RV-3 Plans - 'Clarifications'

[Ironflight]

I don't have the drawing number handy, but until I do, I'll plant this reminder post....

The drawing for the elevator push rods shows the rod between the stick and the bell crank to be 49 1/2" (ref). I ended up with 48 1/2"....so your mileage may vary, and that is why it is labeled as "ref". Don't be surprised if yours is a different length, and measure carefully!

Paul

[mmcdonald]

I started fabricating my instrument panel this weekend and the y axis dimensions on drawing 17 did not match the actual drawing.

Is 9 1/2" correct for height at center of the panel?

On drawing 17, reading from left to right, bottom to top, and starting at point (10,5.32) I believe the y axis dimensions should be:

5.32, 6.23, 7.04, 7.68, 8.19, 8.62, 8.95, 9.23, 9.4, 9.48, 9.5

I don't see how you could go up on the y axis and the measurement decrease? ie 5.32 to 5.23.

[Ironflight]

You're right Mark - the numbers on the drawing don't add up! I used the actual outline on the drawing -traced it on to thin paper and transfered that to the aluminum, and it worked out great. You can make the panel about 3/4" taller with the material Van's gives you - actually, you make the top the same height, you just let the bottom hang down an additional 3/4"....You want the "slots" for the longerons to be the same distance below the "top" of the panel (as on the drawing) to make the contours right.

Paul

[danbenua]

If you are making a tip-over canopy, you can ignore the plans for
the instrument panel top curve and just match it to the front bow
of the canopy frame. You will want to make the forward top skin
line up just below the top of the canopy bow. A strip of aluminum
attached to the top of the forward canopy bow overlaps the panel
and forward top skin to form a glare shield. This is shown crypically
in SK-54.

Also keep in mind that control stick must clear the bottom edge of
the panel. As you increase the panel height to fit in more stuff, your
stick must also get shorter. I'm using an Infinity grip in my RV-3B and
tried to keep the stick as long as possible while clearing the panel.

- Dan Benua

[Ironflight]

Originally Posted by danbenua

Also keep in mind that control stick must clear the bottom edge of
the panel. As you increase the panel height to fit in more stuff, your
stick must also get shorter. I'm using an Infinity grip in my RV-3B and
tried to keep the stick as long as possible while clearing the panel.

I was sort of worried about this when I made the bottom of the panel 3/4" lower, but when I installed the panel and the stick, I found that I had more than 3" of clearance between the top of the stick and the bottom of the panel. This was way different than my RV-8, where the stock stick hit the stock panel!

I ended up cutting about 1/2" off the top of our stick (on the -3) before mounting the Infinity grip, just because that is where it felt comfortable for both Louise and I. it helps to have cushions before making this decision.

YMMV (true of everything in a -3.....)

Paul

[mmcdonald]

Paul,

Thanks for backing me up, I will use the trace method and stock dimensions.

[danbenua]

This is a follow-up to post #2 in this thread.

A couple of years ago I recommended moving the flap inboard
rib closer to the fuselage by 7/8" to improve the linkage geometry.
This was based on careful measurements of Randy Lervold's machine.
Recently I was finally able to assemble my fuselage, wing, flap,
linkage, and fairing. To my relief it all fit just right!

The photo below shows the control linkage almost vertical, with plenty
of clearance with the F354 fairing. Also note the stiffeners and
rubber channel applied to the flap bottom skin to help it fair
smoothly to the fuselage tailcone when the flaps are retracted.
This yet another area that is a bit more complex than indicated by the plans .

[PeterP]

Hi Guys,

Not sure if I`m in the right place or not but here goes,
Fitting elevators to HS to drill horns for centre bearing, set rod ends to 3/4 to get 2" between spars but horn hits attach bolt on centre bearing bracket before getting enough down travel, increased rod end to 7/8 on inboard hinge but still restricts travel. Is it the plans or is it me. Looking for suggestions on what others might have done.

Peter Pendergast
Australia

[mvs163]

Hi Peter,
If I understand correctly, the flange of the steel horn hits the bottom AN3 bolt heads that hold the centre brg to the stab spar ?
My horns were RV 4 parts and oversize, I cut them down and rewelded one flange...as I recall.
I believe they were too long also, centre bearing to pushrod hole.
Mike

[PeterP]

Hi Mike,

You are correct, horns are bigger in every way. If I leave inboard rod end at 7/8 instead of 3/4 I get minimum control deflection, will think about a fix for that in time, will 4 1/4 to the push rod rod end be a problem?
I`ve built a couple of 7`s round hole round peg must be right but the 3 certainly has my old brain in overdrive.

thanks Peter