servos for Guillows RC conversions

[woundedbear]

I have Tactic transmitters so I am pretty much stuck with using Tactic receivers (unless you guys know of any other receivers that will work with Tactic TTX600 and TTX650 transmitters?) for my RC conversions. Tactic makes a 4 channel receiver that weighs in at 1.8 grams and requires 4-6 volts of power for the receiver itself. Tactic's other 4 channel receiver has two built in servos it weighs 4.7 grams and requires 3 -4.2 volts of power. The two Tactic 4 channel receivers use micro servo connectors. Then there are the two 6 channel receivers by Tactic. One has twin antennas (I have 1 of these so far). It weighs in at 9.5 grams and requires 4 to 6 volts of power. The other 6 channel Tactic receiver has 1 antenna weighs 8.9 grams and requires 4-6 volts to operate the receiver itself. Then there's the servos themselves. I don't think you have to use Tactic brand servos but I could be wrong about that, here again, I need the advice of the folks here on this forum. My knowledge of the electronics needed to build a Radio Controlled airplane are woefully inadequate. I have picked up on a few things just by reading here on this forum. I have learned from Bill Gaylord that the plugs used by some of the servos makers are heavy and by cutting these plugs off and soldering the connections directly to the receiver not only makes for a better connection but saves weight as well. This brings me to my big question," weight", and how to save weight on an RC conversion? How much can the servos weigh when doing an RC conversion with a Guillows 1/16th scale model kit? Using one servo to control both ailerons is a good way to save weight, but using one servo for each aileron gives better control. I have learned that by using one servo for each aileron you can adjust the throws so that the aileron that is deflecting the wing downwards needs to move more than when the aileron that is deflecting the wing upwards. This can prevent adverse yaw, or is this wrong? Most of the conversions that I have read about don't include adding flaps (I have read that when working with model planes in the 1/16th scale adding flaps tends to cause ballooning when trying to land). But adding retracting landing gear is something that I want to do. I saw a Guillows conversion on youtube where a Dude added scale retracts to a 400 series P-40 that was so cool. I can't help myself when I get around to building a P-40 I have to do that. Of course, first, I'll have to do a simple 4 channel conversion or maybe just a 3 channel with only, throttle, elevator, and rudder control to keep things simple. Here any advice would be helpful.

[davidchoate]

There is nothing wrong with Tactic. They make good stuff. I got a spektrum Dx6i Transmitter or Tx for short, and it is good for my needs, but I also have been wanting a Tactic 6 channel Tx because of their "AnyLink" system which allows You to use their Tx's with other Brands. Spektrum is nice because it is compatible with E-flite, Orange, and HURC RC Receivers or Rx's for short. Just check out their website for info, or a better forum for more in depth advice is RC Groups Forum. Check it out, and I know You like Surfing down the information Super Highway so It'll be Fun as well as educational.

[David Lewis]

wounded bear wrote: "I have learned that by using one servo for each aileron you can adjust the throws so that the aileron that is deflecting the wing downwards needs to move more than when the aileron that is deflecting the wing upwards. This can prevent adverse yaw, or is this wrong?"

David Lewis wrote: It's correct. On full scale planes, getting rid of adverse yaw makes turns easier to coordinate and, if the airplane is spirally unstable, that's OK. On a small model, we also deal with very low Re, in which case the downward deflected aileron tends to impose a drag penalty while, at the same time, reducing lift on that (up-going) wing. A model using ailerons has marginal-to-inadequate roll authority to begin with. Anything that increases drag and reduces lift at the same time is thus to be avoided. (Note also that differential aileron throw can be achieved using only one servo.)

Flaps might make an airplane more liable to balloon when you deploy them, but the bigger problem is that flaps don't increase the lift coefficient, so I don't see much point in them.

Another option to reduce weight is to forgo ailerons altogether. If you have enough dihedral, you can use the rudder to turn.

[davidchoate]

I wish to add that to make ailerons work on small, slow scale models they should be made larger than scale. I have noticed that all small foam RTF's that the ailerons are run about 3/4 the length of the TE. Also I have learned the hard way the importance of setting up your servo travel, etc, and really read the manual of your radio. And read up on stuff like choosing a motor and prop etc. It seemed overwhelming to me at first glance, but little by little I have begun to understand. I have much to learn, but I have the persistence. Failure doesn't effect My Love of this stuff at all.

[woundedbear]

Hello davidchoate, I have been picking everyone's brains here on this forum and have come to the conclusion that first I will have to build my Guillows models as rubber powered free flight airplanes in order to learn the building skills to convert one to an RC model airplane. I made it a point to thank everybody here for all of the advice that I have been given. I would like to thank you and Bill Gaylord, NcGunny, glassblade and the list could go on for hours, but you have all been so generous with your time and experience in building these Guillows kits First you have to learn to crawl, then you must learn to walk before you can run. I made the mistake of thinking I could start out running Learning is a big part of enjoying this hobby. I am currently working on a 400 series P-51 kit that will be a rubber powered free flight model. My income is fixed. Fixed in a bad way, "as in tomcat fixed that is". I have so many kits that I have not compleated. I have been buying buying tools for the last 3 months, getting the formers and wing ribs 90 degrees to the build board is not as easy as it seems and cutting stringer stock with a balsa stripper tool isn't easy either, but I'm not one to, "give up", so I have much to learn about working with contest balsa wood. I was a wood pretty good worker in my younger days, but there is a learning curve to working with contest weight balsa wood. Maybe one day, "Lord willing and the creek don't rise", I'll be able to get a simple digital camera and post some photographs of my efforts here of the forum, maybe by the time I have the "know how" to do an RC conversion Guillows will have their 1000 and 2000 series kits in laser cut form and will have added, "hopefully", some kits that are designed to be built as RC model airplanes in some larger scales 1/12th scale and dare I hope 1/8th scale kits with the vacuum formed parts to match, would be nice