioned.

Bob

David_Moen

I moved my aileron control horns to where they were supposed to be, rather than where I thought they should be! With this arrangement, using the longest servo arms that come with the 5945s, the control horns sit outboard of the ends of the servo arms substantially. I think I'll get some longer arms, this will square things up geometry-wise and give me more surface travel as well. What length of servo arms is everyone using on ailerons and elevators?

coony2787

My Feedback: (33)

Has anybody recieved the new tail wheel bracket yet? Max said he was sending everyone that a plane a new one. I have yet to see mine. My original tail wheel lasted 2 flights

Chad

JoeAirPort

My Feedback: (41)

When I put a square on the aileron hinge line and measured the distance from the hard point center the servo center, I got exactly 1 1/4 inch. I ordered the SWB 1 1/4 arms for the ailerons and elevators. I will make sure my Nelson control horn heights are 1 1/4 inches from the hinge and that way I will get very close top 50 degree surface deflection with the servos and a 1:1 mechanical advantage. I hope this all works out but that's the plan. I still have to hing those surfaces so it's not done yet.