This page is under construction and needs some help so if any of you builders out there want to add an invention or technique to share, please send it to me at gdshs01@gmail.com

Iafret’s Solution to Unplugging

Dean’s Ultra Connectors

I will let the photos do most of the talking because it is so simple;

First, run out to your local auto parts store and buy an E-Ring tool. I got this one at Auto Zone for about $10.00 and it comes with three heads to allow you to get into difficult places if the connector is in the plane. (Saw one at Harbor Freight the other day for under $5.00)

The only mod needed to the connector is to drill a #50 hole in both sides of the connector system but be careful to drill so you miss both metal blades. I find if I nestle the drill into the radius at the surface level change it works very well.

Here are the photos to help you along.

This is the tool used to separate the  connectors with very little effort and a lot of control.

It has really helped to not be pulling on the wires and when the connector lets go, your had smashes a wing or some other vital part of your pride and joy.

Should be self explanatory, just drill a hole in each side for the tool to register with.

Looks and is easy

Dave Corven's Solution to Holding

Setup Templates Upright

Although these templates are for a Supra and available through Jack Iafret, you can build your own for any four servo wing. They are very handy to get both sides of the wing the same for all settings.

I usually use a surface plate and a height gage for initial setups, but this is much faster and probably of equal accuracy.

Here are the templates with their braces setting on a wing (not a Supra of course) to give you the idea of how they would be positioned on a compatible wing.

Testing A123 Cells Using the Medusa Research Analyzer Pro

This is an overall shot of the  test stand with the Thrust gage, Analyzer (Little blue box), motor and battery (the yellow stick behind the box and it contains 3X2200 mah A123 cells in series)

Here is a close-up of the Power system, in this case it is a Hacker B50 Carbon and 75 Amp Hacker/Jeti controller. The prop is a 18X10 CAM that I have used for a couple of years on this motor.

The system is capable of over 100 amps for a short burst (<20-30 seconds) but I normally run it around 70 amps to keep the controller alive. In 10 cell (NiMh) contests the unit will sink around 95 amps.

This is the output of the test rig displayed on my ancient laptop. What you are looking for is the voltage curve that goes from the upper left of the screen to the lower right. Notice how when the system reaches full throttle and holds for 5 seconds at the end of the curve, it continues to loose voltage. This is taking place while pulling about 65 amps (ave).

This is not like the NiMh I have used in the past as the same tests show that the voltage stays constant once max power is reached. In other words the curve stays flat for at least the time I tested it.

Not sure what will happen if I hold full throttle for 30 seconds and I do plan on doing that some day when I get time and can do it out of doors. Running this thing in the basement is kind of scary so I only hold full throttle long enough to get a trend curve.

A 2S2P pack of the same cells run at 90 amps with a different motor/prop/controller showed exactly the same characteristics but in that case each cell would be under only 45 amp load due to the parallel circuit.

What does this mean, not too much if the cells are doing well in your application but if you are looking for a very high current for a long period, these cells may not be the best choice unless you parallel enough of them to keep the current down per cell. I will still run them in competition at the NATS this year because of the pluses that they give. Very fast charge rate and low danger of flaming out on you. Also I do not plan on running them much more than 20 seconds under full load and they seem to do fairly well in flight tests, the sag is noticeable but it is at the end of the climb so not too harmful.

More testing some day.

To my club members, if you want to do some testing using this setup, let me know what you are trying to validate and maybe we can add some more information to our knowledge base.