Let's talk about controls and pushrods for our giant scale models. We've already covered the servo requirements so we'll continue from there, adding the pushrods. Just like the servos, the pushrod requirements are different for the different positions. We'll take a look at the elevator first, but before that let me make a few comments on clevices.

I personally feel that clevices are the weak link in many planes. In most cases they are just an afterthought when you are putting together the equipment for your plane. Just grab a few at the hobby shop, screw them on, and hook them up. This usually works fine with the smaller planes, but with the giants, you have to be more careful. I have some feelings about which clevice to use I have picked up through experience that I will pass on to you. I personally do not like to use the small metal clevices or plastic clevices with a plastic pin on either of the primary controls, elevator or aileron. I have had pin failures with both types and I have stripped the threaded portion of both types. This was on a high performance fun fly type plane and before I started using a split elevator and a "Y" on the pushrod, but the stress was probably about what you would get in a giant scale plane. I will use them, however, on rudders and throttles. My preference for clevices on small planes, and for some applications on giant planes, is the Kraft clevis. It is black plastic clevice with a metal pin. I have yet to have a failure with a Kraft clevice.

For my giant scale planes, I have been using the DuBro 4-40 clevics. They have worked fine, but they tend to break after you take them off and put them back on 3 or 4 times. Be careful when you make trim adjustments on a new plane and always carry some spares. I haven't tried the giant ball link clevices yet, but I have heard that it works well. There are a couple of clevices that have a bolt for a pin. These ought to be very strong, just use a lock nut so it doesn't come apart at the wrong time. I plan to try some on a future plane.

Now that I have stripped all the clevices bare, let's get on with the pushrods. We'll look at the elevator and rudder first. As you recall, these two controls can either use 1 or 2 servos. There are several different types of pushrods that can be used with these servos, so I'm going to list them in a table:

ONE SERVO	COMMENTS
1 Pushrod, 1 control horn	Poor
1 Pushrod, Y with 2 horns (Split Elevator)	Good
Pull-pull cable	Giant size Best, regular Goldenrod best
Pull-pull, goldenrod	On smaller planes on rudder

TWO SERVOS	COMMENTS
Doubler, 1 pushrod, 1 horn	Poor
Doubler, 1 pushrod, Y with 2 horns	Good
1 Pushrod on each servo (Split Elevator)	Good

Let's go over the table. First, what do you use for pushrods? I like fiberglass arrow shafts, but you can use large dowels. Absolutely do not use balsa as you might for a small plane. For any type, you should have bracing in a couple of the fuselage bulkheads so they don't bow under load. Next, why don't I like one large control horn and a giant type clevice? Well, you are putting all the load on one horn and clevice. I know that you're doing the same thing at the servo end if you use one giant servo and a single pushrod, but I've had a lot more trouble at the elevator end than at the servo end, so I like the split elevator configuration. It also allows you to adjust each side separately.

Let me also explain the "Y" I have mentioned. You use 2 4-40 rods on the end of your arrow shaft or dowel. They are bent outward, looking like a sort of "Y" and exit the fuselage through a slot on either side. You use a control horn on each elevator half and these elevator halves are not connected together.

When I talk about two separate pushrods, I mean just that, you use 2 servos. Each one has a pushrod that is connected to a side of the elevator just like it was two separate planes. The elevator halves are not connected. You can see that in this case, it is nice to have servos that are the same speed and have the same movement. It's hard to tell a difference with a small plane, but with a giant, you'll notice it.

My preference for pushrods is one of these three: split elevator and a doubler with the Y, split elevator with two separate pushrods, or one large servo and a pull-pull system. For the rudder, I nearly always use the pull-pull system. The rudder usually has more travel than the elevator so any slack in the servo gears or in the pushrod connection will result in a large amount of slop in the rudder. The pull-pull system allows you to tighten up and remove any slop in the control system.

The ailerons are a different setup. I invariably use a servo in each wing with a metal 4-40 rod going straight to the control horn. I know there are big belcranks which will allow you to make a more hidden control system, but my experience with belcranks has been that they usually produce slop in the control system. As a former pattern flyer, any kind of slop usually leads to flutter and that is a big screaming NOOOOO!!! You may have good luck with belcranks. I do think that a servo in the underside of each wing is a lot easier. My wife, Phyllis, contends that things like rubber bands, mufflers, and pushrods are invisible. She says that modelers assume that they're always going to be there so they don't even see them.

If you think there is something special about the throttle on giant scale planes, you're wrong. They may work backwards if you have a belcrank arrangement like on the Zenoah Quartz, but that's what reversing switches are for. Aren't they great?! Take all my rate and expos and mixers, but don't take my reversing switch. Some people use Goldenrod, but I use the same cable that I have always used, Sullivan gold colored.

Right now, the planes that Phyllis and I are flying have the following setups: Phyllis' Duster has one elevator pull-pull cable, rudder pull-pull cable, ailerons one servo in each wing with 4-40 rods. My Spinks has one elevator-doubler with Y connection, rudder pull-pull cable, ailerons one servo in each wing with 4-40 rods. These setups are working well. Mine is stronger, but I stress the plane more. Plyllis' is flown in a more normal manner. Remember if you think you are going to really put some stress on your plane, lots of snaps, spins, and lomcevaks, go with the stronger setup. Keep it safe.