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What did you do on your airplane project today?

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Marc W

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Mar 31, 2017
Messages
628
Location
Colorado
I removed the baffles and the Diehl accessory case from the VW engine today. Getting the baffles off turned into a project. I won't use as much silicone to seal the pieces together next time!
 

Toobuilder

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Jan 19, 2010
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5,037
Location
Mojave, Ca
Changed tires, playing with wheel alignment, added a "viscosity valve" to override my vernatherm, and added a piccolo tube to the cooling plenum so I can compare ram pressure to the induction airbox.
 

Victor Bravo

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Jul 30, 2014
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8,420
Location
KWHP, Los Angeles CA, USA
Fabricated a new sheet metal tray for my GPS tablet, wrestled with figuring out how to mount it in another part of the panel (1956 C-172), won the wrestling match, and painted it flat black using VHT hi-temp engine paint. Figured I'd take advantage of the VHT's curing capability (po' boy's powder coat, don't you know), so I brought it home after the paint was dry, and proceeded to heat-cure the VHT paint per the instructions.

Unfortunately, not only was the wife moderately unhappy with the idea of re-purposing the toaster oven/air fryer for this purpose, but then she rather loudly decided that heated paint curing fumes was in fact not an acceptable type of potpourri.

I tried to tell her just how important a scratch-resistant, fingerprint-resistant tablet tray was, in the grand scheme of airworthiness.

I'll report back to HBA as soon as the doctor removes the rolling pin from my skull.
 

Merlin

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Nov 17, 2020
Messages
43
I'm still in the design phase, i decided to drop the wood spars and use aluminum tubes instead
 

Pops

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Jan 1, 2013
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8,800
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USA.
Finally did some airplane stuff today. Most of 2020 was devoted to correcting and upgrading wiring in the house, shop and shed. Then installing the wife's solar electric system. I got that all signed off before Christmas and then rehung my gas heater in the shop. I had to take it down for the solar system because the old vent went through the roof where the solar panels mounted.

So I have heat in the shop again! I finished exhuming my big work bench this morning(I haven't seen the top of it in a while) and got my engine on the hoist and drained the oil today. Tomorrow I will start disassembling the little VW. I am going to do a complete teardown and inspection. I need to have Pops fly out here to supervise! I have room in the hanger for the SSSC, extra bedrooms and plenty of food. Nothing to stop him!
Thanks, but the rope my wife ties around my neck is to short.
You can do it, I know you can.
 

gtae07

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Joined
Dec 13, 2012
Messages
2,075
Location
Savannah, Georgia
In the last couple days:
Final installed aux alternator, mag hole covers, coil pack mounts
Tried to install governor but the studs are too short (longer ones on order)
Fabbed ELT antenna doubler
Installed transponder bracket
Ran pull strings for ELT and OAT probe wires
Fabbed com radio mount
More 3D tetris with avionics boxes
Finishing touches on the panel layout, so I can send it for laser cutting next week

Would be nice if I had all my wire, but it's been sitting in the UPS facility since the 21st
 

Rockiedog2

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Dec 11, 2012
Messages
2,559
Fab'ing up fuel and brake lines before riveting fwd fuselage skins on.

For those "professionals" that look down on all us poor hobbyist for using too many clecos, I'd like to point out the skillfully placed lower forward baggage bulkhead....


Just realized something. My 8 was a QB and I remember what a job it was running plumbing in the gear towers. The skin was on the fuse so had to work thru those little holes. No hide left on wrists...yours is of course no problem.
 

Toobuilder

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Jan 19, 2010
Messages
5,037
Location
Mojave, Ca
Did some instrumentation and flight test today. I installed a piccolo tube in the upper deck of my cooling plenum and a pressure tap in my induction air box. I tied the two together with a hastily made water manometer, and used some hair dye to color the water. I wanted to find out if there was any pressure difference between the "optimized" pitot style induction air box and my cooling plenum - both of which have proven to be very effective at their respective jobs. I am trying to decide if I keep the external induction pitot (and the increased wetted area/drag), or shave the scoop off and harvest cooling air for induction.

Did one test flight today to get an idea of the differential between the two pressure sources. As it turns out, the differential is about 6.4 inches of water and scales with speed (the wheel pants and gear leg fairings we're off for this flight so I could only manage 180 KIAS). The induction air box is developing more pressure than the cooling plenum by a noticable degree on my manometer. Some quick conversions show this to mean that I can expect about a half inch loss of MP compared to what I see today. This is about 6 HP on my engine if I'm looking at it right.

Still some more testing to do to see if I can close the gap some - but then I still need to see if the loss of HP more than makes up for the drag reduction.

Fun stuff.IMG_20210103_132751777.jpgPiccolo resize.jpg
 
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gtae07

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Joined
Dec 13, 2012
Messages
2,075
Location
Savannah, Georgia
Installed com radio bracket
Cut and drilled com antenna doubler
Fabbed main bus fuse panel mount
Fabbed a brace for the ADAHRS mount Relocated engine bus diodes so the wires can reach them properly
Got the studs out of my prop governor adapter (it needs longer ones)
Yet more 3d tetris...
 

Marc W

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Joined
Mar 31, 2017
Messages
628
Location
Colorado
I pulled the heads and cylinders off my VW today. I kept the pistons in the cylinders. One cylinder has two deep parallel scratches running lengthwise. I suspect I have a broken ring. I got interrupted by phone calls so didn't get the piston out to see if the ring is broken.

The brain trust here said my oil leaks were due to pressure in the crankcase and a broken ring could cause that. I will find out tomorrow. I don't know why a ring would break.
 

n45bm

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Joined
Feb 20, 2019
Messages
71
Location
Seguin
I ran wires from the wingtip nav lights/strobe to the landing light area, located the aileron push rod in the right wing and messed with the aileron push rod length and adjusted the rod end bearings to proper length. This is from the bellcrank to the aileron horn. All this is on the Arion Lightning project I'm trying hard to finish, or at least make progress on.
 

Marc W

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Joined
Mar 31, 2017
Messages
628
Location
Colorado
I got most of the VW disassembled today. The timing gear and the rods are still on the crank but everything else is apart. The main and cam bearings are speckled with embedded metal chips and the main journals are rough. To be expected because the original builder stuck a valve in the engine while running it in his driveway. The head of the valve broke off and the piston hammered the valve stem through the top of the head into the rocker box. He got a new piston and cylinder and different heads and bolted it back together. He told me about this and gave me pictures of the damage when I bought the plane. My mistake was that it never once entered my simple mind that somebody would blow up an engine, stick new parts on it and not at least change the oil. He kept running it with the dirty oil and I bought it and flew it a couple hours before I changed the oil. It was full of metal particles. The screen caught the big chunks but there were plenty of smaller pieces that went through the screen. It didn't have an oil filter on it when I bought it. I have since put an oil filter on it and everything inside is pretty clean today so the oil filter did its job.

It turned out that I don't have a broken ring. It looks like the scratches in the bore were caused by metal chips embedded in the piston, probably from the broken valve. There are pits in the piston between the first and second rings that match the location of the scratches. I didn't find any chips in the pits so I guess they escaped somehow. You can tell by the appearance of the top ring that it is not worn in to the cylinder wall. The second ring is. Maybe the crankcase was pressurized because the rings never fully seated.
 

Toobuilder

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Jan 19, 2010
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Mojave, Ca
Unzipped the cowl and plenum top and replaced the piccolo tube with a solid tube with the end located in the inlet near the proposed induction inlet point. With the "sensing" port localized instead of the broad average delivered by the piccolo tube, I hope to get a better handle on the true pressure the induction will see. If it does in fact deliver a higher pressure (and reduce the delta between it and the airbox), then the surgical removal of the induction chin scoop is almost guaranteed.

Flight test tomorrow after work - will post the results.
 

Pops

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Jan 1, 2013
Messages
8,800
Location
USA.
I got most of the VW disassembled today. The timing gear and the rods are still on the crank but everything else is apart. The main and cam bearings are speckled with embedded metal chips and the main journals are rough. To be expected because the original builder stuck a valve in the engine while running it in his driveway. The head of the valve broke off and the piston hammered the valve stem through the top of the head into the rocker box. He got a new piston and cylinder and different heads and bolted it back together. He told me about this and gave me pictures of the damage when I bought the plane. My mistake was that it never once entered my simple mind that somebody would blow up an engine, stick new parts on it and not at least change the oil. He kept running it with the dirty oil and I bought it and flew it a couple hours before I changed the oil. It was full of metal particles. The screen caught the big chunks but there were plenty of smaller pieces that went through the screen. It didn't have an oil filter on it when I bought it. I have since put an oil filter on it and everything inside is pretty clean today so the oil filter did its job.

It turned out that I don't have a broken ring. It looks like the scratches in the bore were caused by metal chips embedded in the piston, probably from the broken valve. There are pits in the piston between the first and second rings that match the location of the scratches. I didn't find any chips in the pits so I guess they escaped somehow. You can tell by the appearance of the top ring that it is not worn in to the cylinder wall. The second ring is. Maybe the crankcase was pressurized because the rings never fully seated.
Very good chance that the rod on that piston is bent.
 
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