Firewall Forward

October 14, 2012

Firewall Forward Begins! - The Battery Box - 9.0 Hours

I'll tell you, at this stage of the project, the whole game changes. For a number of weeks now, I've been feeling kind of lost, spinning my wheels, very little direction and not really quite sure what I'm supposed to be doing now. My head is swimming with a dozen different plans, and I think about so many things that need to be done, I don't know what to do first, or which order in which to proceed. I've discovered I'm not the only one feeling this way at this point. When you're done with the Finish Kit, you're basically finished with Van's nice step-by-step directions. I've been on that path for so long, that now I'm suddenly feeling weaned, cut loose and on my own, and floundering around a little bit. Looking at other builders' sites helps some, but even there, there's not really a consensus or a clear pathway to the finish line. I've been doing some odd tasks, and a lot of reading, and things are finally starting to come together more and more around here. A few chats with some friends and with the guys at Vans have really helped.

Part of it is the realization that there ARE many pathways one can take at this point. It can be very confusing trying to figure out what's best. The good news, though, is the realization that all paths eventually lead to the same finish line. So it really doesn't matter if I jump into wiring and electrical stuff, finish the installation of everything in the aft fuselage so I can rivet that last top skin on and install the rear window, or work on the panel, or dive into fiberglass and wingtips, etc., or get into the firewall forward stuff. I've wondered, when's the best time to put the plane on her gear? Or hang the engine? I've even given serious consideration into painting the whole project NOW, before going any further. I know at least one local builder, well known who was an EAA technical counselor and built two award-winning RV's, who did just that. So while I was trying to figure out a game plan going forward from this point, and choose the particular pathway that's best for ME, here are a few considerations that led to my decisions.

Number 1, what do I have on hand that I can work with? Well, I can tell you what I don't have. I don't have any instruments, avionics, or equipment for my panel yet. I've been purposely putting those decisions off. For good reason. Look at how much technology has changed in just the last few years. Or even the last year. Have you looked at a new EFIS lately? Every time you turn around, things are being upgraded, replaced by newer better technology, etc. It looks to me like you take the plunge and buy all your panel items, and before you get it finished and flying, it's almost obsolete. I know you have to jump in at some point, but I decided a long time ago that outfitting the panel would be the last thing I do. So I'm not going to work on that right now. I don't want to work on fiberglass right now because the cowlings are a big part of it, and you can't do that until you can fit them, and you can't fit them until the engine is installed. Obviously I'm not ready for any of that yet. These are just some examples of what's been running through my mind.

Most recently, I thought I had a pathway all figured out. I was planning on finishing up the electrical stuff in the aft fuselage, at least, so I could rivet on that last skin, install my rear window, and then move forward and put her on her gear, and then hang the engine. As I got serious about doing all of that, in that order, I realized I really need an education when it comes to electrical stuff. I don't know anything about it. Plus, I need to know what kind of EFIS I'm putting into my panel, because there might be an ADAHRS and/or some other equipment that needs to go in the aft fuselage. I would need to install antenna's, but I don't know what radio(s) I'm going to have, or how many I'll need, what kind of wiring to do for it all. Where do the GPS antennas go? I've seen some under the cowl, some on top of the aft fuse, some on top of the glareshield under the windshield. I'm just going to have to learn more first. I'm not ready now to make those decisions.

So what else can I do, and what do I have on hand? Well, I've recently finished putting my wheels, tires, tubes, and brakes together, anticipating the day when I put her on her gear. I also have this beautiful engine sitting here on a pallet on the floor. The more I see winter coming, and looking at it sitting there, I can't stand it. I want to see this engine on the nose! This is something I can do, it's here staring me in the face, so I'm going ahead with some firewall forward work.

Having made that decision, I studied Vans Accessories catalog. Particularly, the firewall forward kit list of items. I don't have money to get it all right now, but I don't need it all right now. I can drive over there and get stuff whenever I need to. So I put together a list of a few things I can get right now to keep me busy for a while. Then I drove down to Vans and picked up a few things to get me started. Basically, I'm working on getting all the stuff that goes on the firewall in place so I can hang the engine. The order starts to become clear. You can't hang the engine until you have the plane on her gear. You can't put the gear on until you have the engine mount permanently installed on the firewall. And you can't put the motor mount on the firewall until you install a few items first. So... here we go. I bought the Firewall Forward Documents, Plans and Drawings. I also bought a battery box, and some electrics that bolt to the firewall.

Once the FWF plans/drawings are in hand, things suddenly start to clear up in your mind. A lot of questions get answered. So the first thing I'm starting with is the preparation of the battery box. There are two battery options to choose from. Most go with the Odyssey battery, which is what I decided to do as well. It's smaller, lighter, less expensive, and seems to be the superior option. Here's the kit for the battery box, as it comes from Vans:

The plans are straightforward. I dove right into this, this is stuff I know how to do! And it's fun! Well, at least it is until you realize this box is powder-coated steel. A far cry from aluminum. The plans call for some optional lightening holes, and this material is a bitch to work with. I read enough horror stories about trying to do this with a hole saw. Or a fly-cutter. I was reluctant to try either one of those options. Well... there happens to be a used tool shop right around the corner from my home. It's called "Ted's Tool Shed". This old guy has been in business there for over 40 years. It's kind of like a flea market every day of the week. You can buy or sell stuff there. I decided to take my chances and see what he might have to help me out. You wouldn't believe how many times I've found bargains there. So I went in and asked if he had any knockout punch tools. He scrounged around and found a box full of misc. stuff. He just handed it to me to sort through. So I dug through it, and look what I found! He had some genuine Greenlee knockout punch tools, complete with a ball-bearing-equipped bolt. I found a 2-inch size that I needed for this battery box, as well as a 1-1/8" size for firewall penetration points for wiring. Grand total? $10.00 You read that right... a mere $5 each! These tools are like new, and they really worked like a charm on this box. Seen below is the finished battery box, after all the usual drilling, dimpling, countersinking, riveting, and painting. I was able to reach all the rivets with my squeezer, thanks to all those holes. When it was finished I painted it with Lycoming Gray to match my engine. You can also see the steel slugs punched out in the process of lightening this up. It did take some significant weight off of this thing!

The holes on the ends aren't called for, but since I had the smaller punch, what the heck. I added a pair of holes on each end as well. It was easy and I'm really happy with how this turned out.

I also spent some time on the firewall work, although I don't have any pictures of it. I'll have some soon. Basically, there are some rivets that need to be drilled out and the holes enlarged for the bolts that will hold this box to the firewall. So I did that, drilled and countersunk for nutplates, and riveted the nutplates in place on the firewall. This was more work and time than I would have estimated, but it's good to have it done. I could bolt this to the firewall now, but it would be in the way for what's next, so I'll wait.

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