Archive for the 'Systems' Category

OAT and flap sensor

Thursday, November 23rd, 2006

I tried another round of panel labels. Zero successful.

I installed the OAT sensor in the left wing in the first full-sized bay. I would have put it further out, but the harness from AFS had a bit of a short OAT wire and I didn’t want to string another.

I also finished installing the flap sensor and attached wires to it. I moved the flap weldment up and down a few times with the motor and it seems like it’ll work well.
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Installed pitot tube

Wednesday, November 22nd, 2006

EAA 1440 meeting last night. I was elected VP for another year.

Back to the task of getting the wings finished up. I mounted the little circuit board for the pitot tube to one of the wing ribs. This would have been much easier a few weeks ago before the bottom skins were riveted. I bent the very end of the copper tubing from the pitot toward the wing root. I was still able to get the pitot tube in and out through the mast, but the bend made the transition to the plastic tubing easier. One a tip from DanC I used some silicone tubing from Spruce to connect the copper to the plastic. Seems like a very tight connection even without any clamps.
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I used an adle clamp to hold the plastic tubing away from the bellcrank.
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Label frustration

Sunday, November 19th, 2006

I spent most of the day trying to get the labels to stick to the panel. Out of the first batch of 5 labels, 2 actually turned out good. When they work, they really look great. There’s a small halo of glue around the labels, which I easily removed with rubbing alcohol.
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The next two batches were not so successful. It’s really frustrating to put an hour in on a batch of labels and have them all look great until the last step. They just don’t want to stick to the rough texture of the powder coating. In retrospect, I started spraying less glue on the panel for the later batches. Maybe that was part of the problem.

Out of 20 some labels so far, only 2 have worked. That’s not a good percentage. And I’ve burned maybe 6-7 hours on it. I wish there was another way to make great looking white labels, but I haven’t found it. I’ll talk to Frank at Pulsar again and give this method one more try. After that, I’ll use masking tape if I have to. I’ve burned way too much time on this.

In order to feel like I got something meaningful accomplished today, I asked Julie to help me drill the wing tips. They turned out quite good. There’s a 1/32″ gap in the middle of the top of one of the tips that I’ll try to reduce when I drill out to #30. Otherwise they turned out great and really nicely aligned with the ailerons.
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More labels

Wednesday, November 15th, 2006

Another round of label making. I contacted Frank at Pulsar for some advice on getting the white overlay to stick only to the toner. He said I still had moisture in the blue paper. I tried heating up the paper more with the heat gun before applying the overlay, and sure enough. Problem solved. Now I’m just having a problem getting the labels to stick completely to the panel. I tried cleaning the panel with rubbing alcohol and then lacquer thinner. No luck. I’ll call up Frank for some further advice after I review the instructions again.

Making the labels certainly has a lot of steps. I think I messed up a label at every step of the way, probably not helped by being tired and having a brew with dinner. I did get one word of one label to stick perfectly and it looks absolutely terrific. I just need to solve the problems with the last step and I’ll be on my way to label nirvana.

Here’s a JPEG of my labels so far. If you want the original Visio file, shoot me an email.
Panel Labels

Label making

Tuesday, November 14th, 2006

The panel is back from the powder coater. Looks great. It’s matte black with a slight rough texture. I tried making some labels for it using the Pulsar system. It’s a complicated process, but I think I have the steps down. If I were making black labels, it would be relatively easy. Adding the white foil is the main stumbling block at this point. I’m getting fuzziness around the letters and little white specks throughout the background. I’ll call Pulsar and see if they have some advice. I tried putting the label on a floppy disk as a test. The texture of the panel is very similar to this plastic. The missing parts of letters was just due to not using enough of the spray glue. That should be easy to fix.
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After messing around with labels for an hour or so, I was ready for something else. I bought a mini-switch from Digikey a while back to replace the one I bought from Radio Shack for the baggage compartment light. The RS switch just didn’t look very solid. I installed the new switch and put the cabin frame support cover into place.

Middle top skin riveted!!

Saturday, November 11th, 2006

Huge day. Julie agreed to some more riveting. I crawled inside the back of the plane and bucked the rivets for the middle top skin. Nothing tricky about it. It was actually much easier than the bottom wing skin riveting. As is the norm for tip-ups, I used MK-319-BS pop rivets on the forward-most 3 holes on each side. Looking more like a plane every day.
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Here’s a shot of how comfortable it is in the back of plane. “Sure honey take your time. I’m comfy.” I could have reached some of the rivets from the outside, but it’s easier to just crawl in there and get it done right.
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On top of that, I decided to make some more progress on getting the wings done and out of the garage. Luckily I just installed one Duckworks landing light, so this one was even easier. Cut, file, sand, drill, rivet, sha-zam.
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Long day, but a lot accomplished.

Top ignition wiring

Friday, November 10th, 2006

I stopped by Schucks, my most convenient and least favorite auto parts store, to pick up some doo-hickeys for holding the ignition wires apart. $5 seems a bit steep for a couple pieces of plastic, but it’s chump change in the grand scope of this project. Along with strategic placed adle clamps, the plastic things held the wires it perfect position. With that sorted out, I could put the connectors on the spark plug end finally. I followed the Emagair instructions a little too literally and cut the first wire right at the tip of the spark plug, which ended up being too short. I’ll have to re-do that entire wire. On the others, I allowed an extra inch of length which worked out perfect.
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Flap sensor wiring

Tuesday, November 7th, 2006

Spent some time figuring out exactly where I wanted the fuel flow sensor. The hose from the engine-driven fuel pump to the fuel servo looks like the best spot to me. I marked the hose and will send it out to get cut into two. I’ve agonized over this for hours. It’s a good feeling to finally have it decided. As long as I’m getting that hose altered, I’m going to get the hose from the firewall to the fuel pump shortened as well. The hose from Vans is simply too long and makes a real nasty bend. I’m going to get it cut down 3-4″.

Next sensor to deal with was the flap sensor. The wire in the AFS EFIS harness was way too short. Even if I ran it straight through the cockpit, it wouldn’t reach the flaps. Rather than put a connector in the middle, I yanked the wire from the harness completely and replaced it with a 22G wire all the way from the flaps to the EFIS connector. I also started on a bracket for holding the flap sensor. I’m doing something very similar to Larry Bowen, although altering it to work in the 7A.

While I was messing with the harnesses, I decided to move the wires connecting the GPS to the autopilot. Since the harness was pre-wired, I had to run the wire through the hole in the subpanel for the avionics. It was not ideal and has been bugging me for quite a while. It was easy to remove the pins from the autopilot connector, re-route the wire, and re-install them. Much better now.

Installed manifold pressure sensor

Monday, November 6th, 2006

Finally decided where and how to mount the manifold pressure sensor. I installed a couple of nut plates on the forward side of the firewall just to the left of the battery. I ordered some 1/4″ high-temp silicone tubing from McMaster to match the 1/8″ tubing that comes with the P-mags. That plus some polycarbonate T fittings made it all go together easily and cleanly. The fit of the tubing on the T’s is super strong. Nothing is going to pull those off. The sensor is a different story. I might use a mini hose clamp there along the lines of belt and suspenders. Also crimped the funky “WeatherTite” connectors on the wires from the EMS and installed the connector. Done and done.
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Just a few more sensor wires to go and that harness will be done. Not much wiring left at all–at least until the wings get installed.

More left wing riveting

Sunday, November 5th, 2006

Since the remote compass mount is pretty much done, I figured it was time to put on the top skin for riveting later. I soon discovered that I hadn’t painted the underside of it. The very forward part of the skin is visible inside the baggage compartment. It amazingly wasn’t raining, so I quickly scuffed, cleaned, dried, and painted. I later put the skin onto the fuselage with clecos. Looooooking good.

Julie helped me some more with the left bottom skin riveting. We were both pretty tired from Adele’s birthday party last night, so we didn’t get too far. One more session should do it. I put nut plates on the access holes as well.

I also messed around some more with the firewall forward sensor wiring, hooking up the fuel pressure, oil temperature, and RPM (to the P-mag output).