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How to trim a model

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Old 04-26-2008, 08:01 AM
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karolh
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Default How to trim a model

Could someone kindly give me a link to any good " How to trim a model " article. Thanks.

Karol
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Old 04-26-2008, 08:13 AM
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Scar
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Default RE: How to trim a model


ORIGINAL: karolh

Could someone kindly give me a link to any good " How to trim a model " article. Thanks.

Karol
From IMAC:

http://www.mini-iac.com/EditModule.a...View&ItemId=27

From an NSRCA site:

http://www.rcaerobats.net/trim_chart.htm
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Old 04-26-2008, 09:55 AM
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Default RE: How to trim a model

If those don't drive you nuts - you have the patience of Job.
Trim Charts -wer originated by those trying to arrive at the "perfect model" which literally flew it's self thru various attitudes .
Once this is all perfect - try flying it in a wind -
you will likely find that you MUST fly the model constantly as the perfectly nuetral model has directional stability problems.
But go thru the exercize - it is a good learning experience
when done - find the setup comfortable for you
typically a slight forward balance to encourage directional stability will suit most setups.
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Old 04-26-2008, 12:36 PM
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karolh
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Default RE: How to trim a model

Dick,

Thanks for that insight as I will certaintly try to achieve a position that I am most comfortable with.

Karol
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Old 04-26-2008, 12:51 PM
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Default RE: How to trim a model

What sort of model are you trying to trim out? A trainer requires a more forward balance point than an aerobatic model in order to be more stable for a new pilot.

EDIT- I just went to Google in put in model airplane trimming and got back a lot of good looking hits on the first two pages of listings. Two of them were the links above. Some others were more for general and training style models and they all have something to offer. Do the same search and read through those pages.

Also check out the links in the sticky threads at the top of the listings on this Aerodynamics forum as well as the Scratch Building forum for links to sites with information and calculators to help you determine your CG location.
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Old 05-02-2008, 04:06 PM
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Check out this link. This is an article written by Bryan Hebert and myself (mostly Bryan, I just translated for those who don't speak coon-*****). Bryan's models are some of the best-flying airplanes I've ever seen... neutral in all apects of flight. [link=http://hebertcompetitiondesigns.com/interest.htm]Triangulation Trimming[/link]
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Old 05-03-2008, 12:45 PM
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Default RE: How to trim a model

That's an excellent article and thanks for the link.

Karol
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Old 05-03-2008, 01:05 PM
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Nathan King
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Default RE: How to trim a model

Those articles are good, but there's one thing I will add. Most people think trimming is a one time deal, but this is simply not so. I have airplanes many years old that I still tweak a little here and there just to get that seemingly elusive 'perfect' feel. Most people don't realize just how misadjusted their airplanes are until they fly something that's been painstakingly set up. Even my old trainer feels really 'locked in' after I took the time to make those almost imperceptably small adjustments.
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Old 05-08-2008, 01:57 PM
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karolh
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When I use to fly 40 size glow models, apart from doing a CG check as per the plans all model trimming was done via the Tx trim tabs for level and straight ahead flight. Now that I have progressed to flying larger models and now know the benefits of proper flight trimming I realize that it is essential as a well trimmed model is a joy to fly.

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