TEXAS TIMERS START ON LAUNCH SWITCH
Click on the image to see a larger photo and additional details
WHAT DOES IT DO?
A Start on Launch Switch, or Remote Start Switch lets the timer start at the instant the plane is released. This assumes you have the timer set at the exact point to give you the correct engine run.
WHY WOULD YOU WANT IT?
Many of the top flyers recognize the importance of having the plane in just the right position at launch. This can be complicated if you have to look at the timer, trip it, and then get the plane in the best attitude, all in a fraction of a second. So, such a switch lets you concentrate fully on the plane and your technique, knowing that at the exact instant you let loose of the plane, the timer starts. This is not limited to FAI flying. It applies to all competitive events. A side benefit is that you are less likely to forget to start the timer as it happens automatically when you grasp the fuselage for launch.
HOW IS THIS DONE?
Every product and method we have seen uses the same fundamental way of starting the timer, regardless of what brand of timer it is. As soon as the model is released, a small wire that had been fit into the timer is pulled out, letting the clock start. All use some sort of spring mechanism to retract the wire. How the wire interfaces with the clock to hold it off can vary with the brand of the timer, but they are all quite similar. They are identical for all timers using the type of clock we use. The fine wire is typically 0.024 inch diameter, but this is not a magic size. With our type of clock, the wire hits or rests on the small vibrating speed regulator. At this point in the mechanism, even the lightest touch will stop the clock. Fortunately, this vibrator is made of steel and is not a delicate component of the clock. As soon as the wire is removed, the clock starts. Obviously, the modeler has to fit this carefully and provide guides inside the fuselage for the wire to ensure it consistently hits the small vibrator` in the desired place, even with engine vibration. This is where you do testing and make it the way you want.
WHAT ELSE IS IMPORTANT?
To begin with, you want the switch to hold the timer off without you needing to do anything while you are getting ready to fly and starting your engine. You have enough to do, without having to fuss with anything at this point. Next, you want to be able to "arm" the switch so it will trip as soon as you release the model. Again, you do not need the hassle of having to do anything that is not totally natural to do this. Your mind is on a million things, and most should be more important than arming the switch.
We recognized several years ago that we needed a Remote Start Switch in our product line and must have looked at a dozen products on the market (almost all from East Europe) and played with half of them at one time or another. Some were very crude, but most were real works of art. Unfortunately, what was very sophisticated in design, also turned out to be fragile or delicate. Certainly not robust, or very forgiving of abuse. Even accidental abuse. One very nice unit broke after only a few cycles of operation. If it breaks that easy, what the heck is it going to do in a plane with a big honking engine? Not a pretty thought! One of our prime goals is to only provide products that we would be confident to use ourselves.
Additionally, we wanted the switch to be affordable as well as totally reliable. No custom machine work or watchmaker assembly and no delicate mechanism. It just had to be a "work every time" design, and without thinking about it. Quite frankly, we struggled with this over a lot of design approaches. One approach looked pretty good, but costly to make.
A well known flyer told us about a really good switch he had seen and used. This is the "Lynch Trigger" by Bill Lynch, accomplished machinist, supplier of many unique and useful gadgets for FAI power, as well as designer of the Hurry Up, Pegasus, and Bandit F1J models. Bill set three National Records with these models. All used used his switch design. Each has been recognized by NFFS as a Model of the Year. Whew! That is a lot. Fortunately, Bill agreed to work with us in developing a switch based on his design concept.
- ALSO KNOWN AS THE LYNCH TRIGGER
The photo above and those on the linked page clearly show the design details as well as typical operation.
Operation of the switch is expected to be virtually failure proof. The "Safety Wire" locks the lever in the timer stopped position. When you are ready to launch, simply put your thumb (or any finger) on the lever. This action automatically kicks the safety wire off and all you do is let loose of the plane to start the timer. It is suitable for any launch style the owner prefers. Bill Lynch has used this design for over ten years without a single problem. Sometimes simple is the most elegant solution.
A typical installation method can be seen by clicking Here.
The switch can be used with any Texas Timer (except the MICRO I) as well as Seelig, Verbitsky style, or K-Mart type timers.
Dimensions: Length of faceplate - 1.38 inches. Width of faceplate - 0.38 inches. (35.2 mm X 9.5 mm)
Constructed primarily of INOX stainless steel for strength and durability
Loctite 242© used where appropriate
Supplied with plywood mounting plate
Weight - 2.27 grams
Typical working throw of lever used for timer interface - 11/32 inches (movement between on and off)
We have a hard time keeping these in stock. So, I suggest you do not put off ordering if you want any. I use it myself and love them.
Price: $30.00 each