More aileron and wing spar work
Tonight I installed the doublers for the hinges on the wing and aileron spars. I also got the corner braces done on the aileron. The spar splices now have the plywood doublers installed as well.
I had the aileron turned around on the table when I started gluing parts. Since I didn't notice it was flipped, I installed one set of hinge doublers on the wrong end. Not a big mistake, but annoying none the less. The next work on the ailerons will be to install the missing hinge doubler and the remaining trailing edge plywood strip. At that point, I can install the hinges and start working out some other details for the cove supports. Getting closer to having one wing done. The other wings should go pretty fast, since I can skip the head scratching part.
Aileron progess
I was able to remove the clamps and then glue on the leading edge last night before bed. I did a little clean-up today of epoxy drips and also some sanding. I need to do some work on the wing to be ready to get the hardware setup. Then I can sheet the LE of the aileron and wrap up the details.
More aileron construction
I spent a couple hours tonight working on the first aileron. I got the hinge doublers, spar cap strips and one of the plywood trailing edge pieces glued. Lots of clamps.
Next will be the leading edge, corner braces and the other piece of plywood strip for the trailing edge.
Exhaust tunnel progress and first aileron out of the jig.
Lot's of work got done today. This morning I pulled the aileron out of the jig. It looks good and stayed straight. The trailing edge has a very slight rise in the middle, but that should be correctable when I install the TE plywood. More pictures here.
I got out to the hangar this afternoon and started hacking on sheet metal for the exhaust tunnel. I came up with a plan that had few critical bends on any one part. The width of the middle tunnel piece had to have the right angle and be pretty close to right width. I left some length on the part so that it could be slid forward or backward as needed to tighten up the fit with the two side pieces.
This all worked out much better than I had hoped. I was expecting the first parts to be 'practice' parts, but they are looking good enough to keep. There is more work to do trimming and fitting some of the edges. I also need to get the hardware installed. I got most of the hardware done for the two side parts, but the tunnel is only mounted with a couple clamps right now. More pictures here.
Glued up first Raven aileron
Today I built up a jig to glue the aileron spar, ribs and trailing edge stock. I got everything glued and clampled without any problems. I'll pull it out tomorrow to see how it looks.
I used some scrap wood to build some edge clamps on the fence of the jig. This allowed me to keep all the trailing edge stock and the back of the ribs located in the same plane and not buckle up. I also used a block to clamp the trailing edge lengthwise in the jig. Simple stuff, but seemed to work well.
First mock-up of the exhaust tunnel
I did some quick fitting of poster board to the exhaust tunnel tonight. I think this job will get interesting. It looks like it will be tough to get this sealed up and looking nice.
I also cut off the remaining landing gear attachment points for the old gear. The old battery mount and the front belly former were also removed. I needed to get those out of the way to get started on the exhaust tunnel sheet metal and new battery mount for the PC680.
Here's a picture of the poster board work.
Starting Pitts exhaust tunnel work
The new Wolf Pitts gear will allow the exhaust to be tucked up under the belly of the Pitts a little better. Part of making this work requires building an exhaust tunnel. Today I started taking a look at what will be involved. There is a steel former that located the front of the forward belly pan. This will need to be replaced with a new piece that has the cutout and new profile for the tunnel.
I taped a couple of welding rods in place to roughly represent the new edges of the tunnel. This will help me start thinking about the details and get a better picture of what the end result should look like. First, I'll cut out the old former. Then I'll get some poster board to start mocking up the sheet metal. Once I've got a good layout and plan, I'll make the new former and start bending some sheet metal. I'm guessing that this will turn into a fair amount of work to really get it right. We'll see soon enough.
Here's a picture of the area looking back from the bottom of the firewall.
Wolf Pitts engine mount and gear
I spent some time today working on the fit of the engine mount. My bolt pattern on the front of the Pitts fuselage was slightly non-standard. This caused a slight misalignment after it was modified by Wolf Aircraft for their rod landing gear setup. Tony called me up when he noticed the problem in his jig and had me measure a few things on the fuselage to confirm. When I got the mount back, the bottom left bushing on the mount was about 1/8" off from the bushing in the fuselage. The other bottom bushing was a bit tight as well.
I drilled and dug out the old bushing in the fuselage and replaced it with a new one with the correct alignment. I got as far as getting it fit and installed with a couple large tack welds. Almost all of the binding on the bolts is gone now. It is easy to install and remove all four bolts. I'll get the mount bolted up and back on the gear to do some sanity checks and when everything checks out, I'll do the finish welding.
This is good progress. I thought it would be more difficult, but it went as planned and was easy to do. Soon I'll be able to move on to the other fuselage details needed before it can be media blasted and painted or powder coated.
I also put in an order with Aircraft Spruce for a bunch of aileron hardware and wood needed for the new wing mods. I should be able to make some good progress on the wings over the next week.
Started Pitts aileron layout
I started working on the layout for the Raven ailerons. There are several things that need to be worked out and decided before I start drilling holes for hardware and building the ailerons. Tonight, I started on the hinge placement. I'm planning on moving the slave strut behind the I strut, so I started with the center hinge. There is quite a bit going on there with the bellcrank, drag wire, hinge, slave strut horn and aileron horn. I replaced the old bellcranks with new Raven Aircraft parts that will clear the brace wire.
The tip hinge is easy. Since I'm going to box in the wing tip, there is really only one place for it to go. I'm still thinking about the inboard hinge location a bit. It will sit close to one of the drag wire support blocks. I'm not sure yet how much clearance I will give there. The outboard end of the ailerons will be boxed like the main ribs, but I'm not sure how I want to finish the inboard ends yet. I'm leaning towards boxing them as well, but that is up in the air for the moment.
The Raven kit and hardware are top notch. It makes it much easier to figure this stuff out when you're starting with nice consistent parts.
Here's a shot of the lower right wing with the aileron ribs and spar clamped up to the hinge hardware. Nothing is installed, drilled or glued yet.
Some progress today
I made and installed the new lap belt attach fittings. When I added the Hooker harness with double lap belts a couple years ago, I made an attachment that was too high and forward compared to the seat. Because of this, the non-ratcheting belt almost runs out of adjustment with me in the seat. The new attachment location should fix that.
I also got the gear legs painted so they wouldn't start rusting. Pictures in the Rebuild gallery.