Rear Battery Access hatch

[Ironflight]

I am one of those who believe that the battery works out pretty well in the aft location on an RV-8. The only little problem with this is that it's under the rear baggage compartment hat shelf, making access a matter of taking out about 20 screws - not an enjoyable task when crouched in the rear seat area. (This is not, however, a big deal if you use an Odyssey battery - you rarely have to go there!) I built my -8 with an external power plug, so I don't have to access the batteyr for charging or a jump start, but it is also a pain to inspect the elevator bell crank and pitch A/P servo.

At a recent fly-in, I took a look in the back of Danny King's "Beautiful Doll", and saw that he'd installed a hinged hatch, big enough to install or remove the battery. What a great idea! I took one picture, and from tat I duplicated the hatch on my own plane using some leftover aluminum scraps, hinge, and an extra Hartwell latch I had laying around. The Mod probably took me about 4 hour of work - well worth the effort for the access it provides. I found that I need to add some small aluminum angles underneath each edge of the opening to keep it straight, otherwise the hat shelf bows, and with the door flat, you have a little gap. I used some 0.040 aluminum I had for the door, which is thicker than the shelf material, so I needed to shim the flange down a bit to make the top surface flush. I also needed a thick piece of aluminum under the contact point for the latch as a "striker", and to bring the thickness up to where it closes tight. the pictures are pretty self explanatory, and my only question is why I didn't think of it when I was building....



Arrange the hinge so that the door can open fully and stay out of the way:


Size it so that you can get the battery out!


Looking up from underneath:

[Bill Palmer]

Thanks Paul and Danny,

Good Idea! Gives me something to do tomorrow!

Best Regards,

Bill Palmer
RV-8A Still In-Work
Chino Hills, CA

[chrispratt]

Here's some photos of how I did mine. I made one for my brother's -8 a the same time while the process was fresh in my mind.

Basic cut. You can use the cut out piece for the door or use a scrap piece of .032.



Trail fit. The hinge location takles some thinking so that the door will swing far enough out of the way.



Sand and fit. Sand and fit. Sound familiar?



Like Paul I added a stiffener to help support the floor. This is a piece of aluminum angle where I cut down most of the side that would hang down into the baggage area. I wanted this out of the way and I figure most of the stiffness comes from the bend area anyway.


Cutting the hole for the latch and fitting it is probably the most time consuming part of the job.



I used the edge of the stiffener to provide a good lip for the latch to catch on.



Here's how the configuration will look when done (without the clecoes obviously). I've got to start remembering to take pictures of the finished piece.



Hopefully this won't be needed often but I figure if I ever inadvertently run the battery down, this will make it easy to hook up jumper cables or charging cables without having to remove the entire piece.

Chris

[Ironflight]

Nice job Chris....so I know I copied Danny....but between you and him, who copied who?!

[chrispratt]

Originally Posted by Ironflight

Nice job Chris....so I know I copied Danny....but between you and him, who copied who?!

Paul:

Since Danny was finished long before I was, I must confess I got the idea after seeing his. He just works too fast for me to keep up. So Danny wins this one and hopefully will accept imitation as flattery.

Chris

[sf3543]

Instead of hinging the door and installing a latch, you could also use two pieces of hinge, on the left and right of the door, and just remove them to lift out the door. Similar to the cowling. Install the hinges so they are under the skin with two access holes on the front. It would probably be a little lighter than using a latch.

[Pat Stewart]

Paul,

Looks good, I also have a hatch in the same location however I made the door out of plexiglass. It not only allows quick access to the battery but I can also quickly inspect the battery, bell crank and autopilot servo and linkage with a flashlight without opening the door. I have also added a large door in the forward baggage compartment for easy access to the brake system without removing the baggage floor which is a pain. I also have a door on allowing access to the instruments however Im sure every RV8 owner has this mod.

Pat

[rv8ch]

This looks destined to become a classic RV8 modification. The best ideas seem obvious once you see them, and this falls into that category! Thanks for sharing it.

[cdmiller]

Paul,

Thanks for bringing up this subject and for the nice photos. Lots of good information in the thread. I'm going to have to do this next time I get into the baggage area to tweak things. By the way, what type of external power plug did you use and where did you put it? Any photos of that installation? I need to do that too.

Thanks for all of your posts on your RV-8 activities.

Dan Miller
RV-8 N3TU 355+ plus hours

[Ironflight]

Originally Posted by cdmiller

By the way, what type of external power plug did you use and where did you put it? Any photos of that installation? I need to do that too.

I'll have to search for photos Dan, but i used the Piper single-pole plug that Bob Knuckoll's has a nice write-up for (Check his web site). I mounted on the bottom of the fuselage, just to the left of my battery - a very short cable run (about 8 inches). Just put a doubler plate on the skin and you'll be good to go. I mounted the external power relay on the battery tray.

Many, if not most of the ideas I have used I have seen on, or have been inspired by, things I have seen on other people's planes - I try to give back to the community those things that people have given to me!

Paul