Firewall Forward IX
4/26/2006 5.5 Hours
I got to spend a fair amount of time at the hangar tonight, as I didn't have to go pick Lucy up from work. I got out of work at a decent time too!
I continued on with these bloody baffles. Man, I'm wondering how many hours I have in these things now. They seem to be taking forever. The other night, I left off just starting the left front inner wall around the gear ring. Tonight, I started with trimming it to match the left floor and the engine casing. Here it's all trimmed, and it fits pretty well. The 2"x4" spacer is working a treat!
Here you can see the gap that needs to be filled. I'm not too happy about it really. A bit more material would be nice here. Unfortunately, this is how it comes from Van's. I ended up making a piece of angle that attaches to the back side of the inner wall that also bridges the gap. I'll use some filler or something like that to bring it up to the same level as the rest of the baffle floor. Once it's painted, you'll never know. Unless of course, you've been reading my website confessions!
So here it is. Riveted and gap filled. I've also made the bracket that attaches the tops of the inner walls to the engine case.
A close up of the bracket. I had to relieve a fair bit to clear the cast engine case.
I trimmed the top of the left inner wall to the point where the cowling sits down properly. I still need to trim some more to get the right clearance. I'll do this when all the baffles are done. That way, they all get done at once. I managed to get the right inner wall trimmed to match the floor and the engine case this evening too. Pretty good progress for once!
4/28/2006 3.5 Hours
The other task I got done today was the right baffle inner wall. I made up the brackets that hold it to the floor, and riveted it all together. Things are moving along nicely now. These baffles are almost complete. Here it is installed on the plane. I still have to trim the top edges.
Again, there wasn't enough material on the baffle floor to reach the inner wall. Another place for some filler. The left side is exactly like this too.
My order from Spruce arrived today too. My standby alternator, and the special grommets for the spark plug leads to pass them through the baffles. I'll be looking at all that tomorrow.
4/29/2006 13.5 Hours
It was a seriously long day at the hangar today. It was so long that it's now the early hours of Sunday! Well I got a lot done today. The baffles are as good as done, apart from the seal material. I've decided to order some baffle fasteners from Aircraft Spruce instead of riveting it on. I think that the rivets look horrible, and using these baffle fasteners will make it look neat from both side, and enables the seal to be replaced if it get messed up somehow.
Right then.... I started off with the left rear baffle section. I made a doubler for the two grommets you can see in this picture. The big one is for the fuel line which will also have firesleeve on it, and the little one is for the cylinder heaters. I'm going to put the mains plug down in the lower cowling opening. You can also see the funky grommets from Aircraft Spruce. These are quite nifty, because they split in two so you can get the plug leads through the hole and then the grommet snaps back together and also covers the hole. Nice and clean.
On the same piece..... Previously, Clayton made the wedge piece you see here. Last week, he started to make the 'counter wedge' that will allow the bolt to stay straight. Today, I finished off his bits and trimmed them down some to lighten 'em up. Worked out lovely. Here you can see I also riveted them to the baffle. Trying to position these things in there and get a screw in the hole is nigh on impossible. If you secure these parts, it'll be so much easier to assemble/disassemble.
On to the right rear baffle section. I needed a hole for the ignition lead grommet, and also a hole for the FADEC harness. The small pilot hole above the crescent shaped doubler plate is where the FADEC harness will come through.
Once I'd got that far with the baffles, I started mucking about with the wiring. I threaded the ignition leads through, and also the FADEC harness to confirm fit and routing. Seems to be OK! Fantastic!
The coil/computer end of the FADEC ensemble. These positions on the firewall are working out well.
Now on to the front baffles. It was time to figure out the top edge trim, and in order to accomplish that task I had to do the inlet ramps on the cowling. Here, I've trimmed the inlets to match the lower cowling, and cleco'd the ramps in. Writing this now, I'm kicking myself, because I forgot to mix up some epoxy and stick them in before I left the hangar. Dag nabbit!
The ramps need trimming up a bit to make them look a bit nicer, but it will do for now for my purposes. To trim the baffles. Gotta... get.... these..... baffles..... done....
I put the cowl on, and used the little metal circle trick to mark a 3/8" line. This is the first of what seemed like a thousand iterations. For those not aware, the liitle metal circle trick is very cool, and very simple. Make a small circular shape out of some scrap sheet, that is 3/4" diameter, put a hole in the middle just big enough for your pen tip, and use it to space the pen away from the cowling as you draw your line. Easy. Well, maybe for a double jointed contortionist! Getting in through the cowl inlets can be quite interesting for you arm!
Eventually.... You'll have something that looks kind of like this. For my trimming, I had the green snips in my right hand, and my red snips in the other... Just call me Lobster Boy! The gap looks perfick.
And on this side too!
Here's the debris, all over the place. Lot's of curly bits of aluminium. Lot's and lot's...
Once I'd got the rough cuts, I took it all apart (AGAIN!) and cleaned everything up so it all matched properly and was smooth and proportional. What you're seeing here is a victpry for me over these baffles. They're finally done apart from the seal material. Here are some picks just so I can gloat.
T'other side....
I close up of the right rear wall.
And the left rear wall.
I can now breath a sigh of relief and start on the seal material. Once that's out the way, I can start on some fun stuff like getting the oil cooler on with the hoses, running all the engine wiring, fitting the standby alternator, etc. etc. All good stuff to look forward to, getting closer to the first engine start!
It's pretty late now, so I'm off to bed. I'm shattered. Oh yeah, there were no leaks in the brakes either after we filled them up last night! Sweet! G'night.
I managed some hangar time today, by getting out of work earlier. To get out earlier though, I had to get in at 6:30 am, which is hard for me to do as I'm not the best morning person.
I made two out of the three spacers required for the oil cooler. I couldn't make the third one, as I didn't have enough material. I've got some on order from Aircraft Spruce though. I had to put a bit of a flat on the edges of the washers that go between the flanges too, because I needed the bolts to be as close to the cooler as possible. The oil cooler reinforcement from Van's doesn't really give you much leeway with the holes.
Here's the cooler on the baffles. It's supported here by two screws. Now then, I'm not too impressed by the third inner fixing. It seems a little flimsy. I think I'm going to try to find a neat way to brace it a bit, otherwise it's not going to last very long. The last thing I want to be doing is pulling all this stuff apart in a few months time to fix it all.
I wonder if I can get away without trimming our cooler flange? The gap is a bit under a 1/4".
Now that the oil cooler is in position, at least temporarily, I can get on with some hoses. Finding a good routing for these was a bit tricky, because there's a lot of crap back here now! FADEC ECU's, plug wires, and the fuel line and prop cable has to squeeze through here too. What a mess! The braided line you see here is the oil cooler feed line from the engine. Since these parts move in unison, there's no real need for a bunch of slack. This was a fairly reasonable routing between everything.
It took me a bit longer to figure out that the best way to route the return line was over the top of everything. I was hoping to get it in between the engine mount, but it resulted in too short a hose length, and not quite enough flexibility to get to each fitting without putting stress on the cooler and it's mounting.
Here's the same hose from the other side of the plane. I had to use a 45 degree AN fitting coming out of the engine to miss the oil filter, then use another 45 degree adapter to make the hose sweep up and over the FADEC ECU. I'm wondering if the aluminium fitting will be OK in the engine there, or should I use steel? The fittings to the oil cooler are steel, and the 45 degree hose adapter is also steel. I took the oil filter off for this shot. I think I'm going to go ahead and order a steel fitting, just to be sure.
