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AX-O's Fastback RV-4

Got a few things done this weekend. I finally got the gasket and oil pick-up blocking plate. So I installed it. I messed with the baffles some more but it was impossible to get the fit without having the engine mounted. So I mounted the engine again. After that I worked with my cowling. I got an awesome fit. Instead of using tape I made up these metal strips and drilled them onto the cowl. That allowed me to get better control of the cowl gaps. I will have to fill the #40 holes later. Also I was looking at the new intake that I will need to fab.

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Ram Air!

Axel,

When I built my -4 back in the day, the new cowl and FAB were not in production. I fabricated my own from aluminum and installed a 2" scat on top that a K&N filter could attach to. I installed a flapper door inside with a cockpit control. The result was filtered air on the ground and ram-air inflight. 15 years later it's still working for the new owner and my Rocket now has the same setup. Here's a photo of my RV4 "RFAB" several years ago before it (sniff sniff )left!

Smokey
HR2

 
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Axel,

When I built my -4 back in the day, the new cowl and FAB were not in production. I fabricated my own from aluminum and installed a 2" scat on top that a K&N filter could attach to. I installed a flapper door inside with a cockpit control. The result was filtered air on the ground and ram-air inflight. 15 years later it's still working for the new owner and my Rocket now has the same setup. Here's a photo of my RV4 "RFAB" several years ago before it (sniff sniff )left!

Smokey
HR2

Great piece of work, Smokey! Smaller than the Van's FAB, and looks less complicated too. This goes into my "Things to remember when I finally start building" file.
 
Smokey,
Thanks for the pic. Looks very simple. Was that for a carbureted set up? Was there much power loss due to the injection of hot air during taxi and take off operation? Just asking because I have 160 HP and operate in high density environments.
 
The air up there...

Ax,

Yes a Carb. The Ram air inflight always had slightly more MP than my buddies flying alongside with a FAB setup, especially at higher altitudes. Closing the flapper inflight at full throttle yielded a loss of 2" MP. In the Rocket it's closer to 3" with a Bendix Fuel Injection. The Ram air is quite impressive at SL full throttle, nearly 29" and 2800 RPM, the ASI just touching 245 MPH!
You can't get anymore air than non-restricted air even though there are arguments for turbulent airflow breakups. The only thing better might be cold air induction.

I like simple:)

Smokey
HR2
 
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Yesterday, I was able to install the side piano hinges on the cowling. BTW, look at the difference between the old intake scoop and the new one. The old one was way offset. Old scoop on the left pic, new on th right.

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Also, I contacted Rod Bower from http://www.ramairforhomebuilts.com/ regarding an air intake system. We are currently trying to install one of his systems on my plane. All I can say is I hope it will work because the system is very high quality.

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I am so getting th eurge to build again looking at this stuff!

That is going to be one sweet airplane!

Frank
 
I made the decision to mount the scoop flush with the front of the cowling. I cut off the old scoop and made some support brackets. Then I lined up the new scoop with the cowling using a 3 sockets and some string. Now I have to figure out how to rebuild the cowling.

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Axel, did you safety those two bolts for the blocking plate?

Got a few things done this weekend. I finally got the gasket and oil pick-up blocking plate. So I installed it. I messed with the baffles some more but it was impossible to get the fit without having the engine mounted. So I mounted the engine again. After that I worked with my cowling. I got an awesome fit. Instead of using tape I made up these metal strips and drilled them onto the cowl. That allowed me to get better control of the cowl gaps. I will have to fill the #40 holes later. Also I was looking at the new intake that I will need to fab.

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Last week I received a tail wheel from Dayton Murdock http://http://www.mykitlog.com/n9174l. He is the gentleman that produces the Throttle quadrant below. I removed my old Vans tail wheel and replaced it with the new one. The Vans tail wheel weighted 1238 grams (2.79 lbs) and Dayton?s weighted 720 grams (1.58 lbs). The bearings are sealed and the quality is excellent. Some pics of the wheel below.

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I don't like working of everything at once but it feels that way right now. A couple of our local EAA members built an EZ and did an awesome job. Then they fit a V8 engine in it. Anyways they told me to wait until this month to do my glassing. That would give me good resin working time and would not require the use of heat lamps. So after picking their brain, I started the process.
The first thing I did was to place tape all over my plane then paint the inside and outside of the canopy with Spray Lat plexiglass protector. Then I cut and shaped the urethane foam (makes a huge mess) and finished it with modeling clay. I was only able to work on one side yesterday. Post more later.

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Guys,
if you are tired of looking at all these pictures please let me know. I hope someone can benefit from them. The canopy is ready for fiberglass. My wife came into the garage a few minutes ago and said "wow, it is looking like an airplane".

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I laid some glass today with the help of the Spencers. They built and EZ a long time ago and have a lot of experience. We put down 4 layers of glass and used the West system. I will have to do some filling and sanding but it looks ok so far.

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I?ve been learning a lot myself, so I know I won't get tired of seeing ?em either. These steps you?re taking to do your own canopy is especially helpful for me, so hoping you'll keep us apprised.
 
Looks good Axel

Looks good Axel. I know it was more work, but I sure like the look of my RV-4 Fastback better with the fiberglass canopy skirts! I think your lines wll look a lot like mine. FYI, I received the Sam James 'best fiberglass' award ot OSH this year for my RV-4. I thought that was pretty funny! I'd say you are in the running for next year!

My plane has been flying now since end of May this year and already has 70 hours. I flew it 500 miles non-stop this last weekend and averaged 181 KTAS and it has been a joy so far, great planes, keep working!

See ya!
 
Still cutting and shaping the canopy skirt. I am posting for those people that have asked about the status. I will be riveting the fairing to the canopy frame but using Sikaflex around the canopy bubble. Still trying to figure out how the fairing will look on the right side on top of the instrument panel. I think the fairing moves inside when the canopy swings open. I can't open the canopy yet with the skirt on.

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I took her outside this weekend. It is kind of funny when people do a double take. The mailman said I am crazy :eek:

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While I wait for more fiber glass resin to show up. I started working on the cowling again. I place a piece of hard plastic inside the cowl and then used modeling clay to shape the new cowling. That is a big hole.

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Still working on glassing the cowling. I should lay the last strips today. Here is the progress so far. A lot of learning going on with this fiber glass stuff.

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Dude, I've just got to say, you're doing an amazing job. This thread has become the thing that makes me want to get out and build my -4 some more. If only life would get out of the way and let me finish!

I love that this has pretty much become a 'build' thread, like some of the car forums I frequent...

I'll give you a call later. I got to get this **** C150 done and out of my hanger.
 
Thumbs up Axel!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

Looking great!!! I know what your going through. Take your time and do it right the first time. I'm good friends with JJ (Jetj01) if you know who he is. This yr (08) he received the Sam James fiberglass award at Oshkosh. I received the same award in 2007 at Oshkosh with my RV-6 from Sam James. YOUR next on the Award list! Heres a link to some of the mods I've done on my RV if you haven't seen them or are interested in a few ideas. I haven't been on VAF for quite some time so you might not of seen some of the mods I've done on my -6. Heres a couple of links you can check out if your interested, KEEP up the excellent work!!!!!!!!!!!!
http://www.vansairforce.com/community/showthread.php?t=12633&highlight=Cowling+mods

http://www.vansairforce.com/community/showthread.php?t=20548&highlight=Sam+james+fiberglass+award
 
Dude, I've just got to say, you're doing an amazing job. This thread has become the thing that makes me want to get out and build my -4 some more.

Steve,
glad this can give you motivation. It is one of the reasons I post progress often.

Looking great!!! I know what your going through. Take your time and do it right the first time. I'm good friends with JJ (Jetj01) if you know who he is. This yr (08) he received the Sam James fiberglass award at Oshkosh. I received the same award in 2007 at Oshkosh with my RV-6 from Sam James. YOUR next on the Award list! Heres a link to some of the mods I've done. KEEP up the excellent work!!!!!!!!!!!!

http://www.vansairforce.com/community/showthread.php?t=12633&highlight=Cowling+mods

http://www.vansairforce.com/community/showthread.php?t=20548&highlight=Sam+james+fiberglass+award

I have seen those links and realy appreciate the hard work. I spoke with JJ at OSH this year. His airplane got a lot of attention. I don't know about any awards, I am just building my plane so I can be proud of my work and perhaps other builders can appreciate the work. Thank you for the kind words.
 
Man I now know why I did not build a Lancair. There is glass dust everywhere. This is the cowling with 2 coats of micro. I think that stuff is going to my head and affecting my mind. I needed a shirt and a hat and this is what I found.

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Get Back on the Weights!

Axel:
Biceps look OK, but the Pecs are pretty sorry. Hit the bench- Heavy weights and low reps. Protein shakes will probably help too.
Terry
 
Axel:
Biceps look OK, but the Pecs are pretty sorry. Hit the bench- Heavy weights and low reps. Protein shakes will probably help too.
Terry

You noticed too :eek: I stoped going to the gym to finish this plane. Now I get up at 0500 to work on the plane vice going to the gym. Guess I better take your advice.
 
Axel,

Looks like you've got too much time on your hands! The only reason I didn't ask you up to Tehachapi to help me close a tank last Saturday was that I thought you'd be busy on your fastback. I see now I was wrong...:D
 
Axel,

Looks like you've got too much time on your hands! The only reason I didn't ask you up to Tehachapi to help me close a tank last Saturday was that I thought you'd be busy on your fastback. I see now I was wrong...:D

You would have to be my BFF. That is the only way I would touch another fuel tank:D

Cowlgut instead of beergut... I like it!
Smitty, I like it and my wife likes it as well. I think you coined a new term.
 
muffler tape?

Axel, I saw in some of your early photos there was some sort of fabric tape on the mufflers. I've seen this on some racing motorcycles too. What exactly does this help with? Help keeping the heat going out the exhaust? Maybe dampens some of the vibration?

Chris.
 
It is a fiberglass insulating wrap. Designed to keep the heat in the pipe, and the radiant down. It works good, like heat shields do. The downside is the increased temp the pipes opperate at can effect the longevity of the exhaust system. For some applications, its an acceptable tradeoff.

Axel, I saw in some of your early photos there was some sort of fabric tape on the mufflers. I've seen this on some racing motorcycles too. What exactly does this help with? Help keeping the heat going out the exhaust? Maybe dampens some of the vibration?

Chris.
 
Axel, I saw in some of your early photos there was some sort of fabric tape on the mufflers. I've seen this on some racing motorcycles too. What exactly does this help with? Help keeping the heat going out the exhaust? Maybe dampens some of the vibration?

Chris.

Loopfuzz,
it was header wrap from spruce http://www.aircraftspruce.com/catalog/eppages/genIIcopperwrap.php

I wanted to keep the heat in the pipes. That way there would be no chances of burning the cowling. Turns out that doing this is bad for the pipes. The wrap keeps the heat inside and diminishes the life of the pipe. It also makes the temperatures in the engine much warmer. The wrap does not allow the pipes to air cool. I spoke with Larry Vetterman and he told me to remove the wrap. I sold those pipes and will be buying new ones soon.

Look at this thread and read post number 18.http://www.vansairforce.com/community/showthread.php?t=34814&page=2
 
There is glass dust every where :eek: Still moving along. I have the final scoop configuration for now. All the imperfections will be easier to spot after I spray some primer/filler on the cowl. I was also able to finish the piano hinges.

The canopy skirts are coming along as well. I had to cut the back of the skirt to get a better fit (I think due to the temperature change and the tape under the fiber glass). It was 95% perfect. I wanted 99% I glassed over the cut with 3 layers of fiber glass/resin and some flux. Can't tell the difference.

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Nice Work!

Axel - great glass work there! Well done.

Im getting ready to start my canopy and skirt install for my -8. Curious how you were able to create such a straight line at the skirt/canopy interface? Did you use fiberglass tape with a woven edge? If not, how were you able to sand the edge down without damaging the canopy in the process?

Thanks!

Spank
 
Axel - great glass work there! Well done.
Curious how you were able to create such a straight line at the skirt/canopy interface? Did you use fiberglass tape with a woven edge? If not, how were you able to sand the edge down without damaging the canopy in the process?
Spank


I used 4 layers of BIDIRECTIONAL 8.8 oz Rutan fiberglass (Spruce P/N RA7725).

Here are the steps I took.
- Marked where I wanted my canopy skirt
- Filled the canopy gap with foam and shaped it
- Smooth everything out by adding modeling clay
- Applied tape to the canopy and airframe
- Laid the glass (aft, sides, front) and overlapped them
- Let it cure for a week
- Grabbed a corner of the glass and started pulling the skirt away from the canopy/airframe
- Once it came off, the blue marker lines were stuck to the fiberglass
- Used those metal cutting pliers we have with our building kits to cut the glass very close to the blue line
- Cut a piece of 18 inch 2X4 and wrapped it with 60 grid sanding paper
- Sanded the edges until I was happy
- Beveled the edges with fine sand paper
- Placed the shaped skirt on the airframe
- Drilled 6 holes on the canopy and all the holes required on the canopy frame
- Sikaflexed the skirt to the canopy
- Riveted the skirt to the canopy frame

The skirt is not finish yet because it got cold and my shop is not heated. Once temps get up again, I will be applying micro on the skirt to make it as flawless as possible. I hope that helps.

BTW, thanks for the kind words.
 
The skirt is not finish yet because it got cold and my shop is not heated. Once temps get up again, I will be applying micro on the skirt to make it as flawless as possible. I hope that helps.

On my rocket I made all of the skirts out of .025 using an english wheel and a shrinker/stretcher. I did this in warm temps and I can't get a fingernail underneath the rear skirt and the turtledeck. But when the shop is cold the rear skirt will come off the turtledeck by 1/16" almost all the way around. Its due to the canopy expanding when its warm and retracting along its length when cold. Its not a problem at all but if I had to do it over I would have fit everything in cool temperatures.
 
More updates.

I received a bigger air filter canister from Rod Bower. The new size meant I had to turn the fuel servo 180 degrees from the original set up in order to have the required clearance. I also had to redo my control cable brackets and routing. The installation is almost completed. I may send my fuel servo back and have one of the fuel fittings changed to get a little more room.

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I have been working on the baffles and plenum as well. This ranks up there with building the fuel tanks. When does a part stop belonging to a company and becomes yours. I have cut the plenum to pieces just to get it to line up. I think I should just have made my own plenum vice spending the money on one from Sam James.

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Its not a problem at all but if I had to do it over I would have fit everything in cool temperatures.

The glass resin has to be applied at specific temperature. That is the reason I am going to wait. I did notice the fit changed with the temps. Thanks for the heads up.
 
Some more progress with the baffles and plenum. The new glass is curing. I should be able to peel the plenum off tonight. I applied mold wax to the engine and baffles. I hope it does not give me too much problems when I take it off.

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Well guys, I think the baffle/plenum fabrication is over. I will clean it up and paint it later. Some pics below. My Pmags showed up today. I will be looking at the installation tomorrow. I have to figure out how to run the wires and all that. Hope the car plugs, 18/14 mm adapter and ignition wires fit under the plenum. Does any one now what is the shortest car plug I can run on the top?

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Looks Very Good

Looks very good Axel, nice job. As a final seal, you might consider spraying Pol-Ease on the baffles and the front of the engine, and putting a bead of high-temp RTV on the plenum where it interfaces with the baffling and engine. Bolt it down and let it sit for a few days before you pull it off. If you have any thick spots you might want to let it cure in situ for a week.

You probably already know this, but don't forget to put air dams on the front of cylinders #1 & #2.

Lookin' good!

Hans
 
Looks very good Axel, nice job.

You probably already know this, but don't forget to put air dams on the front of cylinders #1 & #2.

Lookin' good!

Hans

Thanks for the kind words Sir.

I made a removable dam for the number 1. Don't have anything for the number 2 but can very easily make one (if needed). Making it removable will give me some flexibility during flight test. I will post some pics of the number 1 dam later. Don't have pics right now.
 
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