Barry
I don't know how valuable 1/4 motor testing will be on an A6 but the technique is the same for any model. Measure the distance from hook to hook on the model. Make a dummy motor ( a stick with a hook on each end) that is 3/4 of the hook to hook distance. Make a rubber motor that is the thickness of the motor you plan to use and 1/4 of the length of the full motor. Weigh the quarter motor and then ballast the dummy motor so that it weighs 3 times what the quarter motor weighs. You want to arrange the ballast on the dummy so that the CG of the dummy is at its midpoint.
I use a closed wire loop on one end of the dummy and hook that end to the rear hook on the model. The other end has an open hook to hook to the motor. Use one o-ring on the front of the real motor and none on the back.
For winding hook the closed hook on the dummy to the torque meter and hook the plain end of the quarter motor to the open hook on the dummy. The o-ring end of the quarter motor goes to your winder. Wind the quarter motor to the same maximum torque as a full motor. Back off turns to reach the launch torque you want to try. Launch the model and record the flight time and the maximum height it reaches. These numbers should both be 1/4 of the time and height of a full motor flight.
For an A-6 I would probably do half motors instead of quarter motors. The technique is the same. Here is a half motor setup for USIC:
Full motor to try - 18" .050 thick 1.0 grams
Half motor - 9" .5 grams
Hook to hook distance - 5 1/2"
Dummy length 2 3/4"
Dummy weight .5 grams
The full motor I used was good for 9 minutes and 3rd place behind Tem Johnson at 10:05 and Emil Schutzel at 9:50. Both of them were well out of reach for me and my model on that day.
----- Original Message -----
From: barrysholder
To: Indoor_Construction_at_yahoogroups.com
Sent: Wednesday, June 10, 2009 11:43 AM
Subject: [Indoor_Construction] short motor testing
Can someone give me the technique of the 1/4 motor testing for an A 6. I want to do a little flying at my wife's school gym which is probably only about 20' my guess.
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Received on Wed Jun 10 2009 - 09:21:46 CEST
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