hydroguy2

hydroguy2

Well Known Member
I've been asked to help finish a RV-4 project. The original builder has passed and almost no documentation on the current work. So looking for info.

I've read some of the posts concerning Long vs Short gear so understand the issues there....BUT how do I tell if a project has the short gear or long gear? Also any good pictures of firewall/ longeron weldments or reinforcement to see what we have.

the cowl has been fit, but no prop or spinner. There is a 6" prop extension bolted to the motor, but looks kinda long to me. what's normal?

I'll have more questions soon as we dig deeper.
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I think the wrong engine is installed, This 290hp IO540 was in the corner.
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No, that 540 won't work. Also, It's virtually impossible to set up the cowl with out the motor and spinner already in place as the cowl is set to line up with the spinner.
You need a builders manual, ($50 from vans) it will give you the length of both the gear and and prop spacer.
 
I was joking about the engine....for this project.;)

The only builder manual I've seen so far is pretty old and didn't dig deep into yet. I was only there far a hour or so, we're just getting started. Also the engine is mounted and I think a prop/spinner was on it at one time. I think the kit number is 126 or something like that. Metal work looks good as does the wiring. Lots of old school stuff and recycled instruments, etc. Engine is a Lycon overhauled 0-320 E2D, still pickled.
 
The builder's manual for the early RVs is nowhere near as clear and helpful as the new ones like for your -7 but with your building experience you will be able to fill in the blanks much more easily.

You may be able to cross reference with your -7 manual for help where the -4's manual is lacking since there are many more similarities than differences.

Good Luck...let us know how it goes.

Glenn Wilkinson
 
Brian,

Take a look around here:

G-IKON

This is Stephen Sampsons website and is one of the best RV-4 sites for info. you may have to search around this site a bit but it is well worth it. Also, take a look at maybe the firewall area as mentioned here in a pm to me from smokeyray.

Originally Posted by smokyray
Hi Tony,

Yes, I beefed up the firewall area at the forward longeron attach points. They are identical to the Harmon Rocket attach points and they should be incorporated into post 1995 RV4 kits as the "heavy weldments". I went beyond this and used .040 doublers on the inside of the forward fuselage where the engine mount holes come through. All this adds strength and helps reduce the bending moment loads on the lower engine mount. I may have photos, I will look around.

I sold my 4 and my HR2 and am now flying a hybrid,
RV6 fuselage with Rocket wings and RV4 tail. I call it the "RVX" Cheers!

Smokey


Quote:
Originally Posted by islandmonkey
Hi Rob,

Talking to Steve Sampson, he mention that you may have beefed up the front end of your 4 with thicker skins in the firewall area. Steve says he did not do this to IKON but only added the thicker skins on the emp. Can you confirm please.

Thanks in advance.

Tony
Click to expand...
 
The owner found the new builder manual. Also found info that the engine had higher compression pistons installed by Lycon, so 160hp.

We're looking for recommendations on seats, seatbelts, prop,..........this is going to be fun!
 
Before standardizing on the shorter cowling, Van sent cowlings for a 4" extension for F/P and a shorter cowling for C/S prop.
After standardizing on the shorter cowling, the F/P uses a 2.5" extension.
 
Prop extension

Believe the standard now is 2 1/4 . What dia is the spinner back plate? probably has short gear legs if they are not pre drilled. The builder manual will explain the fixed pitch vs constant speed cowl and which extension is required. 6 inch extension wasnt an option I dont think unless he had an odd prop. I think the bigger firewall weldments are .050 vs .040. If they are the thinner ones I would replace them.

Looks like fun

Cm
 
The old cowls were set up for a 12" dia spinner - so be careful when ordering a new one. A 4" extension was standard to start with. I have a set of short gear legs in the garage, they are 40.5" from the top to the centre of the axle. Hooker & Crow both do seat belt sets.

Peter
 
Montana RV-4

Mike has been working most everyday with the goal of flying this summer. So last night I went over and helped him put the wings on. these long laminated spars are little tougher than my -7. We generated a page of parts/supplies needed and a ToDo list for both of us. It was a real good work session.
wingsRV4.jpg

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Moderator Q...any chance someone can change the original title from "RV-4 project questions" to read " Montana RV-4 project". as I will be giving periodic updates. thanks BC
 
Weekly update:

Mike drilled out the pop riveted wing tips and started installing nutplates. good thing too, as he found some screws holding the nav lights on with nuts vs nutplates....and no way to service them if they failed. Mike also has entered the world of Aircraft Spruce on speed dial. Mike is working on interior wiring runs to the tail area and figuring out possible changes to the panel. he is going to eliminate the belly beacon and go with a strobe set up.

I made the forward wing attach brackets, then went up there last night. We fitted the aileron push/pull tubes and riveted the ends on. When we tried to fit the flaps, we found they hit the fuse and need notches cut. Also need materials to fab the flap handle pieces and connecting rods. Wings should be done in a week or 2.

Baby steps but we're moving forward. Anyone got a Catto prop 160hp RV-4) they want to get rid of?
 
Think about electric flaps

Brian,

It sounds like you are planning on putting the old manual flap system in. it is simple and light, but is kind of in the passengers way and takes up valuable room. I would recommend you at least consider electric flap retrofit. My two cents.
 
just saw this post, after Mike told me about it. He is thinking of going with the electric flaps(now is the time) We'll be checking into what it takes. so...Thanks Brent.

Do you have any "should do or must do" mods you recommend for the RV-4's. I only see the back end of yours occasionally. :D
 
Crow Harnesses

I am fitting Crow Harness and I am very happy with them. One of the few purchases I have made for the 'plane that wasn't insanely expensive.

http://rv-4builder.blogspot.com/2011/05/harnesses.html

I am also looking at the electric flap option and am using steam guages and minimal electrics.

Would be curious if the Kit number was 120 (or there abouts). Mine is 2265 and I perchased it in the 80's. Your plane would be a piece of history before it ever flies (like mine).

It looks like a tidy bit of work. So sad the builder put all that effort in and never got to see it finished in this world.

Good Luck !
 
hydroguy2 said:
...Do you have any "should do or must do" mods you recommend for the RV-4's... :D
Click to expand...
Brian,

There is a foot well mod for the back seater. I'm not sure if this is a Van's kit or someone else's idea. The back seat of the -4 is a tight place and this gives them just a little bit more room.

Maybe one of the -4 builders can elaborate.
 
Rear footwells.

Yep...what Bill R. said.

We added the deeper passenger footwells to my buddy's -4. They're easy to make if you don't have them. It's basically a recess in the floor that allows rhe passenger's feet to be down in a lower space...much more comfortable too.

Best.
 
-4 stuff

Brian,
I put the rear foot wells in mine (simple home brew )copied from pics I saw. No real science ,just make sure they clear the aieleron pushrods. My GIB who is with me nearly all the time is almost 6' tall and she fits great..I at 6'1" have been in the back of a "non foot well" -4 and the knees are in the roll bar attach point. I also installed the electric flaps,elevator and aieleron trim, all operated from the stick grip (MAC). I LOVE the setup, as I never have to take my hands from the stick and throttle, as well as it frees up GIBs foot area. I put a rear seat air vent,via NACA duct in right wing lower surface with a SCAT to a nozzle in a rear stick console. This also provides a boot and cover for the rear stick mechanism...imagine the backseater dropping a camera or phone in the monkey motion and things could get real exciting !For the front, I have the NACA ducts on left and right side below the cowl cheeks..gets hot here in the south, and the -4 will heat up quick in the sun. A taxi position latch for the canopy (open about 1"-2") is also a warm weather need, and I havent done that yet,but I will before June !
 
fixnflyguy said:
Brian,
I put the rear foot wells in mine (simple home brew )copied from pics I saw. No real science ,just make sure they clear the aieleron pushrods. My GIB who is with me nearly all the time is almost 6' tall and she fits great..I at 6'1" have been in the back of a "non foot well" -4 and the knees are in the roll bar attach point. I also installed the electric flaps,elevator and aieleron trim, all operated from the stick grip (MAC). I LOVE the setup, as I never have to take my hands from the stick and throttle, as well as it frees up GIBs foot area. I put a rear seat air vent,via NACA duct in right wing lower surface with a SCAT to a nozzle in a rear stick console. This also provides a boot and cover for the rear stick mechanism...imagine the backseater dropping a camera or phone in the monkey motion and things could get real exciting !For the front, I have the NACA ducts on left and right side below the cowl cheeks..gets hot here in the south, and the -4 will heat up quick in the sun. A taxi position latch for the canopy (open about 1"-2") is also a warm weather need, and I havent done that yet,but I will before June !
Click to expand...

Brian,

I agree with all of this.

I do not have a NACA vent on the wing bottom for the GIB but I wish I did.

NACA ducts on the sides just behind the firewall below the cheeks are a must.

Footwells likewise. I started without and then installed them. Leave room for the aileron pushrod. This makes the back much more comfortable.

You can get a flap control board from Vans that acts like a relay so you can put a small switch on the stick for the flaps. It works great. Advanced Flight Systems makes it.

I also think that a slightly open position on the canopy that truly locks is an absolute must have. I did not have this at first and I was holding the canopy open with my hand one day and a gust of wind yanked it open, it broke the lanyard, and caused a couple of weeks of repair and downtime.

I have also tested my slightly open canopy in flight, I do not recommend this, but now I know it works. Don't ask. Maybe I should fly over and let you guys take a look, or you could fly over here and try my SARL course out.
 
N999BT said:
.......Maybe I should fly over and let you guys take a look, or you could fly over here and try my SARL course out.
Click to expand...

Now that sounds like an excellent idea. Normally my motto is: will fly for food...but fly for racing is good enough for me.;)

Thanks for the tips you guys. He already has foot wells, and is ordering the electric flap conversion. I have seen the backseat vent mods, Any pictures?

We're trying to finish up the wings next week, his painter friend has an opening.
 
History and Update on project

Okay, now that Brian has been mentoring me on this project for a couple months, and I've been lurking around this forum for longer than that, I actually think I have enough knowledge to start asking some of my own questions and give some of my own project updates.

I'll give a little background for those who might be interested:

A best friend of mine, Rick Borgmann, got interested in flying in the early 90's. He got his PPL, went to Cheyenne AeroTech and got his A&P, and then got a job with Butler Aircraft in Bend Oregon as a mechanic, and eventually flew in the right seat of a DC-6 retardant bomber with our mutual friend, Del Hunt. Around the same time, Rick got real excited about RV's and purchased a partially started -4 from someone(whom I don't know). The number on the plans is 128, so it's kind of old. He worked on it for a number of years off and on. He basically got most of the surfaces done. Had the engine hung, partially baffled, no seals. Had a fair amount of the wiring done with mostly old steam gauges.

Brian and I have worked together at a hydroelectric plant for the past 20 years or so. Brian got interested in building an RV about 6 or 7 years ago. I introduced him to Rick and partially based on his conversations with Rick, Brian started building a -7. A year or two later, Rick died in a tragic manner at the hands of his own father in a murder/suicide. I knew that Rick loved the plane and wanted to fly it and I felt sentimental about it. So I bought it out of his estate with a personal pledge to myself that I would finish it and fly it in his memory. Although I consider myself a skilled hydro turbine mechanic, I've never known much about working on or fabricating airplanes. So the plane has been sitting in my shop for the last 5 years with me wondering what I got myself into. I've never been able to find any builders log. I've got the original plans which look sort of like Egyptian parchment. So I contacted Van's, sent them a copy of the legal document that conveyed the project to me, and they sent me a copy of the original plans along with a builders manual. Still didn't do me much good.

Fortunately, Brian learned quite a bit while he was building his -7. I visited with him at work a lot and followed his progress. And I'll be darned if he didn't finish it!!! I followed his progress through his first flight and testing phases and it was all pretty fun and exciting.

Anyway, I still didn't make any headway on this project. Just didn't even know where to start. But evidently, once an airplane builder-always an airplane builder. Because Brian started bugging me about finishing the -4. I think he just needed a "fix". So last November, I started by REALLY cleaning my shop out and organizing tools. Then in December, Brian and I scheduled a date to "look it over". Now it's "Katie bar the doors" and the rate that my brain is trying to absorb all the knowledge that is coming at me through this forum and directly from Brian?.well ?..it's sort of like trying to drink from a fire hose!!! At first I felt like an absolute idiot, but with patience, Brian gave me Riveting 101 and I started by drilling the rivets out of the wingtips and replacing them with nutplates. Slowly but surely, I'm inspecting every bit of the work that has been done and planning all the work that is left to be done. I really didn't realize that there was SO MUCH left to be done. But now I know enough to know THAT, which is good.

So here's the status as of today:
Brian and I started by focusing on the wings. My friend, Travis Elbert, who paints airplanes, has an open week in his shop and he owes me a favor so we wanted to take advantage of that.

We put the wings on the plane. Learned that Rick had already drilled the hole in the rear spare attach. Double checked everything with strings and plumb bobs. Not bad. Put the level and the block of wood on the wings and found that the wing had more incidence than called for. As I recall, with the siderails level, there was about a quarter inch of air between the block of wood and the level. So we worried about this for awhile and searched the forum and made some calls. Decided that the solution was to prop the tail up a little more(siderails no longer level) so the wing level sat on the block like it was supposed to. Then, we checked the HS like the plans say to. It was flying downward about 3/16"(if I recall correctly). We figure we will shim the leading edge of the HS so it is correct in relation to the wing. Then the fuselage will be slightly off from design optimum, but we think we'll be okay. If anyone wants to weigh in on this issue, we'd listen.

We cut the aileron pushrods to length and riveted the ends on.

We cut the weird holes for the flap actuating rods. I looked at the result in disbelief, but Brian reassured me that all RV's look like this. Besides, it's covered over when the flaps are up. BTW, because of the advice in this thread, I'm getting rid of the flap handle and installing electric.

We hauled the wings to the paint shop. Then, in the meantime, I decided to rip the steam gauges out and upgrade the panel. That means I needed to put in a pitot mast for the AOA probe. So I have a panel upgrade going already. :) The pitot mast is SafeAir1. It was fantastically easy to retrofit to the wing through the existing inspection cover. The instructions were great. Since I couldn't find the instructions on the SafeAir1 website or the Avery website, I think I'll scan mine in and post them to the forum under the proper thread when I figure out how to do that next. They would be helpful to anyone considering the retrofit.

Now that the wings are gone, I'm on the fuselage full time and wishing I didn't have to go to work on Monday. I've ripped out the old panel, and basically all the wiring. I've got a fake seat installed in the cockpit and spend a lot of time sitting in it looking at everything and making airplane noises. Throughout the course of today, I came up with about a bazillion questions to ask Brian next time I get him over here.

I'm going to seriously look at the NACA duct under the wing for ventilation, and the taxi position latch for the canopy. So thank you guys for those tips! I'm pretty sure that I have the short landing gear so I will be doing more research to decide if I want to do anything about it. Probably not. Opinions welcome.

So now, for those of you who are still with me. I better ask at least one question:

We've decided to eliminate the heavy Concorde battery and cable from the luggage compartment in favor of a PC680 up front. I'm in love with the idea of locating it on the front of the firewall and have seen the discussion about heat, etc. I haven't seen anything to make me want to put it on the aft side of the firewall though. If anyone has heard anything definitive saying it shouldn't be inside the cowl, please let me know.

I think Brian was right when he told me the toughest and most time consuming thing about building airplanes is making decisions!!

Thanks for listening, and all the help so far. Hope I don't get kicked out of the forum for making such a lengthy intro!! The following posts will be shorter. I feel certain I'm going to get this older bird flying. :rolleyes:

Mike
 
Welcome to VAF, Mike

Y'know, it's a lot like building a house....one brick at a time.

You seem to have a good grip on focussing on one structure at a time and that's the way to go.

Best,
 
Mike,
Sounds like you have good help and are on the right track. I think you will find it difficult to put your battery on the firewall given the room available. Not imposible but difficult. The standard configuration is to put it in the forward tunel between your legs. I would suggest just putting it as far forward as you can. Depending on Eng prop combo IE an 0320 with a fixed pitch prop the -4s are a little on the tail heavy side with passenger. I would very much consider what the other guys are saying about the footwells, very nice for the passenger and pilot. Enjoy the build!
Ryan
 
hey Mike, your first post must not be too long, no one deleted your account. :D

Keep drinking from that firehose, you are figuring it out pretty fast.
 
Welcome to VAF!!!!

Mike, welcome aboard the good ship VAF:D

Battery location is not something that is cast in stone, it is a tool to accomplish one of many compromises that happen when designing a plane.

The battery that was in common use when the 4 was designed is not the common battery for today's homebuilt, as has been stated.

You need to look at the trade offs that will be effected by a change in battery and location-------maintenance access, weight/balance, wiring issues, ETC.

What engine and prop you plan to use are a definite factor in battery placement.
 
Battery

Mike,
I put my battery in the tunnel as per plans, and also put my radio stack in a center consol . This makes battery access a pain in the *&^ as the radios have to come out, and the front skin has to be unscrewed,ect. Just finished my anual condition inspection, and I did alot of thinking/measuring while in there...I have an "all electric" plane, dual electric fuel pumps,flaps,trim ect., so my battery is pretty important. I am planning on installing a second battery on the front right side of the firewall, and it looks like it will easily fit with a battery box attached to the r/h side of the engine mount , so its actually in the cowl cheek. I will put an air blast type tube into it, venting out the bottom. I had also considered while building, a removable structural belly panel that could be unscrewed and drop the battery out the bottom, however I didnt do that. I recommend you look at the forward location, and use the tunnel for storage,ect.
 
Firewall Battery

Mike,
There is room for a PC680 battery on the firewall. The "tail heaviness" of a light nose -4 (O-320/fixed pitch) can be modulated with crush plates or a balance ring on the flywheel, if required. Van sells a mounting kit that can be adapted to the -4.

Cheers,

Vac
 
Battery

My configuration did not allow me to put the battery on the firewall. I ended up putting the battery in the right cheek of my -4 as a retrofit. I built a box out of aluminum, and attached it to the engine mount with Adel clamps. It's tight, but it works.

I originally had the battery in the tunnel and a center radio stack. One big advantate of getting the battery out of the tunnel is that now I use that for forward baggage on a trip. It allows me to take as much as about 20 lb more stuff than I otherwise could when m wife travels with me. Bottom lin, I am glad I changed it, and I like how it turned out. Usually I have to build things three times before I am happy, but this time it was only two.
 
We got the wings ready for paint last week. We have turned our attention to the fuselage, but Mike has been helping the painter lately. Tonight I got 2 pic on my cell phone. So the colors are typical of many cell phone and aren't correct. The actual colors are Cream, almost Navy Blue and a brighter Red based on a Cherokee his Dad had long ago.

Mike pretty excited and this will give him a real "Get R done" boost.
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