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  #1  
Old 01-16-2019, 12:34 PM
Girraf Girraf is offline
 
Join Date: Dec 2017
Location: Southern Maryland
Posts: 51
Default Elevator countwerwights

Am I supposed to be able to remove the counterwights from the elevators after its assembled? When I pre-assmble all the parts, my counterweights are so tight and locked in by the counterweight skin (where the two dimple dare for the bolts that hold the weight on) and the countersink I cut into the weight (to receive those dimples) that even with the screws removed, its not going anywhere.
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  #2  
Old 01-16-2019, 12:39 PM
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jmjula jmjula is offline
 
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Location: Portland, OR
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No. They aren't going anywhere due to the dimples as you mention, plus the outer nut is no longer accessible after assembly under the fairing. Don't bother removing any weight either, it is okay for these to be too heavy for flight (i.e. if not painted), but not ok to be too light (which can occur after painting if not careful) - this advice was from Van's to me during my build...
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Last edited by jmjula : 01-16-2019 at 12:45 PM.
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  #3  
Old 01-16-2019, 02:42 PM
tgmillso tgmillso is offline
 
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Location: Launceston, Tasmania, Australia
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Calculate the required paint weight (using recommended gsm or oz/sqft), then tape a weight in the middle of the control surface area to simulate this weight and size your ballast accordingly. This should get you pretty close. You can always take out further weight after painting by drilling into the side of the lead weight in the future, or you can add some nut plates now so you can add bolts and washers if necessary. I added two nut plates on each side, but did not need them in the end. Don't forget to account for the elevator trim system weight. The electric requires a significant amount of extra ballast. You're better off having a little extra now, then drilling to remove some in the future once you've finalized your paint. The most important thing is that if you fly painted or unpainted, you have the surfaces perfectly balanced for that flight condition so you don't get flutter. Another upside to painting before the test flight; you only have to balance once.
Tom.
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  #4  
Old 01-16-2019, 04:43 PM
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wirejock wirejock is online now
 
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Location: Estes Park, CO
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Default Counterweights

Quote:
Originally Posted by tgmillso View Post
Calculate the required paint weight (using recommended gsm or oz/sqft), then tape a weight in the middle of the control surface area to simulate this weight and size your ballast accordingly. This should get you pretty close. You can always take out further weight after painting by drilling into the side of the lead weight in the future, or you can add some nut plates now so you can add bolts and washers if necessary. I added two nut plates on each side, but did not need them in the end. Don't forget to account for the elevator trim system weight. The electric requires a significant amount of extra ballast. You're better off having a little extra now, then drilling to remove some in the future once you've finalized your paint. The most important thing is that if you fly painted or unpainted, you have the surfaces perfectly balanced for that flight condition so you don't get flutter. Another upside to painting before the test flight; you only have to balance once.
Tom.
As mentioned. Don't cut them. Easy to remove weight when the time comes.
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Donated 12/27/2018. Plus a little extra.
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  #5  
Old 02-11-2019, 03:39 PM
motodave motodave is offline
 
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Location: Littleton, CO
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I get that on the left trim tab side but would you leave the right side full versus the plans? I plan on completing the elevators with fiberglass tips while I wait for my fuselage kit to arrive in a couple of months... I waited too long to order the big box.

Dave
RV7 Slider
Littleton, CO

Last edited by motodave : 02-11-2019 at 03:43 PM. Reason: missing info
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  #6  
Old 02-11-2019, 03:54 PM
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RV7A Flyer RV7A Flyer is offline
 
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Quote:
Originally Posted by motodave View Post
I get that on the left trim tab side but would you leave the right side full versus the plans? I plan on completing the elevators with fiberglass tips while I wait for my fuselage kit to arrive in a couple of months... I waited too long to order the big box.

Dave
RV7 Slider
Littleton, CO
Backwards. Left side is full weight, right side is trimmed, just like it says in the plans.
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  #7  
Old 02-11-2019, 04:09 PM
motodave motodave is offline
 
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Got it... looking at Larry's reply I was left with the impression of his post to leave the right side un-trimmed as well. I jumped ahead and did not trim it before riveting the right side up. Should not be so bad to trim in place... I hope.

Dave
RV7 Slider
Littleton, CO
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  #8  
Old 02-11-2019, 04:25 PM
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wirejock wirejock is online now
 
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Default Counterweights

Quote:
Originally Posted by motodave View Post
Got it... looking at Larry's reply I was left with the impression of his post to leave the right side un-trimmed as well. I jumped ahead and did not trim it before riveting the right side up. Should not be so bad to trim in place... I hope.

Dave
RV7 Slider
Littleton, CO
Correct. Leave them. After paint, drill holes to remove weight. Right side with electric trim will probably be really close. Add the nut plates to the forward tooling hole in cse you need more weight. You can bolt in tungsten or lead washers.
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Larry Larson
Estes Park, CO
http://wirejockrv7a.blogspot.com
wirejock at yahoo dot com
Donated 12/27/2018. Plus a little extra.
RV-7A #73391, N511RV reserved (2,000+ hours)
HS SB, empennage, tanks, wings, fuse, working finishing kit
Disclaimer
I cannot be, nor will I be, held responsible if you try to do the same things I do and it does not work and/or causes you loss, injury, or even death in the process.
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  #9  
Old 02-11-2019, 05:15 PM
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RV7A Flyer RV7A Flyer is offline
 
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Quote:
Originally Posted by wirejock View Post
Right side with electric trim will probably be really close.
If he's building a *7*, the electric trim is on the LEFT elevator.
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  #10  
Old 02-11-2019, 07:21 PM
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wirejock wirejock is online now
 
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Quote:
Originally Posted by RV7A Flyer View Post
If he's building a *7*, the electric trim is on the LEFT elevator.
Doh!
The other right! Left.
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Larry Larson
Estes Park, CO
http://wirejockrv7a.blogspot.com
wirejock at yahoo dot com
Donated 12/27/2018. Plus a little extra.
RV-7A #73391, N511RV reserved (2,000+ hours)
HS SB, empennage, tanks, wings, fuse, working finishing kit
Disclaimer
I cannot be, nor will I be, held responsible if you try to do the same things I do and it does not work and/or causes you loss, injury, or even death in the process.
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