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  #11  
Old 04-27-2016, 09:43 AM
rightrudder rightrudder is offline
 
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Location: Laguna Hills, CA
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Quote:
Originally Posted by MarkW View Post
Good job Chris. Seems like you are doing a good job of working through the small things.
I know landing wasn't the major point of the post but one thing you probably already know is that the float is very exaggerated by idle speed. Once you are comfortable with the cylinders being broke in make sure to keep the idle low. Even so low it almost stalls while on the ground. While flying and with the prop windmilling it will be a much higher idle speed. I have seen high idle RV-9's that can hardly land in 3000'
^Agreed. I bumped my idle up by maybe a quarter turn (rpm went from 650 or so to 700) trying for a little more smoothness. After the first landing, I put it back. Even with the windmilling on final it feels a little lumpy, but still responds instantly to throttle input.
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  #12  
Old 04-27-2016, 10:13 AM
Rupester Rupester is offline
 
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Good post, Chris! I found myself smiling the further I read thru your findings .... My reactions were - and in some cases, still are - identical. I thoroughly identify with the Nine's desire to climb and the importance of sight picture over the cowl. Before my Nine I had >350hrs in C172s, which has a flat top cowl. For at least a year of flying the Nine, I regularly trimmed for cruise only to find myself climbing at 400-500 rpm just a few minutes later. It took a long time to acclimate to my James cowl and its downward sloping snout .... Not to mention the climb rate of an RV.
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  #13  
Old 04-27-2016, 11:06 AM
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airguy airguy is offline
 
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Location: Garden City, Tx
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Originally Posted by Rupester View Post
Good post, Chris! I found myself smiling the further I read thru your findings .... My reactions were - and in some cases, still are - identical. I thoroughly identify with the Nine's desire to climb and the importance of sight picture over the cowl. Before my Nine I had >350hrs in C172s, which has a flat top cowl. For at least a year of flying the Nine, I regularly trimmed for cruise only to find myself climbing at 400-500 rpm just a few minutes later. It took a long time to acclimate to my James cowl and its downward sloping snout .... Not to mention the climb rate of an RV.
Same here, almost exactly, just a little more time in the 172. I still get surprised by the desire to climb aggressively even in a high bank angle, and the sight picture over the cowl took some getting used to.
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Built an off-plan RV9A with too much fuel and too much HP. Should drop dead any minute now.
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  #14  
Old 04-27-2016, 11:29 AM
YellowJacket RV9 YellowJacket RV9 is offline
 
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Location: Clearwater, FL KCLW
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Thanks all. My idle is around 630-650 right now. It doesn't float much when I am on speed. When I get it right, I can stop well before my first turnoff. At some point I will experiment with even lower idle though - especially if I move to a pmag at some point.

I got a tip about my oil leak also possibly coming from my breather tube, so I may make an extension for it and see what happens to the leak. Thanks for all the suggestions!

Chris
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RV-9A - Done(ish) 4/5/16! Flying 4/7/16
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  #15  
Old 06-05-2016, 09:33 AM
YellowJacket RV9 YellowJacket RV9 is offline
 
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34 hours down now, and still grinning, even more so after blowing by a 172 yesterday like he was standing still. And I was climbing.

I have been working on my timing with respect to getting slowed down, and experimenting with different ways to fly the pattern. Also did a no-flap landing yesterday. Practicing more stalls which are non-eventful but I still need more work flying right above stall speed.

I have my main gear fairings and intersection fairings attached, and plan to do the nose gear leg fairing this week. Definitely a bit faster now.

I broke down and bought a used Lightspeed Zulu. Never going back.

I have also semi-permanently installed the Stratux box which is now hardwired to my GRT Sport. I love being able to pull up METARs, especially since our ASOS transmitter at ZPH has been down for weeks. I also bought an AP510 APRS transmitter that I finally got setup last night and will test next time I fly. Yes, I have a license (AE4KN).

I had slightly high CHT's on #3, which had been reduced by triple-checking all my baffle seals, as well as adding the gear fairings, however #3 was still just barely below 400* at 75% cruise (although it is quite hot out). A few days ago I finally bit the bullet and fabricated a channel into the rear of the #3 baffle that directs some air under the cylinder. Noticed immediate improvement now with #3 well under 390* even with higher OATs yesterday. I still think I can do better though because #1 is around 350-360*. I think adding to the air dam or at least some speed tape on #1 can help even out the temps. The only challenge is that #1 tends to get hotter faster on climb out, so I want to keep it cool enough in climb as well.


Other squawks: My old Dynon D10 backup EFIS has the leans, and indicates a slight left bank while straight and level. If it's a hardware issue my only option is to upgrade to a D10A I guess. But since I'm not flying IMC I'm not immediately concerned with a backup EFIS. Besides, the airspeed and altitude on it work fine.

Baffle cracks: Sure enough, the baffle is cracking along the outside left rear corner at the oil cooler mount. Tomorrow I am going to fabricate a doubler angle that will be well secured, with the goal of lasting until I order some new parts and make a beefier setup. Should've listened to those before me...

Everything else is going well, and I am experimenting with leaning technique, and will start a separate post with some of those questions.

Chris
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  #16  
Old 06-05-2016, 08:20 PM
rightrudder rightrudder is offline
 
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Wow, speedy progress through Phase 1! Poor Cessna 172 didn't see it coming.

Sorry to hear about your baffle crack. Did it occur at the top of the intersection? When you redo the baffle, consider fitting some sort of brace to reduce the flexing. Lots of variations out there, but I bolted a piece of flat stock directly from the baffle (with a D-shaped gusset) to the cylinder head fins of #4. It's remarkable how it stiffens things up.

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Donation made for 2021
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  #17  
Old 06-05-2016, 08:42 PM
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Steve Melton Steve Melton is online now
 
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this simple and compact alum oil cooler brace has been successful for 450 hr. no signs of distress. I think the key is attaching to the oil cooler bolt. this is on the old style baffle kit. no other added pieces to baffle kit other than the brace.

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Last edited by Steve Melton : 06-05-2016 at 08:52 PM.
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  #18  
Old 06-05-2016, 08:46 PM
YellowJacket RV9 YellowJacket RV9 is offline
 
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Quote:
Originally Posted by rightrudder View Post
Wow, speedy progress through Phase 1! Poor Cessna 172 didn't see it coming.

Sorry to hear about your baffle crack. Did it occur at the top of the intersection? When you redo the baffle, consider fitting some sort of brace to reduce the flexing. Lots of variations out there, but I bolted a piece of flat stock directly from the baffle (with a D-shaped gusset) to the cylinder head fins of #4. It's remarkable how it stiffens things up.
Actually, my crack is on the outside of the baffle at the rear corner. I have seen others with cracks here as well, although I do plan to brace the entire area and hopefully avoid any more.



Chris
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  #19  
Old 06-05-2016, 10:03 PM
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bruceh bruceh is offline
 
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The reason that the crack is where it is, is because that is where the baffle is flexing with the weight and vibration of the oil cooler. If you brace the inner side of the oil cooler to something, then that vertex of the baffles won't flex and crack.

I added this brace between the oil cooler and cylinder head and it makes it extremely stiff. No cracks (yet).



Stainless steel tubing, flatten the ends, drill a hole at each end and then use a longer bolt on the rocker cover. The hard part is getting the angles of the bends on the tubing correct.

I also reinforced the baffle with some angle.

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  #20  
Old 06-05-2016, 10:09 PM
YellowJacket RV9 YellowJacket RV9 is offline
 
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Quote:
Originally Posted by bruceh View Post
The reason that the crack is where it is, is because that is where the baffle is flexing with the weight and vibration of the oil cooler. If you brace the inner side of the oil cooler to something, then that vertex of the baffles won't flex and crack.

I added this brace between the oil cooler and cylinder head and it makes it extremely stiff. No cracks (yet).
Makes sense. I will incorporate this idea for sure; thanks!

Chris
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