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atalla

Well Known Member
I have a 2001 kit. some parts are not pre punched.

I will be placing an order to upgrade some of the Elevator parts to ease in building a perfectly straight control surfaces.

While making my parts list I noticed I have larger counterbalance weights than I'm seeing in the new plans.


Mine are rectangle and there is two per tip



I have heard that theres not enough weight on the elevators and ppl add some for final balancing. should i upgrade to the new style?

is this a safety concern? its possible a loose weight could jam in-between the HS and Elevator with the larger 2 weight systems.
Anyhow this is an easy change now a couple 713's and 714's counter weights an were done.

Thoughts?
 
I have the old style tail as well. Use your current parts. There is nothing wrong with them. No benefit to changing to the new style.

The lead can compress, so make sure the bolts have a good grip range by installing another washer if need be.

Don't make things harder than they already are. The old style is fine. ****, I even have the old rudder as well!

:cool: CJ
 
atalla said:
I have a 2001 kit. some parts are not pre punched.

I will be placing an order to upgrade some of the Elevator parts to ease in building a perfectly straight control surfaces.

While making my parts list I noticed I have larger counterbalance weights than I'm seeing in the new plans.


Mine are rectangle and there is two per tip



I have heard that theres not enough weight on the elevators and ppl add some for final balancing. should i upgrade to the new style?

is this a safety concern? its possible a loose weight could jam in-between the HS and Elevator with the larger 2 weight systems.
Anyhow this is an easy change now a couple 713's and 714's counter weights an were done.

Thoughts?
Click to expand...

I did the change to the new style on my RV-8 tail. IIRC, it saves 1.25 pounds per elevator. Saving 2.5 pounds of weight on the tail makes it worth it.

I purchased all new parts that were pre-punched. All I need to do was get the E-714 and maybe the E-713 plus the mounting hardware. The E-703 and E-704 are the same size as the non-punched E-603 and E-604. I took photos of the parts next to each other and can share the photos if you like. Would put them in this thread but need to head off to the hangar shortly because my wing kit is being delivered.

To correct any light weight on the left elevator because of the trim tab and servo, add a #10 nutplate to the tooling hole near the tip. One can then cut a square or round washer out of LEAD roof flashing sheet to balance the elevator to a perfect balance. I did this on both sides but only needed to add weight on the left elevator.
 
either or

The old style as stated above are just fine and I like them a little better as the fit can be trimmed nice a flush on both sides. The only thing that we do to balance out both sides is just drill holes in the back side of each weight tell we get them in trim. That way you don't see the holes on the side facing out and the airflow sees a nice flat surface as well. With them fitted flush with the web, you will not hit anything and should have about a quarter inch gap as per the plans. If you have not painted then you may want to leave them a little nose heavy tell you do. But it is not a big deal to unbolt them latter and stuff some lead plugs in the holes you drilled on the back side in order to get them in trim. Just what we did, Hope this helps, Yours, R.E.A. III #80888
 
RV6_flyer said:
I did the change to the new style on my RV-8 tail. IIRC, it saves 1.25 pounds per elevator. Saving 2.5 pounds of weight on the tail makes it worth it.
Click to expand...

This is significant. a bolt on 2.5lb savings Less weight but further forward=same effect.

I pulled the pin and ordered the parts. less than 70$ with the hardware

I'v learned these two things are generally very costly Horsepower up (HP) & Weight down (LB)

I think this will be a good bang for my buck upgrade
 
Old vs new parts

Here is an image showing elevator counterbalance parts that came with my early RV-8 kit (6XX series parts) that were not prepunched and the newest replacement parts (7XX series parts). The parts are the same except for the prepunch on the flange.

The change from the 6XX parts to the 7XX parts saves over 2 pounds per airplane.



I filed lead off the right elevator to balance. I then melted the lead and bolted it on with one of the screws that secures the left elevator with the trim tab and servo.
 
RV6_flyer said:
Here is an image showing elevator counterbalance parts that came with my early RV-8 kit (6XX series parts) that were not prepunched and the newest replacement parts (7XX series parts). The parts are the same except for the prepunch on the flange.

The change from the 6XX parts to the 7XX parts saves over 2 pounds per airplane.
<photos deleted>
I filed lead off the right elevator to balance. I then melted the lead and bolted it on with one of the screws that secures the left elevator with the trim tab and servo.
Click to expand...

Thanks for a factual post. I knew the use of counterweight at that distance from the pivot was more efficient, but this is pretty dramatic!! Is (do you know) this retrofittable from finished elevators?
 
The order left today. I'll use the old 603 tip ribs to close up the ends of the trim tab and the 605 to close up the elevator edge
 
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