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Normal Topic Jig for test CG for your models (Read 635 times)
alfakilo
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Re: Jig for test CG for your models
Reply #3 - Jul 3rd, 2018 at 6:31am
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Those are pretty spiffy, but for me, your idea works just as well and is easier on the pocketbook. Besides, I bet we all get more pleasure out of working these things out ourselves rather than relying on commercial gadgets.
  
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Sky9pilot
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Re: Jig for test CG for your models
Reply #2 - Jul 2nd, 2018 at 3:48pm
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Many model aircraft hobby companies offer CG machines.  Here's a couple pictures of some... around $15-$30  1. hobby king  2. great planes
  

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If God is your Co-pilot...switch seats...
Your attitude will determine your altitude!- John Maxwell
And ye shall know the truth, and the truth shall set you free. Jn 8:32
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alfakilo
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Re: Jig for test CG for your models
Reply #1 - Jul 2nd, 2018 at 1:41pm
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Very nice tip! I'll do exactly this for now on. Thanks very much!
  
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Sky9pilot
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Jig for test CG for your models
Jul 2nd, 2018 at 10:34am
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Alfa asked about how to test and set cg on our models.  Here's a drawing of a jig I've made to hold the model as CG is being set/tested. I hope the drawing is self explanatory. It rests on the the table top and allow the model to sit on the jig between the dowels.  If CG is marked on your plan, measure the distance from L.E. to CG and then mark this distance at the wing roots on each side of the model and let the eraser tips rest on this spot and add weight to nose or tail to get the balance you want.  I usually balance with a bit of nose down attitude on the jig.

A neat trick for low wing models is to turn the aircraft upside down so the fuselage is hanging below the wing.
« Last Edit: Jul 2nd, 2018 at 3:50pm by Sky9pilot »  

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If God is your Co-pilot...switch seats...
Your attitude will determine your altitude!- John Maxwell
And ye shall know the truth, and the truth shall set you free. Jn 8:32
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