What did you do on your airplane project today?

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proppastie

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Feb 19, 2012
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NJ
My instructor and I were both tired after that session. Getting recurrent is kinda tough after an 18 year absence
I have been flying often but after 2 hr. of flying I am ready for a nap.....
 

gtae07

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Dec 13, 2012
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2,107
Location
Savannah, Georgia
Fabricated the master disconnect bracket for the panel
Moved a couple components around, added some wire passthroughs
Assembled and drilled up the main landing gear

Next up, cleaning up the shop and knocking out some projects around the house :confused:
Oh, and studying for glider training...
 

bifft

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Apr 17, 2011
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301
Location
Utah
Since I started flying this plane the CHT has been a bit higher than I would prefer. I can keep it under 400F in cruise if I throttle back, but for climb and aerobatics it is usually pushing 450. Reading what other RV folks have done I heard about blocking between the top of the cowl and the "intake ramps". Tried it with duct tape and indeed takes 10-15F off.

Most who have done this did it with foam and fiberglass, but I hate-hate-HATE working with fiberglass. So I made some little aluminum ribs out of scrap and rivited them in place. Just got them done, The weight weenie in me is very please to find it only cost me 37g (0.08lb). Bet glass and epoxy would have come out heavier.
 

Victor Bravo

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Jul 30, 2014
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KWHP, Los Angeles CA, USA
I have three questions for bifft:
1) Which model RV do you have?
2) Is it fair to say you would really like to have your CHT's 30-40 degrees cooler?
3) Where exactly does the main cylinder cooling airflow exit your engine cowling?
 

TFF

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Apr 28, 2010
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14,480
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Memphis, TN
Unless it’s health related, you only have to fiberglass once and be done. Hate is short lived.
 

Toobuilder

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Jan 19, 2010
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5,117
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Mojave, Ca
There is plenty of cooling capacity in a stock RV cowl. I have smaller inlets and MUCH smaller outlets on my Rocket and it cools great, despite 50% greater heat load.

VAF has many, many threads on cooling issues and if you have not checked them out its usually a combination of little things that kills you:

Poor Delta p (leaking baffle seals, gaps in baffles, leaking inlets)
Bad ignition timing
Poor mixture
No bypass ducts on cylinders 2 and 3
 

don january

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Feb 10, 2015
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Midwest
Gee on top of building a plane and all that goes with it I get the joy of high prices and excessive shipping cost. What more to do to help save aviation this day and age. o_O
 

bifft

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Apr 17, 2011
Messages
301
Location
Utah
I have three questions for bifft:
1) Which model RV do you have?
2) Is it fair to say you would really like to have your CHT's 30-40 degrees cooler?
3) Where exactly does the main cylinder cooling airflow exit your engine cowling?
1) 8A
2) Yes, currently I limit time in climb to keep it down.
3) on the bottom. The exhaust pipes are in the way, the nose gear goes thru the same general area.

VAF has many, many threads on cooling issues and if you have not checked them out its usually a combination of little things that kills you:

Poor Delta p (leaking baffle seals, gaps in baffles, leaking inlets)
Bad ignition timing
Poor mixture
No bypass ducts on cylinders 2 and 3
I've spend lots of time reading those threads. Have checked my baffles as best I know how, haven't measured delta p. (not keen on cutting more holes in the firewall). Did my best on setting ignition timing per the marks on the flywheel, but again, don't know how good my best is. Run the mixture full rich for takeoff, running it rich at other times means my plugs clog up fast.

First I've heard of bypass ducts. Will look into that. I only have sensors on cylinders 1&4, 1 is fine, only gets up to 400 or so. 4 is the high. (Presume 3 is also, but don't have the sensor).
 

plncraze

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May 11, 2006
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2,005
You can always find a factory built aircraft which uses the same engine and use it as a reference. Sometimes folks will block the number one cylinder to bring it up while taking other measures to bring down the rear cylinders.
 

N804RV

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Jun 9, 2013
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317
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Mount Vernon, WA
RV-8: Flipped the canoe last week. Finished up aft-deck ( empennage/fuselage interface), working on cockpit rails and seatback support.

 

Toobuilder

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Jan 19, 2010
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Mojave, Ca
Did some unintentional work today... Flying home from Phoenix with just 15 minutes to go to home and suddenly the exhaust note changes significantly and I smell burning fiberglass. First thought is that I broke an exhaust stack and thats exactly what it was. Fortunately, I was with Center, at 8500 feet and directly over one of the largest ex military runways in all of SoCal. So I pulled power, called tower and landed without incident. Once parked, I called some friends and one of them headed my way to pick me up. By the time he landed I had the exhaust stack in my hand, so back to my house to patch it up with the TIG. I called another friend for the return trip and as the last bead was cooling, he pulled up to my hangar. We were airborne in minutes and headed back to grab my stranded Rocket. Pipe reinstalled and cowl going on within 15 minutes of landing - and I was home safe with the Rocket 30 minutes after that.

Another plus for the power of GA... If I had to drive that mess back and forth the airplane would still be there until next weekend. I sure had other plans for this afternoon, but all in all it only cost me 5 hours or so.
 

Rhino

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Apr 8, 2004
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873
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KTHA
RV-8: Flipped the canoe last week. Finished up aft-deck ( empennage/fuselage interface), working on cockpit rails and seatback support.
Cool. Soon you'll be able to sit in it and make airplane noises. Can't wait to do that myself.
 

Hephaestus

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Jun 25, 2014
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2,184
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YMM
I learned that 3d printing a rib mold is a pain in the ass - sanding the layer lines really sucks.

But if you vacuform a sheet of lexan over the printed mold, and keep the temps on the low side when heating the lexan sheet (185c was working for me). You can save a buttload of sanding :) Also means you don't have to reprint a mold if you don't get the release agent perfect (and the lexan doesn't really stick to epoxy resin anyway).
 

pwood66889

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Feb 10, 2007
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1,858
Location
Sopchoppy, Florida, USA
My team moved the motor from a hangar in 2J9 to project hangar at 2J0.
It was on the motor mount, and secured so good I didn't hear a peep our of it all the way down! (37.5 NM straight line)
Think I may have an engine hoist lined up for the work session Friday.
Percy in NW FL, USA
 

Rhino

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Apr 8, 2004
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873
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KTHA
Looked longingly out the window yet again at my unfinished hangar and shed a small tear being heartbroken over those beautiful, precious building moments I'm missing while I wait for my contractors to decide, "Hey, it's a nice day for working on Bob's hangar." Sadly they rarely seem to have those thoughts, and I sink deeper into my depressed malaise and regale my Labrador with stories of the adventures to come when we finally finish my plane (she renders emotional support to the process). Woe is me.

E81C5A1F-0A26-4F02-BCA3-1778311771F0.jpeg
The little room in the back will be the rec room. I'm thinking pool table, foosball, a few pinball machines, and maybe an indoor whirlpool spa.

Or maybe it'll just be the bathroom.
 
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