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Friday, March 4, 2016

Miscellaneous Build And Set Up Tricks

Today's ARFs are better than they have ever been. In fact, they are really even better than what we used to build from wood kits by hand. They are easier than ever to assemble, but there are plenty of things you still absolutely have to get right.

Over the years I have written about all of these things, but now I want to compile all of them so they are easy to find, and that's what this article is all about.

One of the things I can't teach you is patience. I am probably the least patient person on the planet, but over the years I have learned to slow down and get things right the first time. Some people brag they can build a plane in an hour or two, but then again, some of those planes constantly have things falling off of them, or they generally don't fly very well. To build the best plane you possibly can, you have to take the time to get it right. Otherwise, that is wasted time because you just have to do it over. On things like getting the tail on straight or the hinges in properly, you only get one shot at it, so you have to be especially careful here. If you get the spinner gap wrong that won't hurt anything but the appearance, but if the tail is on cooked the plane won't fly straight.

So in short, take your time and simply enjoy the process. Get everything as right as you know how to do it and you will be rewarded with a good flying plane.

Also, details count. Small things like making the pushrods operate smoothly with no play or slop is more important than you can imagine, as well as sealing your hinge gap. There are a lot of little things to look out for, but I will try to cover them all, so this article will probably never be finished. I will just keep adding to it as we go, so save this link and check it often. It would probably also be helpful to subscribe to my blog.

Before we get started, a big thanks to Thunder Power, 3D Hobby Shop, and Extreme Flight for their undying friendship and support. Everything I do, including these articles would otherwise be impossible. These companies have been with us literally from the beginning and it's all sort of one big family for me.

Also thanks to my friends at Hitec who help out with excellent service, plus servos when I can't afford them. I will probably try an excellent Hitec radio in the near future when I get all my projects caught up and can do the radio the justice it deserves.

Also  Click To Enlarge On All Pictures In This Article.

Take a deep breath............ and here we go.


I always plan to take lots of pictures and do a bit of a build thread, but then I always get engrossed in the process and forget. This time I am going to show you how I install the horizontal stabilizer (if I remember to take the pictures, that is). I have to explain this on RCG every so often and it's not easy to do without photos.

The first thing I do is glue the hinges into the control surfaces (We will cover that in a later update) and after those are dry I trial fit the elevator to the stab.  I make sure the hinges line up and slide all the way in, and this is much easier to do before the stab is in the plane. I set the elevator aside for now and final hinge them after the stab is glued into the fuse.

Then it's time to put the stab in. I put the wings on the plane and slide the stab in, then measure it side to side to make sure it is reasonably close to centered. I'll come back and get it dead on after I check to make sure the wing and stab are parallel to each other. I hold the plane up with a solid color wall behind it because with a solid color there are no distractions in your vision that can cause an optical illusion. With nothing else in the field of view it's much easier to see if the alignment is correct or not.

Here I sight down the top of the wing (one eye closed helps) to make sure the stab sits parallel to the wing. I have only had one or two EXPs be off here, and most times it is just a matter of lightly sanding the bottom of the high side of the saddle a little until the stab sits level. If it takes more than one or two passes with an Emory board then I will cut a piece of business card about 1/8 wide and slide it under the low stab. I have never had one any further out that that, and even that much is extremely rare.

Now I measure the stab side to side again, only this time I get it dead on. I also eyeball it to get it as square with the wing as I can, but I will measure it later.  From here I jam a long hat pin all the way through the rudder post (see photo) and into the back of the stab. This locks the stab in so it cannot move side to side when I square the stab to the wing. Once the pin is in, I measure again to be sure.

From here I measure from the wingtip to the stab tip, and adjust the stab as necessary to get the measurement the same on both sides. I check my side to side measurement one final time and then check the wing tip to stab tip over and over until I am satisfied it is dead on. Once that is done I hold the plane up to the wall again and make sure the stab is still parallel to the wing.

I absolutely torment myself getting this as perfect as I can possibly get it. This part and getting the hinges right are the most crucial part of the build.  If you screw it up the plane is not going to fly right. Certainly you can get away with it being off a little, but nothing flies as good as a dead straight airframe. Everything else is either easy to redo or live with. If you mess up the cowl spacing it's not going to make the plane fly badly, but getting the tail crooked will.

Once I am absolutely dead solid sure the wing and stab are parallel, the stab is centered in the fuse, and also square with the wing, Check this as many times s you have to in order to be absolutely dead solid sure you have it as perfect as you can get it. The more perfect you get this part, the better the plane is going to fly.

Remember, you get as many chances as you need to get it measured perfectly, but you only get one chance to glue it in. If you get it really of, you may have to use debond and pull the whole thing out, but that's a nasty messy job and it's much easier to take your time and get it right before you glue it.

I like to put the fuselage in my handy Ernst plane stand and tilt the plane so gravity will help the CA run into the joint. You don't want so much tilt that the CA runs out the other side (and all over the plane), so only a few degrees of tilt it necessary.

I run a bead of thin CA into the top of one side where the fuselage and stab meet. I let that set up for about a minute and then pull the wings, set the fuse aside and find something else to work on for about 10 minutes. Then I do the other side, wait 10 minutes and wait for it to set up. Then, I flip it over and repeat the process on the bottom of the stab.

After about an hour all the CA has set up and it's safe to handle the plane. I pull the pin out cut out the rudder post behind the elevator. I forgot to take a picture of that, so here's one of my Yak. I cut the post out with a hobby razor saw that makes nice clean cuts, and all I do from there is seal the edges back down with a trim iron. If you are really picky you can cover the expose wood behind the stab, or even brush on some hobby paint or dope.


I've been using cyanoacrylate hinges since the late 70s, so I have developed a pretty good technique. I also have had a lot of great builders show me their method, though technique is hard to teach and you will develop your own anyway.

The first thing I do is use a trim iron to tighten any loose covering and eliminate any bubbles on the trailing edge of the flying surface and the leading edges of the control surfaces. Loose covering and bubbles can interfere with smooth operation, so they have to go. You can use a covering iron, but a trim iron is so much easier to work with.

Before you start gluing, you need good glue and good tools. I like Zap brand CA for a lot of reasons but especially because of their slip on applicator tips. You  can control the flow and put it exactly where you want it. Also, have some Golden West Super Solvent handy to clean up any spills.

Click To Enlarge On All Pictures

Then I fit the hinges to the control control surface. On most 3DHS planes the hinges are already glued into the control surfaces, so if you are building one of those, skip this part.

On EXPs, the slots are already cut, so I slide the hinge into the slot and get it centered and straight. To make sure you have the hinge the right depth, it's helpful to hold another hinge up to it and that makes it easier to set by eyeball.

Then, I then run a bead of CA along the hinge where it meets the control surface and watch it wick in. It helps to use a tip on your CA bottle so you can control the flow, and for that I like Zap CA and their glue tips. On the left you can see how the applicator allows pinpoint accuracyy, and on the right you can see the bead of CA laid down.

When I glue the hinge, I hold the control surface so that gravity helps the CA run into the slot. The important part is to run the bead and make sure all of the CA wicks in. You can run a bead on both sides of the hinge and it will be locked in forever. Again, the important part is to see the CA run in so you know you have enough glue in the slot. Let the control surfaces set up and dry for a few minutes and take a break, or tinker with another small job like setting up the tail wheel assembly.

Once that's cured, trial fit all the control surfaces on to their appropriate flying surface. Sometimes the slots don't line up perfectly so you will have to run a #11 Xacto knife into the slot to open it so the hinge slides in.

For good 3D you want the surface to have as much movement as you can get, but that usually also gives you a large gap between the flying and control surfaces. This gap can really denigrate your planes responsiveness and even potentially set up deadly high speed flutter. To avoid this we try to keep a good, tight gap.

The technique is the same for all surfaces, so I will describe how I hinge the ailerons. First I slide the aileron onto the wing and the hinges into the slots. Then I check to make sure the aileron doesn't rub on the SFG or the inner part of the wing. I make sure I get full movement in both directions.

Since I want full throws and a tight gap, I deflect the aileron until it's leading edge (LE) bevel is touching the bevel on the trailing edge (TE) of the wing. Basically, that's all it's got. The important part now is to make sure you have the hinge pushed as deeply into the back of the wing as you can get it, and that's to assure a small gap.

So, you fully deflect and push the two surfaces together at the same time. It is tricky to get both a tight gap and full deflection, and then glue it on top of that. Remember that you want to stand the wing up on it's LE edge so that gravity will help the glue run into the slot, and all of this is tricky when you are trying to deflect the surface, push them together, and glue them all at the same time.

You almost need three hands, so if you can have the wife or friend hold the wing that's very helpful. For hinging the tail I hold the fuselage between my knees.

I start with the outer hinge and use a solitary drop, all while deflecting and pushing the two surfaces together. Then I do the innermost hinge. If I am happy with the movement and the gap, I repeat on the other two hinges. I only use one drop so I can get it apart with debond if I screw it up. Once I am happy the gap and movement are good, I go back, deflect the surface and run a bead of CA along the hinge. Again, it is important to watch it wick in. If you want to be especially careful, you can glue both sides.

That is pretty much all there is to it. Worth noting is that the standard hinges work fine, but I was a fan of Radio South Pro-Hinges, standard hinges from the beginning. Even the Boss will tell you they are the best. Since I learned how to hinge with Radio South hinges, I continue to use them 35 years later and will probably never change.
I have done so many of these that I know in advance exactly what I have to do. I have also acquired  a nice spare parts inventory and have the luxury to set up the servo arms and pushrods ahead of time. This saves me a lot of work because it takes time to get the ball links operating smoothly with no drag.

The ball links are usually a little tight, which you don't want. You don't want sloppy either, but that is almost never a problem. You don't want any drag in the ball link because that can give you poor centering, so I like to loosen them up a little. 

The first thing I do is thread the ball link on to a pushrod. This makes it easier to hold on to, especially if you have arthritis. I use a small electric drill to spin the pushrod into the ball link, but you have to be careful you don't thread it in so deep that you damage the link. I use the clutch on the drill to keep this from happening. On these EXPs the threads usually go almost all the way in, and that way there is no chance they will ever pull out. I try to get it as close to bottomed out as I can. Once you get it in that deep, it is loathe to turn back out, so I use that end to bolt to the control horn, and make my trim adjustments by spinning the servo arm at the other end of the pushrod.


Then, I use an allen driver to pry the brass ball out of the plastic link itself. I pop the ball in and out a few times until it is nice and smooth, and can move around with no drag.

Pop the ball out as such....

And pop it back in thusly...
Sometimes after you bolt it on to the servo arm or control horn the ball link will tighten back up, so you have to pull it apart and start over.  Generally you want the bolt securing the ball link as tight as you can get it, but that can introduce drag into the ball link. This is why you have to tinker with it a bit. That's when you have to take it apart and start over.

For securing the ball links I depart from the hardware pack a little bit. I like to use Dubro 2mm X 12mm case hardened allen bolts. It is always easier to work with an allen driver than a screwdriver, and I've got a really nice set of Losi tools for this. I also like to use an aircraft locking nut, and then a regular hex nut on top of that and jam nut the two together. Once that is done, I apply the coup de grĂ¢ce in the form of a drop of medium CA to the exposed threads. Like this, the assembly can never come apart on it's own, but by spinning the nut off it will shatter the CA and you can take the assembly apart from there.

This is the control horn on my Laser, but the double nutting technique is the same.

All of this requires a lot of tinkering, but it pays big dividends to have smoothly operating, drag free pushrod systems. The servos work better and center better, and the aircraft flies more smoothly and precisely. Little details like this make a big difference in flight performance.

Tailwheel Assembly
I really like the EXP tailwheel assemblies. They also require a little bit of tinkering, but if you set one up properly they work brilliantly. No tailwheel assembly is going to stand up to repeated harrier landings, especially since a lot of times the plane simply stalls and drops the entire weight of the airplane onto the tailwheel. Still, I get away with it all the time because I took the time to set it up right the first time. I will bend the wire every so often, but we have a vise at the field, so it's no problem to chuck it up and bend it back.

Also remember that I do things like snap roll into a landing, do donuts and other such silliness, so I might be harder on the unit than a lot of people.

I also like that you can change the entire unit out in about 30 seconds by removing three screws. If you have a problem it's easy enough to fix right there.

The most important part of the process is grinding flat sports on the tailwheel wire where the steering arm and wheel collar grub nuts will sit. A flat spot gives those a larger surface to sit on, and less chance the arm can turn on the wire. You can either file it flat or hit it with a big Dremel grinding disc (my preferred method)..

Earlier steering arms were two pieces press fit together, and later they were threaded. However, the newest arms are now one piece machined aluminum. If you have one of those, disregard this paragraph.  I make sure the arm is threaded tightly onto the round center piece, then use a T pin to apply a drop of thin CA as shown in the photo below. It helps to tilt the arm up a little so the CA can wick into the joint. Also, remove the grub screw so in the case you get too much CA in there none of it glues that in! You only need a drop.

Finally, you have to get the center of the wire directly over the hinge line. If the wire and hinge line are not on the same axis, you can get binding, so it pays big dividends to take your time here. If you get it right you can tighten the screw that holds the arm to the rudder down tightly. Check rudder movement with the tailwheel assembly installed and hooked up to the rudder. If movement is good with no binding, you got it right.

It's hard to get it absolutely dead on, but if you are only off a little you can leave the screw that mounts the arm to the rudder a little loose.  It also helps a little to open the slot in the arm a little so the screw can slide a little easier.

Here you can see I have the tailwheel wire centered over the rudder hinge line, and that makes it operate with no binding.

The EXP tailwheel assembly works beautifully, but you do need to take a little extra time to get it working smoothly. I can set one up from package to finished in about five to ten minutes, and that's just puttering around with it and not trying to rush. If anything, it pays off if you don't rush and take the time to set it up right in one try. It is hard not to want to blast the project out and go fly it, so it takes patience to slow down and get all the details right. If you do, though, you get a plane that operates properly and smoothly. It's better to take the time in the shop and do it right than to have to fix something at the field.

Installing The HS85MG Servo On the Elevator
The EXP series was designed to operate on the Hitec HS65MG servos, but we soon found out with the quantum leap in airframe performance that we were asking too much for that servo on the elevator.  The MXS has always been set up to run the larger and more powerful HS85MG servo, though the Exta and Edge will benefit from that too.

The first step is to make sure that you do not move the servo output shaft forward or backwards. The push rods have a finite amount of threads, so if you get the servo in the wrong fore/aft location, you might end up with a push rod that is too long (fixable by snipping off a few threads) or too short (not fixable without a longer push rod).

Drop an HS65MG into the elevator servo hole, and mark the location of the servo output shaft on the fuselage with a magic market or felt pen. When you install the 85MG, you want the servo output shaft to line up with the mark you just make.

Next, line the 85MG up over the hole and guesstimate how much you will have to cut the opening to make the servo fit in the proper fore/aft location. As you can see, I simply laid the servo over the hole and then cut away the covering. From here we got lucky because to keep the output shaft in the same place, we just need to open the servo hole rearwards.

Now that the fore/aft location is locked in, let's drop the servo down. We do this for two reasons: first is that the servo is too wide to fit, and second, we need more space away from the stabilizer so the large Dubro servo arm we are going to use has clearance and doesn't rub on the bottom of the stab.

Here I use a straight edge to cut a straight line, and then I go back and drive the blade in deep. You can see there is a balsa block on the fuselage bottom and that needs to be relieved so the servo will sit down.

I tried really hard to get a good picture but this was the best I could do. You can see how I notched out the balsa block fuselage bottom and now the servo sits low enough. Seal all the covering edges down with a trim iron, and on mine I ran some CA in to seal the wood and lock the edges of the covering down. 

Lastly, here is the finished servo installation. You will have to dry fit the stab and servo with Dubro arm installed to make sure you have enough clearance, but I've done these before and I am confident opening the hole downward enough to get the servo in also drops it down enough.

One final trick is to push the servo as rearward as it will go in the servo hole. You probably won't get it absolutely perfect and will have a little slop, so move that servo backwards and that means you will have to turn the ball link further onto the push rod to get the elevator centered. One or two or three more threads going into the ball link is more margin against the push rod pulling out. You might even need to snip a thread of two off, but that's a lot better than not having enough threads on something like the elevator. 

As of this writing I don't have the stabilizer in yet, so I am going to cheat a bit and post a picture from my beloved and late, original blue extra EXP. You can see how important it is to have dropped the servo down because of the tight clearance the servo arm has to the bottom of the stabilizer.

I am using the longest arm in the Dubro pack, and the ball link is bolted to the second from the outside hole on that arm. I cut off the overhang of that last hole to get a little more clearance, but you can see it is still pretty tight. All my extra EXPs have been set up exactly this way and they have all flown beautifully.


Throttle Mix For Better Performance  

Awhile back, Andrew Jesky told me his trick for getting better throttle response out of an electric motor is to bump up the throttle trim until the motor starts idling. I tried this and it works great, but messing around with the trim was too much trouble considering that you can mix in just about anything with the fabulous new computer radios.

So, I tried a mix and put it on a switch. That way the idle is on/off. This is much quicker in the event of a crash or nose over than working the trim until you hit center. Just turn it off.

Some people have been having trouble with the latest ESCs shuddering on start up. The newest versions can sometimes be a little fussy to get going from a complete stop, but again, run an idle and it all goes away.

While this is not all that uncommon, running an idle stops this problem cold. Where some guys are having a bit of trouble is from absolute dead stopped. The motors kick back and forth and don't really want to get going, but if you run an idle, they will start up as soon as you flip the switch.

Now, this shuddering on start up is completely different from out of sync timing, which causes the motor to squeal and stop completely. Start up shuddering is only from dead stop and I've never seen it cause a problem in the air, because the motor never completely stops in the air unless you has the ESC set with the brake on.

I fly Futaba, so I run a channel three to channel three (throttle to throttle) mix. I flip it on, and then dial in the amount of idle I want and put it on my timer switch. The only thing you have to be careful of is to make sure your idle switch is set to off when you plug the battery in. Otherwise, it won't work. I put the idle on my timer switch because that makes one less thing to remember. I was always forgetting my timer before, but I never forget the idle.

For Futaba Users Only
I go to PMX (pre-mix) and set throttle as master, and throttle as slave. Put the mix on a switch, and I like my "A" switch for that simply because that's where my timer has always been. Turn the TX on with the "A" switch in the off position, plug the battery in, turn the Airboss switch on. Let the ESC play the tune, then flip on the "A" switch and dial in the mix until the motor idles. I usually end up with around a minus 27 to minus 30 mix.

After that, be careful that the "A" switch is off before you do anything. When the ESC is turned on, it will look for the endpoints of the throttle range, and if the switch is in the on position, it will ignore the mix and it won't work.

The procedure is: "idle" switch off, radio on, airplane on, flip "A" switch to start idle. If you screw it up and the idle doesn't work, flip the "A" switch off, unplug the battery and start over.

I know it sounds very complicated, but that's just how it plays out in writing. If you could see me do it, you'de agree that it's really pretty simple. It just translates into 1000 words.

Spektrum Users
This will also work witrh Spektrum radios and I have set a few up. Sadly, I am not that well versed in Spektrum programming and don't remember exacly how I did it. It's not that hard and if I can figure it ot you can. I just don't have one in front of I can use to help me explain it.

Finally, always take the propeller off when you are setting up this kind of programming. If you make a wrong move and get the motor running by accident a spinning propeller is especially dangerous when it surprises you.

Smoothing Out The 3D Landing

Sometimes these 48" 3D planes can be a little difficult to land. This seems odd because they otherwise fly so well, especially at low speeds. After a lot of research, flying, and tinkering, I think I have gotten to the bottom of it, and how to fix it.

First we fly these planes pretty tail heavy. We can get away with it because the planes have such light wing loadings but it does make the planes difficult to land. You can take any of the EXPs, move the battery forward, and they land like a baby. It's only when you get that CG near neutral that the plane gets a little weird at the stall. The critical moment is right as you are ready to flare the airplane out to land. That's when most guys get into trouble.

The pilot will fly the plane in, and the nose will rise a little. The pilot lets off the elevator but nothing happens. The nose won't come down on it's own, and the plane stalls and bounces. Typical 3D landing at most clubs.

This is why a lot of guys simply harrier land their 3D planes. With the wing already mostly stalled, it won't balloon up on you. The only problem is that when the tail wheel touches first the mains usually plop in harder than you want. A really smooth harrier landing is hard to hit perfect, but at least it doesn't balloon up on you.

In a bad balloon-type of landing, what happens is that since the rear stabilizer is so much smaller than the wing, it stalls first, and being tail heavy, the tail will drop. Since the wing is still flying, and now at a positive angle of attack, the plane will balloon up just enough to completely stall that wing. This would not be so bad if you were ready for it, but.....

You see it all the time with the newer 3D pilots who have not figured it out yet. They will go to flare out and the plane will start climbing on it's own, even after the pilot has let off the elevator. At that point, it is a little late to push in down elevator, and that low to the ground it's such a foreign thing that your instincts will fight you. These newer 3D pilots are used to a sport plane that you have to hold the nose up the whole way in.

So, the best answer would seem to be to make the plane behave more like a sport plane. You can do this by putting in some down trim when you are ready to land. You have to hold the nose up, and if it does balloon, all you do is ease off the elevator and the nose comes right back down. While this works beautifully when you can remember to do it, what a pain that is, and then you'de better remember to put your trim back before you fly again. Too much remembering required, but it would be a great solution if it was automatic.

Oh, wait....... with today's awesome computer radios, we can make it automatic! I use a 1% down elevator to low throttle mix. When you cut the throttle, the elevator goes down a little, about once click of trim worth. I have done this with both Futaba and Spektrum radios. It cures the ballooning problem, but outside of that it does not change the way the plane flies at all except it will give you a perfectly straight power-off down line.

With this mix you pretty much land like you would land a sport plane. Just drive it on in, and if the nose gets too high, just ease off the elevator a little, it will come right back down.
Like with any new mix, I suggest that you put it on a switch. That way if you don't like it, you can flip it off, land like always, and clear it out of your programming. Try it and I think you will like it. I run this mix on all my 48" planes with no switch. I even dial it in on brand new planes because I know I am going to need it.

It just wouldn't be an Extreme Aviation report without a video, would it? This is a compilation of three flights that were not especially noteworthy, but once I edited out the lame stuff it was actually pretty decent. Add a spacey soundtrack and you've got a great video................

Notice on the very last landing, after the closing credits, that the plane comes in low and starts to rise back up again. It's trying to balloon up on me, but I instinctually ease off the elevator a bit, the mix does it's job and it's a perfect landing. I am doing my landings more and more like this because it is so much easier on the equipment than a harrier landing. Half my harrier landings are more like downward plops, but you can't beat a mains only roll out for soft and pretty.

Thanks to my friend Kevin for the superb camera work.

Working With Pull Cable Systems

I've had so much fun with my 48" 3DHS Demonstrator Edge that I wanted to build another one. I've been threatening to write an article on pull cable set up and this gave me an excuse to build another Demonstrator even though my first one is still in terrific shape. Maybe I'm just greedy.

For those who have never done a pull system, it can be quite intimidating, but it's really just as easy as using a pushrod, just different. Like anything else, you need to know a few tricks and you learn those by doing them, and hopefully, from reading this article.

Setting Up The Pull System

My first pull system had me scratching my head and cursing a little, but I learned enough from that to make subsequent ones go smoother. It's not that hard and there are no mysteries. After you do a couple you will wonder why you were intimidated to begin with. What I'm going to try to do is show you some of the little tricks I learned the first few times.

If there are any hard and fast rules they are that you want a drag free and slop free system. The rudder has to move smoothly with no drag coming from a bad hinge job or ill fitted tailwheel assembly. The swivel connectors on the servo arms also have to have no drag on them, and as little slop as you can manage without getting them so tight they drag. If there is ever any doubt on any part of this, always go for smooth and drag free, slop free operation. This is critical for good rudder centering and makes for a good flying and nice tracking plane.

Cleaning Up The Cable Exits
The slots for the cable are already laser cut into the fuselage sides, and the covering is slit so the wires can pass through. The first step it to tuck the covering into the slot with a trim iron. Get them out of the way so they don't put any drag on the cables. You can either cut them flush with the edge of the slot or tuck them in, but tucking them in makes for a neater and cleaner looking job. Here you want to use low heat to avoid the iron sticking and pulling the printing off. Take your time, do a neat job. I think you'll agree this looks a lot cleaner than leaving it loose.

The Cable Ends
Now, thread the ball link onto the threaded connector piece. You can either hold the threaded connector with a pair of pliers and spin the ball link on by hand, or chuck the connector up in a small drill and spin it into the ball link. If you have arthritis, using the drill will make life a lot easier.

The connector will be easier to handle this way because it gives you something to grip. I suggest threading it on all the way, then backing it off five turns or so. This will give you some additional adjustment should you need it later.

With any operation, the cleanest and most tidy job is going to be the best solution. The least clean part of any cable installation are the cable ends and crimp pieces, and I've done my best to make that neater. Here is how the manual calls for the cable ends to be assembled. This works really well, though it's a bit messy for my taste. We are still going to do it the way the manual calls for, though we are going to tidy it up a bit.

Follow the manual and you will get what you see below. Again, this works well, but we're going to clean it up a little. I've put a battery on the ball link to hold it down and aid in getting a better photo.

We are not really going to deviate from the manual here. We are just going to go one step further in making it look better. Again, the cleanest solution is the best one. What I try to do is eliminate the loop in the cable and the extra wire sticking out. First, I pull the wire in the loop tight enough to take the loop out. This goes a long way toward a cleaner appearance. Then I move the crimp piece closer to the threaded end piece to make the whole thing smaller and visually less intrusive.

Once you get it all lined up. take a pair of pliers and smash the crimp piece flat. Just to be sure, put a drop of thin CA on the wire and hold the piece so gravity helps it run into the crimp piece. Snip off the loose end of the cable and the whole thing looks a lot better. It's still pretty ugly. but we're not quite done.

Finally. I use a piece of heat shrink tubing to cover the whole thing up and make a nice presentation.

Setting Up The Servo Arms
Now we take care of the other end.  Here I am using the standard Hitec double arm that comes with the servo and the 3DHS swivel connectors. These are nice because they afford easy cable tension adjustment.

First, drill the outer holes in the servo arm with a 5/64  size drill. I use a little hand drill from the Hobbico set, but in a pinch you can get away with hogging it out by spinning #11 Xacto blade in the hole. Drilling can leave behind some flash around the hole, and this can interfere with the swivels moving smoothly. I use an emery board to lightly sand the top and bottom of the arm. Good, smooth operation will help with proper servo centering.

On the newest 3DHS swivel connectors the threads on the end are a little tighter so the nut spins on a little harder. This is a good thing because it makes it harder for it to come loose. Get the nut as tight as you can get it without introducing any drag. Again, you always want smooth, drag free operation on any control system.

As you can see, the threaded end is a little long, and you have a few threads sticking out. The reason for this is you want to put to put CA on these threads to lock the nut on. I like to use a T pin to apply some thin CA to the exposed threads, and after that sets up, a dab of medium CA. This assures it's not going to come apart.

When you put the arm onto the rudder servo, use the sub trim in the transmitter to center it.

Hooking It All Up
With the cables attached to the control arm on the rudder and cables run forward into the fuselage, now it's time to hook them to the servo. Here I run the forward threaded end pieces halfway into the swivel connector,  and this gives me adjustment both fore and aft, and remember, we have some adjustment in the rear if we need it.

Now you want the rudder to stay centered so you can get the cable tension close, and for this I usually tape the rudder counter balance to the fin. Since the Demonstrator uses printed covering, I don't want to risk damaging it, so I have the wife or a friend  pinch the two together. 
I like to install one cable at a time because it's easier that way and you have less chance of mixing the cables up.  You want the cables to cross over top of each other inside the fuselage so they line up straighter to the servo. By doing one cable at a time, you simply start with the left cable and attach it to the right side of the servo arm and the right cable to the left arm. I don't know why, but I always start with the left cable.

 Make sure you slide the crimp piece onto the cable first.  Starting with the left cable, run it through the right side forward threaded connector piece. Pull the cable tight. You want to be careful that you don't pull so tight that you start breaking things, but you want it tight enough that you won't run out of adjustment later. Usually the cables end up not being as tight as you thought you had them, so get the slack out. If it's either too tight or two loose, we left ourselves some adjustment by centering the forward connector pieces in the swivel, and remember we also left ourseves some emergency adjustment at the rear with the ball links.

 One neat trick here (see above) is to get the cable tight, then bend it backwards at the connector. This will help it stay tight and not slip while you are running the wire back through the crimp piece. You can see I pulled the wire tight and then folded it over the connector. You can pinch the cable down on the connector with one hand and it's not going to come loose. Then you slide the other end into the crimp piece with your free hand (which has slid back out of sight in the photo).

Like so............

Now you do the loop, which I did not get a picture of, but it's the same as we did on the other end and the same as in the manual. Again, I like to pull the loop tight,  but also again, be careful you don't slip and start breaking stuff. If it's all good and still tight, smash the crimp piece down to lock that part of the adjustment in. Apply some thin CA to the crimp like you did on the rear and it's almost done. Put a paper towel in the bottom of the fuselage just in case you spill any CA. From there, snip off any excess wire, remove the threaded end pieces from the swivel and use heat shrink on the end and crimp pieces.

Do the other side exactly the same way and you're almost home. Yes, I am well aware the rest of the radio installation looks like a rat's nest, but we'll clean that up later

You may notice that my connectors did not even need adjusting. I got the centering and tension
perfect just by pulling the cables tight. Like I say, they normally come out a little looser than you planned, and keeping the slack out to begin with made it perfect. After you do one or two of these you can expect the same kind of results. None of this is a mystery. You just need to do one or two to get used to it, and then it's easy as pie.

Now all  the hard stuff is all done now. All that is left is the final adjustment.

Odds are pretty good you have it almost perfect. You want the cables tight enough that there is no sag in them, and there is no slop in the rudder. On the other hand, you don't want to get the cables guitar string tight either. That will kill the centering. Just adjust the cables so there is no sag in them, and no tighter. Assuming the rudder and swivel adjusters move smoothly with no drag, the rudder should center perfectly. if not, you probably have it too tight.

Slide the forward threaded connectors in or out of the swivel connectors to get the rudder perfectly centered, then tighten them down.  Generally, you don't want the cables so loose that you can move the rudder, and you don't want them so tight that the rudder doesn't center properly. The best rule of thumb is to get them tight enough that they don't sag, and no more. If you get them guitar string tight the rudder will center poorly and eventually the servo will burn out. If you get them too loose the rudder can move when the servo doesn't and it will center poorly to boot, which is never good.

Another good rule of thumb is that if the rudder centers well, you are pretty close. Finally, as long as the rudder will repeatedly center, leave it alone!  If you get it right now, you may have to adjust (usually tightening) the cables once or twice over the lifetime of the aircraft, but outside of that, it's pretty maintenance free. A little patience in getting it right now pays the dividend of you not having to mess with it later.

Generally I try to take a little pride in my writing, but this procedure has been challenging to put into written word. I tried to explain this to a friend out of state over the phone and I did a poor job. Later he visited me and brought his new Demonstrator. It was finished except for the pull system, and I showed him how to do it in five minutes. Showing was a heck of a lot easier than explaining, and infinitely easier to understand, and I tried to keep that in mind when I wrote this. I hope you will find this clear and helpful.

Working With Vinyl Graphics

There are a few different ways to go for putting vinyl graphics on your plane, but for the purposes of this article we're going to talk about the two most popular.

Note: To avoid confusion between the two types of decals, from this point on in the article we will refer to the single piece sheet decals that come with the kits as "kit decals" and B and E high quality "air release" type of decals as simply "decals." There are also two different ways to apply both types of decals, and we will also get into that later in the article.

"Kit Decals"
First are the decals that come with most of the kits. They are printed on a single sheet of clear vinyl, and you have to cut each one out, peel off the backing and stick it down. They are extremely grippy and unless you use a decal solution they are very difficult to position. You can forget about sliding them on because they simply stick too vociferously. Since on any text part of the decal there is clear vinyl between each letter, that's a lot of area to trap air under. To get good results with this type of decal, you just about have to use a decal solution.

Generally I don't like these decals because it is a lot of work to cut them all out, they are hard to work with and they don't look nearly as good as the next type of decal were will be talking about. They still work, and since they come with the kit it makes sense to use them and save the money, provided you are not so super picky and critical as I am.

High Quality Air release Vinyl Decals.
Lately I have been using a lot of high quality vinyl "decals" from B and E Graphix. They now use the "air release" type of vinyl which has little air channels on the back side of the decal. These allow air to be pushed toward the edge of the decal and out. Sometimes the air will escape on it's own if you just let the thing sit for an hour or so. This makes air bubbles under the decal pretty close to a thing of the past.

Applying this kind of decal is also easier because, for one, it is much more forgiving to work with. It you get a decal a little crooked you can get it back up if you are careful. This is much easier than when working with the other type of decal which is so grippy you have no chance to slide it around and adjust it.

On these types of decals you have a backing, of course, but also there is a piece of backing on the front of the covering. This is called "application tape." The reason for this additional piece of tape is because each letter in a text decal is it's own separate piece of vinyl with no clear material between those letters. For instance, on an "Extreme Flight" decal, the "E" and the "X" and the "T" and all the rest of the letters are all separate pieces of vinyl. The application tape simply keeps all the letters aligned until you can get them down, and then you peel the outer piece of application tape off, and you are done.

There are two ways to apply these type of decals. One way is simply peel and stick and then peel off the outer application tape. The other is to use decal solvent, which we will cover later. For now we are just going to peel and stick.

Perhaps a little too confusing to explain in words when pictures work so well, so here are some pictures. As you can see at the top of the picture, the decals still come on one sheet, or in the case of the laser, because there are so many decals, two sheets. Here I have the SFG all cleaned off with lacquer thinner (removes any covering glue residue) and an SFG decal cut from the main sheet.

Below I have peeled the backing partially off so you can see what it looks like and how the three layers are put together.

Now you simply align it and lay it on the SFG. Rub it down and we are almost done.


Now you can clearly see how the application tape does it's job in keeping all the separate pieces aligned for, well ..... application. You just peel it off. It is helpful to peel the tape off in a direction parallel to the surface. This helps you not pull the decal back off or pull the covering from the wood.

And now, the finished SFG.

Application Fluid
Previously I was using Windex for my" kit decals," but I have since learned that the ammonia attacks and dissolves the decal glue and makes the edges not stick quite so well. "Rapic Tac" application fluid works so much better because it is inert toward the glue, and it also seems to allow air to escape better, especially when working with "kit" decals.

For the rest of my new Laser I used "Rapid Tac" decal application fluid. B and E sells this, but you can also get it at most graphics stores. It is really good stuff and makes the job a lot easier, especially on the Laser.  The whole idea of application fluid is to allow you to slide the decal around until you get it where you want it, and then squeegee the fluid and air out so the decal will stick.

According to the B and E web page: Using Rapid Tac Application fluid can often allow a large graphic to be installed with one person where two people were required to perform the same installation dry. Rapid Tac Application Fluid also cleans the surface without leaving residues ensuring a contaminant free installation. It then helps to -float- the vinyl film until it is properly positioned.

Also on the B and e web page are instructions for using Rapid Tac.

I found all of this to be true. The stuff works really, really well and gives you are very nicely finished plane.

Previously, for my high quality decals I just peeled and stuck them because none of them were really big and perfect alignment was not super crucial. The Laser, however, is such a special plane for me that everything on it had to be absolutely micrometer perfect.  The laser has long stripes and stars, and near perfect alignment is critical to get an great looking replica of Leo Loudenslager's awesome plane.

Of course, I had B and E cut me up a set of beautiful air release decals. It was putting them on that was going to be a bit tricky. I built one Laser just peeling and sticking the long stripes, and while it came out well, it was a huge amount of work and stress getting it all aligned perfectly, though admittedly, the stress was only bad because this plane means so much to me.

For this Laser, I went with Rapic Tac and it was a whole new world of easy. You can use all the Rapid Tac you want because it does not effect the glue. You can wet down the plane and the back of the decal too and it makes no difference except making it all easier to slide around.

Unfortunately my camera started acting all crazy halfway through this project, so I did not get all the photos I wanted. For now, here is a picture of the soft plastic squeegee I got at the graphics store, though I believe B and E has them too.

What you do is peel off the backing tape and then spray the area you want to apply the decal to with Rapic Tac. Position the decal by sliding it around on the plane until you get it where you want it. Then squeegee the fluid and air bubbles out from under the decal. On the Laser this was especially helpful to be able to slide the decal onto position because alignment was so critical to get a great looking plane.

Not wanting to screw up an expensive decal set I experimented on a wrecked wing using standard kit decals. Rapid Tac is especially essential with those type of decals because they are so grippy that you can almost never get them straight and with no bubbles. With Rapid Tac they just slide into place where you want them and then you squeegee out the fluid and air. It makes for a much better looking kit decal, but it is still not as good as high quality vinyl decals.

I wasn't able to get any pictures of the Laser decal application but I will take some when I get a new camera and edit the article. However, as you can see, with the long, flowing stripes the decals have to be perfect for the plane to look good. Using the air release vinyl decals and Rapid Tac, I would get one end of the stripe positioned and hold it in place while I slid the other end where I wanted it.

Once you have built so many planes and applied so many stickers and such you develop an eye for getting things straight. Being able to slide the decal exactly where you want it makes things so much easier, whether it is a standard kit decal or high quality air release graphics.

 In the end, it's mostly up to you how well your plane does or doesn't fly. Take your time with everything and make it as good as you know how. Time is not an issue and there are no macho points for getting it done fast. If you skip a detail or resign yourself that something marginal is "good enough," you could very easily end up with a plane that doesn't trim out well, fly straight, or even buy yourself a crash.
With most manufacturers, always follow the manual and the recommended control/expo/rate set up, at least as a place to start.
Remember that details count ... all the details count. Take your time especially to do one last thorough inspection of everything, especially making sure the controls are moving the right direction and your rates and expos are right. That alone could save you an airplane.


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