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Shawn's -4 re-build

ShawnR

Well Known Member
Friend
Hi all

In a couple of other threads, I started asking questions about RV-4's before I bought one, then found one that was complete and flying, with a 180 hp in it, which was appealing. It was not so nice that I would be afraid to take things apart and start making changes. I need to learn about how these are built, and update it to what I might want (not sure what that is yet, but that will be part of the journey).

Happy to say that I received my new ride last week. I will need to get checked out for insurance and it needs those rear rudder pedals I mentioned in other threads. Since our flying season is almost over, I won't be airborne in it again this year. The seller did take me up when he first brought it here for me to see. As much as I have been in other RV's, I think I might have had the RV grin for the first time when I realized I might actually own one one day.

This thread was the start of my questions, in case some of you feel like we discussed this before, but now I think I will put updates to the rebuild process into this thread here to avoid a bunch of random threads going with my many questions that I anticipate.

I will be looking forward to input from those of you with experience in owning, building and or flying them. The plane first flew in 1984 so if I understand correctly, there will be a few updates that I can do. As I sat in it, looking around for ideas and changes that I might make, I felt overwhelmed with the idea of starting one from scratch! My hat is off to those of you with the focus and determination to do so. I view my plane as an ultimate fast build. It has flown with 500 hours, so tested, yet will need some updates and parts possibly redone to make it nice(r). I am hoping to have it airborne in the spring. Up here in Northern Canada, there is not a lot of flying off of grass strips anyways in the winter, so it will be a good time to get er done.

Attached is a few photos to give you an idea of what I am working with. I have always liked fixing up old stuff so will see what I can do with a homebuilt aircraft. I am not expecting to make it into a show plane, but do want something I am proud of. I think there is a lot of (enjoyable) work ahead of me. ;)

Cheers all,

Shawn
 

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Congrats on your acquisition!

Wishing you the best to make it yours, did the same on my present mount... it is rewarding as well, and well quicker than building :)
Running thru all the bulletins on Vans support page is a first step. Some of the updates are mandatory, others not.

Out of experience, assuming the instrumental panel is also targeted, plan enough time... I only wanted to exchange a couple of instruments on my previous non-RV homebuilt, and the result was nearly rewiring the entire plane. Good thing those Canadian Winters last...

PS
Guess a nice spinner is on the list ;)
 
HaHa...yes, winters can be long but today is supposed to be 18 C so it has not started yet.

Yes, spinner. As for rewiring, that is my intent anyways. I am comfortable with the electronics end (mostly) as my background is that. I am looking forward to that part.

Most of the instruments are coming out.

I thought I would post this to generate some input, and to add to great input I have already learned from other threads and personal conversations.

I initially planned/wanted a full glass panel. A quote I received even for a basic VFR GP was pretty much what I paid for the plane. Seeing as it is a fixer upper, and my first RV, I started downgrading my want list. I am now planning (open to amendments though) on keeping only the altimeter, airspeed and gmeter. Installing an AV30 (possibly 2), JPI EDM350 and using an ipad mini/forefllight to supplement (in a docking station).
 
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Looks like no matter how much fixing up you do, it will always look a little "RUF". :)

Congratulations on the new bird, and have fun modifying. That's what i've been doing to my -6 and it's been a lot of fun.
 
A quote I received even for a basic VFR GP was pretty much what I paid for the plane.
:D

I think you can still go pretty cheap using glass:
- I upgraded my steed with 2 experimental Garmin G5s, and those were pretty cheap methinks. Of course, adding my GNX375 upped the total price of my avionics...
- we just finished upgrading the RV-8 with dual GRTs, and also here, good results at an affordable price
- and yes, those moving maps on whatever tablet are amazing and affordable. My own everyday use iPad mini has been providing me, but for some hot weather in Nevada (despite the cooling cradle), with very good and reliable flight planning, weather and navigation data
 
Wing removal

That is the plan. I was thinking 2 G5's originally, then was chatting with a couple of guys that use the AV30. I like it a little better. Toying with one right now with space for a second but will evaluate after I get a better look at the rest of the plane.

I drained the fuel, disconnected the controls and have all of the nuts off the wing bolts. I think I am ready to try to get the wings off. We had a great weather day yesterday, working outside in less than a t-shirt . The next few days, more seasonal weather starts but at least I won't be crunched up in a freezing aircraft trying to hold cold wrenches and sockets.

Should I anticipate a battle to get the wings off? I am thinking that they slide straight out but cannot imagine that after 37 years in there, they will "just slide out". I also think that there will not be much "wiggle" to work with. Any tips here?
 
Should I anticipate a battle to get the wings off?

well, others might disagree, but yes, one normally battles... it's not the pulling out of the wings per se, but getting all the bolts out. The close tolerance ones have to hold pretty good, and they usually do... also I sure would install new ones when time comes to reassemble.

So, you might need a hefty hammer and some solid brass punches. Mark the joining plates position before removal.. they is usually some light engraving markings that were made by Vans or whoever was manufacturing those, but it is usually difficult to find and see.
Clamp the multiple layer spar together when removing the last bolts, and be sure to keep the wing aligned as installed until ready to pull it out. Tilting or changing its position, and then taking the bolts out, might damage the holes in the spar.

It can be done solo as I did during the build, and a few roller trestle with some wood planks protesting the wing is one way to do it. But the easier way would be to get at least another pair of hands.

Good luck, and looking forward to read your report :)
 
New to you 4

Congrats Shawn and welcome to the great world of RV flying. Come on down to Stratford CYSA, someday for a coffee. Maybe join the Windsor RVaviators Facebook group which is dedicated to RV flying here in Southwestern Ontario. Weather has been great and we continue to fly. Larger engine air dams.,oil cooler baffle , engine preheat, and ticker socks keep my -7 in the air many times well into December and sometimes past Christmas!
 
That is the plan. I was thinking 2 G5's originally, then was chatting with a couple of guys that use the AV30. I like it a little better. Toying with one right now with space for a second but will evaluate after I get a better look at the rest of the plane.

I drained the fuel, disconnected the controls and have all of the nuts off the wing bolts. I think I am ready to try to get the wings off. We had a great weather day yesterday, working outside in less than a t-shirt . The next few days, more seasonal weather starts but at least I won't be crunched up in a freezing aircraft trying to hold cold wrenches and sockets.

Should I anticipate a battle to get the wings off? I am thinking that they slide straight out but cannot imagine that after 37 years in there, they will "just slide out". I also think that there will not be much "wiggle" to work with. Any tips here?

I've had G5s and AV-30. Like the AV-30 better.
 
Sliding wings off

I did test the bolts today and they will all come out. When I was disconnecting things the other day, I found the inboard flap fasteners difficult to access. It seems the fuselage is in the way or I need a custom wrench. I am going to go over the build manual and plans again tonight to see if it hints at when control surfaces are installed. I would think after the wing is on, therefore, they should come off first but this morning, I was looking at the build manual online to see if the control surfaces were installed before or after the wing was one. It looks like it was before but not sure....

So, thought maybe I could just ask. The controls are disconnected in the plane. Flaps and ailerons are still installed on the wings. There are the 2 bolts (one in the front and one in the back/rear/trailing edge of the wing) just outside the fuselage but in the wing to remove and I think that is all that is left

Do I need to remove the surfaces? I am picturing a lot of effort required but hoping they just slide out. Any input? I wondering what getting a grip on it will be like.

Thanks Dan. I don't understand the "clamp" part. I think I need to look at the plans and construction manual more before I slide them out. It looks like they slide into a structure so not sure how I can clamp the spare..
 
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Thanks RV7guy2

I do plan on visiting Southern Ontario a bit when I get it flying. I have a few friends down there. Even in an RV, it is a 3-4 hour flight. I have done the down trip in a C150, up in a Tomahawk and to Montreal in a Warrior. Nice trips, all of them. The -4 won't be going anywhere before next spring, if I have a good winter of working on it.

mim
Congrats Shawn and welcome to the great world of RV flying. Come on down to Stratford CYSA, someday for a coffee. Maybe join the Windsor RVaviators Facebook group which is dedicated to RV flying here in Southwestern Ontario. Weather has been great and we continue to fly. Larger engine air dams.,oil cooler baffle , engine preheat, and ticker socks keep my -7 in the air many times well into December and sometimes past Christmas!
 
That blue…

I own a 94 -4 that I completely refurbed and modernized. My interior was painted that same hideous blue, It kept me up at night…I was never so happy when I repainted it. Used a flat gray epoxy primer, turned out great and is very durable. My apologies in advance if you are partial to the blue.
 

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The spar caps are made of multiple layers, thick and thin. The close tolerance bolts holding the joining plates are normally, and should be, hard to install or remove. If you have to hammer them out, a C-clamp holding the spar together at the top and another one at the bottom, next to the bolt you hammer out, best on the plates, will prevent damage to the spar.
Another point, some builders have to put some down (or up) pressure on the trailing edge of the wing in order to drill the rear spar hole to the required edge tolerance. This induces some twisting in the wing, and therefore removing the rear spar, and the tank bracket bolts first, is a good idea.

Control surfaces. Having them off will prevent damage to them, and the wings will be lighter and easier to handle. Take some pictures, or/and organize little bags for the hardware as you remove it, there might be some washers used for shimming on the ailerons. As for the flaps, easy, disconnect the rod and pull the hinge rod :)
 
lol....I too cannot sleep, sometimes for such concerns, and that has probably been one. That blue has to go! I never thought of just grey epoxy primer. Grey is what I wanted as well but wondered about primer, then paint, and keeping weight in mind. That small amount would not be much but I am trying to stay mindful of weight implications as I make changes.

Just E-primer is great with me!

Thanks!

I own a 94 -4 that I completely refurbed and modernized. My interior was painted that same hideous blue, It kept me up at night…I was never so happy when I repainted it. Used a flat gray epoxy primer, turned out great and is very durable. My apologies in advance if you are partial to the blue.
 
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Thanks Dan! That helps. When I was tapping on them yesterday, they were not easy to move, and the hammer I was using (brass capped head) was not large, but they did move so I feel good about the fit. It sounds to me the same as what you describe. That is all that I was checking yesterday. I have a better idea of what tools to take tomorrow.

The spar caps are made of multiple layers, thick and thin. The close tolerance bolts holding the joining plates are normally, and should be, hard to install or remove. If you have to hammer them out, a C-clamp holding the spar together at the top and another one at the bottom, next to the bolt you hammer out, best on the plates, will prevent damage to the spar.
Another point, some builders have to put some down (or up) pressure on the trailing edge of the wing in order to drill the rear spar hole to the required edge tolerance. This induces some twisting in the wing, and therefore removing the rear spar, and the tank bracket bolts first, is a good idea.

Control surfaces. Having them off will prevent damage to them, and the wings will be lighter and easier to handle. Take some pictures, or/and organize little bags for the hardware as you remove it, there might be some washers used for shimming on the ailerons. As for the flaps, easy, disconnect the rod and pull the hinge rod :)
 
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Wings off

Wing removal was successful! Dan's suggestion to use a c clamp worked great! Before I put the clamp on, I noted the layers that form the spar were separating and the bolts stopped moving. Other than that tapping, twisting, cussing, etc. seemed to work. I was not able to get the flap pin out while on the plane but once the control rod was disconnected inside, the flap did fall free, which allowed accessed to the rear spar bolt. Otherwise, it was very difficult to access.

In addition to using new hardware to replace the wings, I am thinking that reaming the bolt holes as per the build manual would be a good idea. I am wondering if wrestling the bolts free, if some galling of the aluminum plates may have occurred that may make installing more difficult. Anyone re ream after wing removal? Standard practice or not necessary? Can it do any harm?

Now to start picking away at a long list of items to address.
 
Spar bolts

The bolt holes for your spar need to remain as tight as possible, as the load transfer is reliant on zero gap between bolt and hole. Seeing that it was already bolted up once is proof enough it will go back together. The bolts come cadmium plated for corrosion resistance, and some of that gets peeled off during installation, which isn't a big worry for strength concern. I do heavy jet overhaul and modification for a living, often working with assemblies using bolts un-imaginably larger than the ones you are working with. I built my -4, and used the same principals as Boeing and Airbus use. I would recommend you simply tidy up the holes with small piece of ScotchBright taped to a piece of 1/8 or so steel rod and spun in a drill for a quick pass to get light corrosion ,ect. out. If you choose to use new hardware, pre-assemble the airplane with a dozen or so "stove bolts"of same size cheapo hardware from big box store and just put the nuts on finger tight. When you install the real bolts in the remaining open holes, mix up some epoxy primer and swab the holes (as you go) then immediately put the bolt in "wet". Properly installed close-tolerance bolts will require a little taping in..much better than if they just drop in. The primer will do two things, lubricate and protect from corrosion. The stove bolts will keep the layers from separating and because they fit "slightly sloppy" the NAS bolts will pull everything in line when they go in. Good luck..winter will pass fast and you have a long list!
 
As a former bolting engineer...

The bolt holes for your spar need to remain as tight as possible, as the load transfer is reliant on zero gap between bolt and hole. Seeing that it was already bolted up once is proof enough it will go back together. The bolts come cadmium plated for corrosion resistance, and some of that gets peeled off during installation, which isn't a big worry for strength concern. I do heavy jet overhaul and modification for a living, often working with assemblies using bolts un-imaginably larger than the ones you are working with. I built my -4, and used the same principals as Boeing and Airbus use. I would recommend you simply tidy up the holes with small piece of ScotchBright taped to a piece of 1/8 or so steel rod and spun in a drill for a quick pass to get light corrosion ,ect. out. If you choose to use new hardware, pre-assemble the airplane with a dozen or so "stove bolts"of same size cheapo hardware from big box store and just put the nuts on finger tight. When you install the real bolts in the remaining open holes, mix up some epoxy primer and swab the holes (as you go) then immediately put the bolt in "wet". Properly installed close-tolerance bolts will require a little taping in..much better than if they just drop in. The primer will do two things, lubricate and protect from corrosion. The stove bolts will keep the layers from separating and because they fit "slightly sloppy" the NAS bolts will pull everything in line when they go in. Good luck..winter will pass fast and you have a long list!

This is good advice.
 
The bolt holes for your spar need to remain as tight as possible, as the load transfer is reliant on zero gap between bolt and hole. Seeing that it was already bolted......, lubricate and protect from corrosion. The stove bolts will keep the layers from separating and because they fit "slightly sloppy" the NAS bolts will pull everything in line when they go in. Good luck..winter will pass fast and you have a long list!

Thanks fixnflyguy. Sounds like a good plan for me.
 
update

I made a bit more progress. Still just a matter of learning about what I need to do and ordering some parts for what I want and/or need.

I wanted lights and have now ordered all that I need from flyboyaccessories and ductworks to make that happen.

I have learned that I probably want a fully castering tail wheel and in my case, putting it into the hangar without one will be very difficult as it is now. I have also ordered those parts from flyboy.

I took some photos of a crack in the bubble. I was looking for a new one but a member here has steered me towards repair so I will be following up on that too.

I knew before I purchased the plane that the firewall was wrinkled. The seller pointed me to a thread on here to which I drew the conclusion that as much as it could be a large issue, it was most likely a small one. I was made aware of the heavier duty weldment plans made available by Van's. What I did find frustrating was that I could find no information or comments on Van's website about this newer version of weldment, only comments here. However an email to them yielded a quick reply explaining it. That reply is quoted below. There was a debate here as to whether the firewall was a structural part or not. I realize that some may agree or disagree with the information. For me, I just want to insure it is not an already weakened structure before I venture into less than awesome landings on a grass strip. I need to measure which version of weldment I have but I am suspecting the lighter version, ie earlier. I took some close up photos of the weldments, lower left and right. One thing I noted was that there appears to be a slight buckling in the lower left longeron (I think that is the angle piece in the photo. You can see the black oil spot whereas on the right, the skin is tight to the longeron. This may have been there since manufacture but I doubt it. So I could be in for a bigger repair than I had hoped. At this point, it is still research so that I have lots of reasons to lose sleep..... and order parts so that in the dead of winter, I have parts in stock.

The home renovation and getting an old hangar a little better prepared for winter is keeping me busy right now. I should be able to really get into the -4 in a few weeks. But, I am appreciating the input I am receiving this far, and learning a lot.

The other item I have been putting some time on is laying out the panel. Very preliminary ideas right now. I am using CAD to get a realistic idea of what fits and works where. As mentioned earlier, I have pretty much settled into 2 AV-30's, EDM 350, analog ASI and altimeter and gmeter. That should form most of the left half of the panel. On the right side, I am considering a dock station for an ipad mini for foreflight or a Garmin Aero660. I was hoping not to have a display mounted temporarily or strapped to my leg but the 4 is small. So now, considering planning on only one of them. Any thoughts on picking one of them or would most here find a way to get both in? Both will not go into the panel with the other instruments so it is kind of a one or the other for me right now. I have not used foreflight for flight yet, only in a Nav course I took. But it is talked about so much, it looks like a powerful tool to have. The AV30 uses an input from a GPS so that is why I am considering a 660. It may redundant with an ipad..?

I am thinking the Icom 210 and Sandia transponder may go into a tunnel mount. The intercom and ELT remote panel will fit in the panel. Probably a few things I have not thought of yet.

Any thoughts on those panel preliminary plans?

The response from Van's re firewall wrinkle in a -4 and the heavier weldments. With this email came the drawings for the newer weldments.

Shawn

I have never seen a published document regarding these weldments, maybe there was an article in the RV-Ator 40 years ago but this one never made it to service bulletin status.

The Key difference and easiest way to check is the thickness of the square plate that the bolt head rests on. Current production parts are .125 where earlier parts will be thinner. Simplest way to measure this would be with the depth gauge on a caliper as depicted below.

As for the firewall, all RV-4’s have wrinkles and most even have cracks at the lower corners. Key thing to remember is the thin stainless steel firewall is just that, a fire wall and is not a structural component.
 

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I made a bit more progress. Still just a matter of learning about what I need to do and ordering some parts for what I want and/or need.

I wanted lights and have now ordered all that I need from flyboyaccessories and ductworks to make that happen.

I have learned that I probably want a fully castering tail wheel and in my case, putting it into the hangar without one will be very difficult as it is now. I have also ordered those parts from flyboy.

I took some photos of a crack in the bubble. I was looking for a new one but a member here has steered me towards repair so I will be following up on that too.

I knew before I purchased the plane that the firewall was wrinkled. The seller pointed me to a thread on here to which I drew the conclusion that as much as it could be a large issue, it was most likely a small one. I was made aware of the heavier duty weldment plans made available by Van's. What I did find frustrating was that I could find no information or comments on Van's website about this newer version of weldment, only comments here. However an email to them yielded a quick reply explaining it. That reply is quoted below. There was a debate here as to whether the firewall was a structural part or not. I realize that some may agree or disagree with the information. For me, I just want to insure it is not an already weakened structure before I venture into less than awesome landings on a grass strip. I need to measure which version of weldment I have but I am suspecting the lighter version, ie earlier. I took some close up photos of the weldments, lower left and right. One thing I noted was that there appears to be a slight buckling in the lower left longeron (I think that is the angle piece in the photo. You can see the black oil spot whereas on the right, the skin is tight to the longeron. This may have been there since manufacture but I doubt it. So I could be in for a bigger repair than I had hoped. At this point, it is still research so that I have lots of reasons to lose sleep..... and order parts so that in the dead of winter, I have parts in stock.

The home renovation and getting an old hangar a little better prepared for winter is keeping me busy right now. I should be able to really get into the -4 in a few weeks. But, I am appreciating the input I am receiving this far, and learning a lot.

The other item I have been putting some time on is laying out the panel. Very preliminary ideas right now. I am using CAD to get a realistic idea of what fits and works where. As mentioned earlier, I have pretty much settled into 2 AV-30's, EDM 350, analog ASI and altimeter and gmeter. That should form most of the left half of the panel. On the right side, I am considering a dock station for an ipad mini for foreflight or a Garmin Aero660. I was hoping not to have a display mounted temporarily or strapped to my leg but the 4 is small. So now, considering planning on only one of them. Any thoughts on picking one of them or would most here find a way to get both in? Both will not go into the panel with the other instruments so it is kind of a one or the other for me right now. I have not used foreflight for flight yet, only in a Nav course I took. But it is talked about so much, it looks like a powerful tool to have. The AV30 uses an input from a GPS so that is why I am considering a 660. It may redundant with an ipad..?

I am thinking the Icom 210 and Sandia transponder may go into a tunnel mount. The intercom and ELT remote panel will fit in the panel. Probably a few things I have not thought of yet.

Any thoughts on those panel preliminary plans?

The response from Van's re firewall wrinkle in a -4 and the heavier weldments. With this email came the drawings for the newer weldments.

Shawn

I have never seen a published document regarding these weldments, maybe there was an article in the RV-Ator 40 years ago but this one never made it to service bulletin status.

The Key difference and easiest way to check is the thickness of the square plate that the bolt head rests on. Current production parts are .125 where earlier parts will be thinner. Simplest way to measure this would be with the depth gauge on a caliper as depicted below.

As for the firewall, all RV-4’s have wrinkles and most even have cracks at the lower corners. Key thing to remember is the thin stainless steel firewall is just that, a fire wall and is not a structural component.

Those look the newer firewall weldments. they may be the the .090 and not the .125 versions but I don't see any cracks that would worry me.
 
They are new style

Those are the more desirable "new style". Mine are the same, and you have dodged the bullet on needing to replace them. The old style weldments have separate vertical and horizontal legs that attach to the longeron, sort of fork like. The firewall wrinkles are in 75% of RV-4's if I were to guess. Lots of flexing down there. Not a significant structural issue. Some have installed a large triangular gusset between the longeron and the vertical angle of the firewall, but I cant find a picture of one, I am not sure if it was a VAN's recommendation or not. I have attached an old picture that shows my new style weldments. The uppers are similar.
 

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Firewall weldments

Thanks guys. That is interesting. I just went through the log book again to see if the new style had been documented as installed and there is no documentation. Seeing as this is a 1985 model, I am surprised that these are the "newer" style which I thought were circa 1995 ish...

With the plane, I got a large binder of the old RVator newsletters so may try to find a reference to weldment changes that the builder may have incorporated into his build. There could not have been many flying at that time though since the kit had only been available for 7 years?

I did note two things. The paint on the bolt on the left one looks like it has been either removed and reinstalled or has shifted. Perhaps not torqued correctly? The right one shows no such paint break.

In the upper left, there is a very minor looking crack. It may be paint only and appears not severe, just something to investigate more when the fuselage is here in my shop.
 

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The large bolt/engine mount

The large bolt is as you probably know, the engine mount attach bolt. Most are done with a drilled bolt, castle nut and cotter pin, which may be was "turned back" to get the cotter pin in, thus slightly loose. I installed mine with 12 point tension lock nuts. You can simply re-torque yours most likely. I'd dye penetrant inspect that suspected crack. At least who ever built yours did a pretty nice job of spacing the fasteners in the weldments..some I've worked on are horrible swiss cheese looking disasters.
 
..... may be was "turned back" to get the cotter pin in, thus slightly loose. .....You can simply re-torque yours most likely....... I'd dye penetrant inspect that suspected crack. At least who ever built yours did a pretty nice job of spacing the fasteners in the weldments..some I've worked on are horrible swiss cheese looking disasters.

Thanks. You bring me positive hope....:)
 
If you have the opportunity to pull the engine mount off (which if you need to replace the weldments you will), firewall cracks can just be stop drilled and sealed with an appropriate firewall sealant. I used a tube of 3M fire barrier caulk from the aviation aisle at Home Depot. You can opt to replace the lower firewall but it will just end up cracking in the lower corners again; it’s a design flaw that everyone has just come to live with.
 
"The wrinkles"

The wrinkle will appear in the lower half of the firewall/footwell usually just above the lower engine mount bolt and some "oil canning" can occur. There is a load of flexing going on with landings that can cause them in the soft stainless firewall. It has relatively zero structural purpose, and the load is carried through the engine/gear mount and the stiffeners behind the firewall. See attached picture..not mine, but they are abundant.
 

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My wrinkle

This is the wrinkle photo I received from the seller back in the summer. After reading about it, and knowing I was buying a project, I went ahead with the purchase.
 

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google

Thanks Dad's RV-10

I would have thought that the site search would be better, localized. Obviously, wrong again. :rolleyes:
 
I wouldn’t give the minor wrinkles in the firewall another thought.
If the lower mounts are the thinner version you can add a .050 doubler on the outside. Replace the rivets one at a time with structural screws.
Only worth considering if you plan to operate regularly from sod.
 
I wouldn’t give the minor wrinkles in the firewall another thought.
If the lower mounts are the thinner version you can add a .050 doubler on the outside. Replace the rivets one at a time with structural screws.
Only worth considering if you plan to operate regularly from sod.

Yes, I will be flying off of a grass strip. And a relatively low time tail wheel pilot....

:eek:
 
Panel fun

I have been playing in FreeCAD to layout the new panel. It is based on what I am keeping from the old panel and what I am planning to purchase. I have looked at several RV4 interiors on line and seem to like the switches and circuit breakers on the right side of the pilot versus in the panel. Some guys have done a really nice job with that so I hope to get close to what I have seen. Therefore, I have not left room for switches in the main panel. I have also seen some panels slightly taller and some with a panel added to the bottom of the normal size panel which contains the electrical switches and or breakers. All seem good options. Each to his own. I wonder if the extended bottom would make entry a little more difficult as I get older...? I will play with that when the plane is in the shop but for now, limited to planning with the standard size panel.
The attached is preliminary. Exact locations, ie to the 0.001" is not done but the general layout is appealing right now.
Please let me know what you think or notice if I am missing something. I do not have a slip indicator as the AV30 AI has it. With that in mind, the old style compass may be redundant but it gives me comfort. I am not sure of regulations if the AV30 satisfies all requirements. I guess it does as it takes care of everything else....

So, since we all like looking at, planning and discussing panels, have at it...

Cheers,
Shawno
 

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A crude albeit better than lines version of it the panel proposal.

I just heard about hangarflying.com so might go play there sometime. This serves my purpose now, which is to see what fits where. I might need some warning lamps like Canopy not latched and electrical fault. There is lots of room to get those in.
 

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wonder if these standby instruments are still necessary... if in clouds, the only vital thing is a horizon, outta clouds no instruments work good if one learned to fly rear seat, on a J-3 Cub, with a tall and wide CFI in the front seat :D

That's only me of course ;)
 
Mount Pix

+1.
With 2 AV30’s and a backup 6 pack available on the Aera, the steam gauges are clumsy left overs. FWIW I have experience behind the AV30 and the G5. I much prefer the readability of the G5.
To revisit the lower engine mount: here are a couple of pix of my short geared -4 that was built in ‘87. The logs show a new firewall and engine mounts in the late 90’s due to wrinkles and cracks. The beefing up extends beyond just replacement of the mounts with the newer version.
D534AB07-9C16-4F1A-A880-47F2B6751E31.jpeg

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Reconsidering panel ideas

Good points Dan and andoman. Thank you

I have not flown behind a digital flight instrument. What are they like for aerobatics? I was thinking that the ASI would be easier to read and may respond more quickly than a G5 or an AV-30. I also wonder how easy it is to read in those situations but I suppose that like anything, one gets accustomed to it.

Good point on the Aera 660 6 pack feature. Again, I never thought of the Aera as a back up flight instrument, but rather just a GPS. I underestimated it. So, since the AV30 can be both AI and HI, should the AI fail, I could switch the HI over.

So, yes, lots of redundancy. That was not my sole purpose. It was more to have a quick reference for airspeed and a backup for the AV30 Attitude indicator. But, obviously, I have lots to learn. For those that fly only behind a G5 or AV30, ever wish you had an analog ASI?

Thank you for the input. I may reconsider the extra instruments.
 
To revisit the lower engine mount: here are a couple of pix of my short geared -4 that was built in ‘87. The logs show a new firewall and engine mounts in the late 90’s due to wrinkles and cracks. The beefing up extends beyond just replacement of the mounts with the newer version.

Thank you.
 
What are they like for aerobatics?

No problem at all... in opposition to mechanical instruments, they don't tumble.

Now this is your machine, and we will respect your tastes and whatever the panel will be when done :)
And I therefore won't try to influence you...

On the following pic, the VFR only panel as it was when I bought my -6.9, and today, with IMC capability. The components:
- dual battery back-up expensive version G5s. "Cheap", easy to install (a little bit more if you wanna have wind and OAT), light, highly readable
- battery backed-up AV-20, in case of G5s failure, could be due to software (...) or other reason. Note, no speed readout on this, but AOA
- the expensive bit, the GNX375 navigator, worth it's weight in gold (don't tell Garmin lest they increase it's price even more)
- and the good 'ol VM1000 engine monitor, still working good

The whiskey compass was removed (either G5 will provide TT assuming the magnetometer is lost, and so will the iPad mini and the iPhone), and none of this AP stuff installed. I now have >1K hours behind this panel, and perfectly happy. All I need, and none of those acres of glass that most seem to fancy (and afford) nowadays...

For slightly bigger and cheaper screens I would consider dual GRTs, just installed them on the -8, and though I haven't flown them yet, they look good.
 

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My panel

I built my -4 with a "steam panel" when glass was something you drank out of. After years of fighting the movement, I installed a G5, mainly because I never had an artificial horizon, and I liked the costpoint of the EXP G5 ($1200) vs the more expensive options. I retained all my other steam gauges and I'm still more conditioned to using them, however the G5 has most everything in it and reduces the normal panel scan. My test flight with the sun directly on it (RV-4's are bright inside) verified the instrument is still easy to see. I had and antiquated mini GPS that I removed and put the G5 in its place, as I prefer my knee pad Nexus tablet or my Android phone with free AVAR for GPS use. Maybe someday I'll do the big glass, but I cant handle the $$ for that at this point in life, nor does my mission require it. As for the quick turs/acro, the G5 hangs in pretty well ( I never stare at the panel doing acro)and even with the mGMU11 magnetometer in the tail and the G5 aux GPS antenna it will get a heading flag on occasion, but that goes away in a second or two. Since I'm all VFR, that doesn't concern me.
 

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I come here for infuence...

Now this is your machine, and we will respect your tastes and whatever the panel will be when done :)

And I therefore won't try to influence you...

On the following pic, the VFR only panel as it was when I bought my -6.9, and today, with IMC capability. The components:
- dual battery back-up expensive version G5s. "Cheap", easy to install (a little bit more if you wanna have wind and OAT), light, highly readable
- battery backed-up AV-20, in case of G5s failure, could be due to software (...) or other reason. Note, no speed readout on this, but AOA
- the expensive bit, the GNX375 navigator, worth it's weight in gold (don't tell Garmin lest they increase it's price even more)
- and the good 'ol VM1000 engine monitor, still working good

The whiskey compass was removed (either G5 will provide TT assuming the magnetometer is lost, and so will the iPad mini and the iPhone), and none of this AP stuff

Thanks again. I appreciate a bit of "influence"..I see it as guidance as I dive into this new phase of aviation (building/modifying and flying an RV ) :) I come here to learn from the experience of others that have been using this equipment for longer than I have.

If I can simplify the panel and still feel good about it, I am all over it. After reading these posts last night, I started eliminating instruments in my panel layout (CAD) that are overly redundant and experimenting with placement of an ipad mini. There are threads here on locations for the ipads. I figure that even if it is not mounted in the panel, if I have a clear area in which it can over lap via a RAM mount, then that is another tool I can add mostly to support foreflight.

I like your flush mounted G5's look! Very nice. I like the AV30 for the flush mount but round look. It incorporates AoA like the AV20 does.

This guy does a pretty good overview of using an AV30 .

I would be happy with either of your panels.

Much appreciated.
 
....when glass was something you drank out of. After years of fighting the movement, I installed a G5, mainly ..... the G5 has most everything in it and reduces the normal panel scan. My test flight with .... verified the instrument is still easy to see. ..... but I cant handle the $$ for that at this point in life, nor does my mission require it. As for the quick turs/acro, the G5 hangs in pretty well ... Since I'm all VFR, that doesn't concern me.

Thank you.
When I was waiting for delivery of this plane, I was all over installing a full glass panel, IFR capable, blah blah blah. I am not IFR certified yet, although considering it this winter. Time for it might depends on management's renovation schedule for me ;) and how the RV makeover goes. Once I got pricing on the full panel, I started reconsidering it. I have decided to do, what I consider, a nice VFR panel and see how things go. Maybe in the future, I will upgrade to either IFR panel, but more likely a plane in which it is already done.

So kinda the same boat as you. Practicality drives upgrades.
 
Version 3

Because I like playing with CAD and Paint, here is another option based on the last few posts.

I like it better already. The ipad will come out after every flight and might not go in for every one, depending on what I am doing. With the Aera660, it will be in for most flights, I would imagine, hence the in panel mount. Much of my flying will just be around the local area but I have aspirations of doing more cross country stuff in which I will want both foreflight and the GPS.

Anyone see anything else that I may want to include in the panel?
 

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Shawn,

If it were my airplane, I would move the compass to the left and put a purely pitot-static round dial airspeed indicator in its place. That way, when the electrical smoke cleared and all the screens were black, I'd still have indicated airspeed. A non-electrical AOA indicator could substitute.
 
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