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Elevator countwerwights

Girraf

Well Known Member
Friend
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.
 
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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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.
 
Counterweights

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.
 
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
 
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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

Backwards. Left side is full weight, right side is trimmed, just like it says in the plans.
 
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
 
Counterweights

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.
 
Yup, no issues my own decision not the posting. I wanted to mount the completed elevators on the horizontal before I made any trim decisions realizing I would likely need to adjust. Easier to remove weight versus adding more later. Thanks everyone.
 
It <is> possible to remove one of these after the elevator has been riveted. Don?t ask me how I know. :eek:
 
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