Cowling hinges-bottom horizontal?

[Pmerems]

Fellow builders.

I am seeking first hand experience with per plans installation of the horizontal bottom cowl hinges on an RV-7A of 9A (don't know if 6A's are the same).

It appears from the drawings that it might be more than a little difficult to remove and install the hinge pins due to the fact that the exhaust tubes are right it the way.

For those who have built theirs per plans is there an issue? Would you repeat this installation again?

Any input would be appreciated.

Paul
RV-7A finishing kit

 

[Ironflight]

We essentially have the same things on the -8 as well. As you suspect, the exhaust pipes are actually in the way, however, the fact that they are hanging on flexible mounts allows me to push the pipes up just enough to pull those pins.

Many folks have had the hinge loops break, and use screws or camlocks there instead. If my hinge loops break, I might do the same thing (still intact at 425+ hours)...

Paul

 

[JACKR]

sky dynamics 4 into 1

Fellow builders.

I am seeking first hand experience with per plans installation of the horizontal bottom cowl hinges on an RV-7A of 9A (don't know if 6A's are the same).

It appears from the drawings that it might be more than a little difficult to remove and install the hinge pins due to the fact that the exhaust tubes are right it the way.

For those who have built theirs per plans is there an issue? Would you repeat this installation again?

Any input would be appreciated.

Paul
RV-7A finishing kit

Paul,
I have the Sky Dynamics 4 into 1 exhaust on my 7. No interference removing the pins. I do have a hole drilled in the pins and hinge so I can saftey wire them in place. This is the only exhaust I have had, can't compare to anything else, but do like it.

 

[robertahegy]

There is really no issue in removing the pins as they slide out above the exhaust pipes and are extremely easy to remove and install. I have not noticed any weakening or breakage of the hinge eyes or the rivets that hold the hinges on. Once the safety tie wire is cut, the pin is rotated about 80 degrees and withdrwn by pulling out and to the rear. Re-insertion is just a matter of starting the first eye and pushing it back in and safety tieing back to the lower cowl brace. I find the hinge pins a nice clean way of attaching the cowl and makes R&R ing the cowl a breeze.

The lower side and bottom hinges on my 7A are larger than the upper hinges and seem very sturdy. It seems odd that some people are having problems with these breaking. I guess time will tell for me. So far so good.

Roberta

 

[AlexPeterson]

The inboard hinge eyelets on mine busted at 700 hours.

I still use the hinge pins, but I removed the inboard 2" or so of hinge on both sides, and use some flathead screws there. Bolted little plates onto the firewall lip, and mounted nutplates in those.

It is very common to have these inboard hinge eyelets break.

BTW, I took a small round file to every single eyelet when building to remove the sharp, punched corners.

Let's see, that is about 2300 rpm x 60 min/hr x 700 hr x 2 prop pulses/rev = 193 million pulses. Roberta, does it still seem odd???

 

[robertahegy]

Yes!!!

Roberta

 

[RV8N]

We essentially have the same things on the -8 as well. As you suspect, the exhaust pipes are actually in the way, however, the fact that they are hanging on flexible mounts allows me to push the pipes up just enough to pull those pins.

Many folks have had the hinge loops break, and use screws or camlocks there instead. If my hinge loops break, I might do the same thing (still intact at 425+ hours)...

Paul

Mine are also intact after ~200 hrs. I usually lie on a creeper to remove these pins. If doing it again, I would probably put 3 quarter-turn fasteners on each side. This would simplify the removal of the cowl... just kneel on each side and turn the Q/T fasteners. Me like.

Karl

 

[RV7Guy]

Skybolts

Hi Paul,

I went with Skybolts on the top and seam between top and bottom. I also used them on the bottom, 2 on each side of the exhaust. I used hinges on the bottom cowl at the fuselage side. Doing it again, I'd use Skybolts on the entire thing.

If you go with the hinges on the bottom there is room to reach in and get the pins in/out around the exhaust.