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  1. Junior World Champs Results Online
  2. Buying a second hand model with an electronic timer

Junior World Champs Results Online
The results of the 2018 Junior World have been scanned are on line at the Web Site of FF Wolrd champs results, maintained by Ian Kaynes.  The link gives all the World and Continental Champs held so far in 2018.

http://www.freeflightnews.org.uk/champs/ch18/ff18.htm

Buying a second hand model with an electronic timer
From: Magic Timers – magictimers@yahoo.com

Recently at Magic Timers we have questions from people who have bought an airplane with a Magic Timer.  On FaceBook we I have seen similar questions from people who have bought secondhand airplanes with other electronic timers. This article refers to Magic Timers but the principles  apply to most electronic timers.

One of the reasons why someone buys an airplane with and electronic timer is to get one that is working. These days there are many good airplanes around that have become surplus to the owner’s needs and will serve the new owner very well. Many new owners may not understand the details of buying a model with electronic timers so here are some hints.

The very first thing to understand is that the “flight program” that goes in an electronic model is set up for each specific airplane and that you must get that flight program with the model.  If you have an F1A for example you cannot just put the flight program from a friends F1A and expect it to work straight off. Make sure you get the flight program.

What to do if you buy a model with a Magic Timer

1. Purpose

The purpose of this document is to help people get started when they buy a model, typically a F1A or F1B that is fitted with a Magic Timer.  Under these circumstances it is assumed that the timer is already mounted in the model and everything that is necessary for the model to fly is there.  It is also assumes that the model is either in flying trim or has been set up on the bench very close to flying trim.

The person who built the model will have made some decision on how to mount the timer, what servos and batteries to use and what way to control the flying of the model.  The new owner of the model will need to know the result of these decisions as well as basic information about the Magic timer that has been used.

Note that there are a number of different models Magic Timer so you need to know what timer is installed in the model.

2. Questions to Ask

Before you take delivery of the model as the supplier, if it is a new model or previous owner for a second hand model the following questions.

Timer

  • What Model Magic Timer?
  • How servos?
  • What is the timer version number?

Model battery

  • What type of battery is in the model?
  • How many cells?
  • What capacity in maH?
  • What cable is required to charge the battery? Is it included?
  • What battery charger do you recommend?

Servos

  • How many servos are in the model? Note that the number of servos in the model may be less than the number that the timer will support.
  • What make and model or servo is used.

Other equipment

  • Does the model include a device e.g. Palm Pilot to program the model?
  • Does the model include a cable to go from the model to the programming device?
  • If not what kind of programming cable is needed?
  • What kind of tow hook is used? F1A only
  • Does the Tow Hook have a relatch servo?
  • If it is a relatch hook, what kind of line tension sensor is in the model?
  • Is it an M&K style Impulse hook?
  • Is the model fitted with a Radio D/T? If so what make?
  • If there is no Radio D/T fitted does the timer used support it?  Note all recent Magic timers support some forms of RDT.
  • If not RDT fitted is there wiring for one?  This is because wires may be needed to go from the timer to the RDT. These might need to be built into the model.

Note that the initial set up of the model and the timer settings, to make the model fly properly takes some experience both with trimming in general and with electronic timers in particular. One of the reasons for buying a second hand model is that it has been set up and you can learn from it.  Make sure that the timer has been set up for the model and that you have a back up copy of the flight program. The flight program is the timer setting that will make the model fly properly.  There will be the flight program in the timer but as the seller to give you a paper copy.  One way of doing  this with a  Magic Timer is to photograph the Super Magic (the timer setting program on  the Palm) screens.

The timer settings  are to achieve the flying results that you want.  They move the control surface at the time you set and in some case the amount the surface moves. The correct setting depend on the servos, battery, tow hook, and linkage to the control surfaces or each individual model.  When buying a second hand model you are buying  this information, make sure you get it and that  it is correct!

3. What you need and what you do first?

What you need

  • So you have the model?
  • A way to charge the battery?
  • A way to program the model

First thing with the person you got the model from:

  • Make sure the timer battery is fully charged
  • Assemble the model.
  • Connect all the control lines
  • Put the model through a flight sequence on the ground.

For a F1A model do all of this on the ground in your workshop.

  • Assemble the model including the Radio DT and tracker
  • Get a screw driver or similar to open and close the tow hook.
  • Close (also known as latch) the hook
  • Turn the timer on.
  • Move the hook back and forward and make sure the auto rudder, wing wiggler, etc. work
  • Pull the hook forward and holding the hook forward unlatch the hook.
  • Let the hook swing into a backward position.
  • This is the launch position and the timer should take the model through the launch sequence. This is probably a bunt sequence
  • Let the timer run for length of the flight and watch the model D/T

If that worked and the model has a Radio DT repeat the above sequence until the model “launches”
Wait for 10 seconds then press the Radio D/T button and watch the model D/T

If you do not know how to do any of these things or they do not work as the person you bought the model from.

For a F1B model do all of this on the ground in your workshop.

  • Assemble the model including the Radio DT and tracker
  •  Do not wind the rubber motor
  • Turn the timer on.
  • Push the timer start button
  • A buzzer should sound and LED comes on.
  • Release the start button and the timer will start
  • Watch it go through the flight sequence, typically
  • Start prop
  • VIT
  • Wing Wiggler
  • Glide Rudder
  • Some model may have more functions.
  • Let the timer run for length of the flight and watch the model D/T

If that worked and the model has a Radio DT repeat the above sequence until the model “launches”
Wait for the glide rudder to kick in then press the Radio D/T button and watch the model D/T

If that worked, fully wind a rubber motor, load it into the model and repeat the above sequence until the model “launches”. Be sure to hold the model firmly when the rubber motor starts as it will try and fly in you workshop! Make sure the prop will not hit anything.

If you do not know how to do any of these things or they do not work ask the person you bought the model from.

Save the initial timer settings.

Now that you have shown that the timer and airplane basically work together you need to save a copy of the timer program.  This is in case you make changes to the program and mess something up and need to return to a point where things worked.

Removing the timer from the airplane

Do not remove the timer unless there is a problem. If you need to remove the timer from the airplane . Before you remove the timer from the airplane, take a photo. During the removal process at each step take a photo.  It is very important to reconnect the  wires in the same place ! Failure to do this could cause serious problems and damage the timer. Pinout sheets exist for each Magic Timer , if you did get one with the model you can get one from Magic Timers.  Typically the timers are made to be light and small, this means that they may not have a full complement of in built protections against connecting the wrong thing to the wrong place.  For example connecting a tow or start button where a servo should go can seriously damage a timer. Never just plug it in to see what happens,  if you do not know where you are plugging it. Because what happens could be a column of smoke.