Firewall Forward V
12/18/2005 6 Hours
It was really cold at the hangar today. I was wrapped up too. I had ear plugs in for the noise of the heater, and my insulated winter boots on! I carried on with the front right floor of the baffles. These things take forever!
Here you can see how I had to bend this thing to get it close to the cowl inlets. I had to bend it so much that I couldn't make the outer angle out of one piece. If I bent the angle that far, it just cracked. I decided to do it in multiple pieces and add a 0.040" reinforcement piece to the outside. I tied all the pieces together with the bolt hole.
Here's a view from the other side...
Here's the reinforcement. It spans the full way forward. This should be OK I think. I've trimmed the bottom of the baffle side piece to be the same as the reinforcement, but I've not got a picture of that yet.
Next, I moved on to the exhaust stuff. I spoke to Chris at Aircraft Exhaust Technologies, and he said to ship it back and they'd tweak it some more. I can't say how great these guys have been to deal with. Unfortunately, I only took the one pipe in question home last week, and Chris said he needed the whole exhaust. This meant I couldn't ship it out last week. Oh well. While we were talking, he suggesting sorting out the heat muff locations so they could get that done too. Good idea! That's what I did next...
Here's the first heat muff. It looks like I can get away with the full size version here, as long as I go with the same type of muff with an offset centre. I marked the positions on the muff for the inlet and outlet. There's plenty of room around here for scat tube. It's close to the inlet pipe rubber, but I can reorient the clip so it's not rubbing, and movement is relative. It's also not as hot as the actual exhaust pipe, so I think this should all work OK.
Here's the second heat muff proposed position. Now I'm not sure if this is OK or not, being so close to the cylinder head. Maybe it will be. I'll see what Chris at AET thinks about it. I also need to allow enough room for EGT probes, so I need to figure out how far down the pipe these have to be. This muff needs to be alot shorter to fit, but it should still work out OK. It will also need to be the type with an offset centre. Basically the thin part of the muff will face directly forwards, and the outlet positions I marked accordingly on the pipe. Hopefully this is all OK.
Before I removed the exhaust, I took a bunch of pictures for AET's benefit. It will help show the configuration of everything. The main thing was to get a good shot of the system from below.
Here are some 3/4 views.
And a front view.
Look who's here! Dave is actually being put to work while he's here on 'vacation'. He's got some serious catching up to do! We spent the day today messing about with the baffles. Basically getting them all trimmed up to a point where we can almost get the cowl on.
We worked on sorting out the rear corner for the oil cooler. We're really worried about it cracking because of the weight of the cooler. We've also heard of a few horrow stories where it's actually happened. Well, it's not going to happen to us. We're beefing it up. Big time. Here we've pretty much got the left side trimmed to fit the cowling.
Here's the right side trimmed to fit the cowling too.
Here's the oil cooler position. Some reinforcement required.
We started drilling the doubler to the baffle. We still have to make a spacer and a reinforcing angle.
One of the mundane tasks that Dave has to do to play 3 years of catch up. Deburring!
Ouch! Darn those clecos clamps. It got me again!
Here's our reinforcement. We used 1/8" angle. We also ended up using a 1/8" spacer as the 0.063 wasn't anywhere near thick enough to clear the shop heads on the rivets for the oil cooler doubler. We added the brace too, but instead off joggling it over the angle, we put it underneath. Looks way nicer!
Here's a close up. We left the baffles at this point in favour of working on the wings. It was time to go home anyway. It's a short day, but a start at least.
