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flyingfool
 Post subject: Electric vs. manual trim
PostPosted: Mon Aug 29, 2016 5:58 pm 
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If building new, is it really worth the trouble and expense to go with electric elevator trim?

Do you save much or any space in the tunnel?

I tend to like manual from as my experience with electric trim is that I either have too much or too little and find it hard to get the exact trim I want. With manual it just seems more infinite adjustable and I have more "feel" to adjust the trim.

Which is lighter: manual or electric?

I do plan on electric flaps to safe the tunnel and comfort space. Also I plan electric aileron trim because I don't know how to really make aileron trim manual that is effective.

Maybe this year at KY Dam I will have to fly and feel how others have their electric elevator trim set up. If I'm going electric for the rest I may as well go all the way!

By the way, my wife IS coming to KY Dam this year! Can hardly wait.


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Ryan Allen
PostPosted: Mon Aug 29, 2016 6:19 pm 
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I just recently made the switch to electric pitch and roll trim. I like it better than the manual trim for both axes.


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Hagle347
PostPosted: Mon Aug 29, 2016 8:06 pm 
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In the past it was more difficult to find the exact motor to give the right proportion. If you use the Dayton geared motor for electric elevator trim, I think you'll be happy with the result. Another consideration might be how you intend to actuate the motor. 66WT has a panel mounted switch to move the motor. 218TH will have a coolie hat on the stick connected to relays then to the motor. I am happy with the result on WT - 218TH....I'll let you know next year.


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jrevens
PostPosted: Tue Aug 30, 2016 1:50 am 
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Like you, I prefer the manual for most of the same reasons. There are pros & cons. The electric set up will be heavier I believe, and the extra weight is all in the tail. Not a big deal though on the Thorp. I didn't find the right angle drive I used, or the 1/4" drive tube to be any issue for me - it does take up a little room in the tunnel.

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Arvada, Colorado

T-18 N71JE (sold)
Kitfox 7 SS N27JE


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Rich Brazell
PostPosted: Tue Aug 30, 2016 5:12 pm 
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I believe you will find if the speed of the trim motor it too high it will be difficult to get that "sweet spot." ??? You only need a small movement of the trim surface to get the desired results . Small movement , slow trim speed . A too high of an RPM you will overshoot the desired trim . I am always wrong at least 50% of the time ! :P

RB O0
BaBaLu


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david read
PostPosted: Tue Aug 30, 2016 9:49 pm 
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Although I definitely see the advantages of the simplicity of the original design I have to say I like my setup. I moved the rudder cables outboard and put the flaps and pitch and roll trim all on the stick. That leaves nothing in the tunnel but the stabilator push pull tube. I made the rounded tunnel clear the tube by 1/4" at its highest point of travel and the sides giving the smallest possible tunnel. Thus a little wider seats and the tunnel sticks barely above the seats. It makes for a significant amount of extra room, worth the effort as long as you don't have to scrap any work you have already completed. My two cents.


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Rich Brazell
PostPosted: Tue Aug 30, 2016 10:16 pm 
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David : That is the way to go ! ;) If I had it to do over that would be 1st on my list no matter how much work it took . ::)

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jrevens
PostPosted: Wed Aug 31, 2016 1:11 am 
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I'm with you, Rich... I like what David did very much, and I'd definitely copy that if I was going to do it again (maybe in another life!). Right now I'm workin' on trying to make a nice Kitfox.

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John Evens
Arvada, Colorado

T-18 N71JE (sold)
Kitfox 7 SS N27JE


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