Empennage Completion... CHECK!

Hi Gang! Over the last two days I've been working to finish the empennage. By finishing the second elevator trim tab today, I've completed all the metal parts of the emp. I still have some fiberglass to do which will probably be done towards the end of building and before paint. I'll have to go back to torque a few things and put torque seal on the nuts. I may have to work with the counterbalance weights to get the balance of the elevators right. They seem fine now but we'll see how they do after all fiberglass work and paint is done.

I learned a little tip tonight by experimenting with needing to dimple a hole that was very hard to get to. First, I inserted a block of wood under the hole that needed dimpling. Next, I drilled a #40 hole into the wood. Second, I took the block out and gave it a little camfer to the hole with a deburring tool. Third, I took the block and re-inserted it under the hole, then took the dimple die and inserted it into the hole then hit it a couple good whacks with a ball peen hammer. It's not identical to a normal dimple but it worked pretty well. The reason for this process is that the back side of any of the dies I had, including the pop rivet die, would have interfered with the inner tabs that fold down and damaged one. Below are the pictures showing the steps I used and a couple showing the comparison of both trim tabs. I'm pretty happy with how the second one turned out. I think it's much cleaner. Remember, you can click any of the pictures to enlarge them. :)

Setting Blocks for Drilling/Dimpling

Hole Drilled Into the Block

A Little Countersink with the Deburr Tool

A Couple Whacks with a Hammer and ....

VOILA! A Dimpled Hole

Top is the First Tab, Bottom is the Second.
The Back Side was Actually worse on the First.

I'm now ready to call one of the EAA chapter tech counselors to take a look at my work and give me either a thumbs-up or a list of things to fine tune, fix, clean up or repair. We'll see how that goes and I'll keep you posted on that report.

I recently purchased and received the parts for the RV-7 Service Bulletin 14-01-31. In the empennage, more specifically, the horizontal stabilizer (HS) some builders/owners have shown an area on the that has exhibited cracking. A service bulletin came out warning of the issue and a kit was made by Van's to repair the issue for those that are already flying or currently building. It's about $15 +shipping. For those that are building, this can be used to repair the are of potential cracking they might currently have, which I would guess is doubtful, or they can use it in the future, should any cracks show up. I am going to repair mine before completing my plane as I'd like to have the corrections made before they even have a chance to happen. Right? It makes better sense to repair now so you wouldn't have to disassemble your plane in the future. This will save a lot of time and give me a greater feeling of safety and security. I'll probably save this little project for sometime when I have any lulls in the project. I think it'll make good filler.

Van's RV-7(A) HS Repair Kit
Service Bulletin 14-01-31

Here's a glamour shot of the completion of my empennage and me in the picture to let you know who the builder of this project is.

So Relieved to Have This Kit Finished! Wings Next

That's all for now. Take Care and Thanks For Reading!!

Day Total: 2.6 hrs  HOBBS Meter - 160.9 hrs

Let's Get This Thing Going!

Hi Gang! I'm finally back at it after much procrastination. I had previously spent about an hour working on the elevator in preparation of getting it welded, as mentioned previously.

I discovered that a friend of mine at work is a skilled welder. I got in touch with him and asked if he could weld some airplane parts. He asked when I wanted to do it and what kind of metal he needed to weld. I asked what kind of liquid payment ;) he would like and we hooked up and got it done. Thanks Mike! I've been waiting for a good time to start back up and now seemed as good a time as any. I didn't get any pictures of the welds before cleaning and filing.

Today I cleaned up the welds on the fills Mike did for me. I needed to file down the excess weld material to get them back to smooth and flat. After the filing, I cleaned up the surrounding area of powder coat that was damaged by the heat of the welding with a ScotchBrite wheel in my Dremel. All pretty now.

Weld Filled Hole After Filing & Cleaning

Back Side

Next was to make sure my rod bearings were the exact height they needed to be. I think I took care of this previously as when I checked the bearings on both elevators, the height measured right on all 4. I mounted them both, set them in trail with the HS then eyeballed how the 1/4" bold would appear to fit and it looked good. So I took the right elevator off, put the drill sleeve into the hinge bearing and drilled a #40. So far, so good. I took the left elevator and put the right one on and did the same thing. Off with that one and put the HS away so I could work with the elevator horn holes. This is the same procedure as mentioned in a previous post. Just size the holes up with each successive drill bit until it's 1/4". I cleaned the holes with a half round file so a bolt would slide easily and cleaned the surrounding area of any sharp metal. I put both elevators back on and put the bolt in and VOILA! Everything fits & both elevators line up perfectly. Nice smooth movement with no binding. They seem pretty balanced right now. I still need to file the counterweights to the right shape so we'll see how the balance is later. I'm very happy with this.

NOTE: I strongly recommend to the builders out there that are at this point and before drilling to check carefully to see if your bolt appears that it will fit WITHOUT the bolt head and nut being to close to or interfering with the torque tubes. If it looks too close, recheck your measurements on the rod bearings.

The Line Up & Clearance After Installation

After taking everything apart, I then started working to finish the 2nd trim tab that I had ordered awhile back and had just started. I'm about half done with it now. I'm almost to the riveting stage. Just finished the countersinking in the trim spar. I'll pick up there next time.

That's all for now. Take Care and Thanks For Reading!!

Day Total: 3.9 hrs  HOBBS Meter - 158.3 hrs

Still on the Empennage

Hi Gang! Yep, I'm still working the empennage. I never made it out to the welder to have my elevators' holes welded. I just can't afford it right now. Yep, money is that tight.

 

In the meantime, I decided to start working on the replacement trim tab. It's the same steps as before, but this time, I followed the plans more precisely. This time, I scuffed, cleaned and primed the areas where the end tabs will be bent as well as where the spar sits. I clecoed the bottom of the spar to the bottom of the tab skin and also put the trim tab control horn in place as well. I used the 2 horn pieces that came with the kit originally. Those have to be trimmed down a bit as there is a little extra on them. That's if you're using the manual trim I believe. Anyway, I match drilled all the holes on the bottom. Next I will remove the old trim tab from the left elevator and use the hinge as a guide for cutting the new hinge. I'll keep the old tab for a replacement, if I were to ever need it in the future. It's not in bad shape, it's just not perfect! Haha. I'm stopping here for tonight so I can get ready for the work week. No pix as it's the same stuff. I just hope this one turns out better.

Take Care & Thanks For Reading!

Day Total: 2.4  HOBBS Meter - 154.4

Trim Tab Complete!

Okay, okay. I may have been a little harsh in my previous post regarding builders being overly picky and meticulous when it comes to the trim tab. I know that I'd like the perfect plane, in every aspect. Those little blemishes that occur along the way are what make our planes ours and very unique to us. I had much more difficulty with my trim tab than I'd expected. I think the issue is that the directions could be written a bit better with regular updates. Maybe this isn't the most cost effective way to do things at Van's, but it would help builders who succeed us with less headache. For instance, particularly on the trim tab, noting what areas should be dimpled and countersink BEFORE even bending the trim tab would be MOST beneficial and save on some time and aggravation. I know it would have for me. Ask me how I know this. Maybe I should start reading the sections entirely before embarking on a part. At times this isn't feasible, such as when you read before you build, sometimes it doesn't make sense as you're reading.

Masking for Priming Before Riveting Horns

Notice Anything? Yep, I Forgot to DIMPLE!
This Also Shows Rivet Sizes for Different Holes

Previously, I deburred, dimpled, countersunk and primed all the trim tab parts. I started with clecoing the trim tab back together. The directions tell you this then to rivet the bottom of the skin to the bottom of the flange and the trim tab horns. Well, you can't entirely cleco the trim tab and accomplish this. I needed to leave the upper skin unfastened to get either a squeezer or a bucking bar in the space. I riveted the horns and flange all in place and only had to rework 3 rivets.

I don't think I followed the directions in the right order but I basically got the hinge positioned in the previous steps, drilled and clecoed to the trim tab. Next, I positioned the trim tab on the elevator and marked the hinge position on the elevator laterally, figuring about 1/8" between the bent tabs areas. Next, I removed the forward part of the hinge and clamped it in place on the elevator. I started drilling on the outboard hole, then cleco, then drill every other hole, cleco then went back and finished drilling the rest of the holes. Next was marking the inboard skin edge on the hinge then trimming that area to match the skin when installed into position. I clecoed the forward part of the hinge back on the elevator and connected the trim tab with the hinge rod. Once this is in position, I used a small squeeze clamp to hold the trim tab in line with the elevator. This step is where alignment is needed to get the tab to follow the line of the trailing edge of the elevator and to tweak the tab to get it straight and follow the same line on the up and down axis. Per the directions, I clamped a piece of angel aluminum to the trailing edge of the elevator and aligned the tab to follow the same line and angle. Once it was straight, I put the clamp in position to hold it to the elevator then drilled the three #30 holes for the pull rivets on the bent tabs and put a couple clecos in. Next, I carefully removed the hinge rod and riveted the top of the tab with the hinge in place. After that, I put the pull rivets (CS4-4) into the bent tabs. Then I needed to figure where the rivets would go on the other end of the trim tab so as not to interfere with the rivets needed on the elevators bent tabs. I put the trim tab back on to mark where I would put those rivet so they were offset from each other.

Setting Position for Tweaking the Trim Tab

Marking Bent Tab Area for Pull Rivets

Next, I riveted the forward part of the hinge elevator and VIOLA! The trim tab is is done!!! Directions tell you that the pin/rod for the hinge is not long enough and that you'll get one that fits the way it should for bending and positioning in place to be wire tied to the elevator. That one will come with the fuselage kit. I need to make a punch list of things I need to go back an complete. Up to this point, there hasn't been much. Things like this hinge rod, torque sealing certain nuts and bolts as well as any other things that don't get checked off the direction list right away.

Trim Tab Complete, Except for the Hinge Rod

Another Shot of the Completed Trim Tab

I agree that the trim tab is very small, but a major pain in the @$$! It does take patience. If you're getting frustrated, STEP BACK, TAKE A BREATH! Just go slow. This thing doesn't and WON'T be done tomorrow, at least not at this stage. While riveting my hinge to the trim tab, I didn't have my squeeze set right and bent one of the hinge sleeves. That took 10 minutes or so to get worked out. But turned out fine. I put another marred spot in the skin while bucking one of the hard-to-get-to rivets. The bar was set funny inside and I didn't have the rivet gun on very well. Needless to say, the skin is quite ugly in that spot.

The Marred Area From the Bucking Bar

The Same Area, Different Angle. It Has A
Tin Can Effect if Pushed From Both Sides

If it turns out that I'm just not that happy with it, maybe I'll make another later. It's pretty straight and true. I saw another builder talk about the flange inside not being very well fabricated and it causing one side of the skin to bow when pulled into position. Mine is doing that as well. There's a bit of a bow on one side and pretty straight on the other. I'm going to leave it alone for now.

I semi-installed the trim tab motor to get a feel for how the push rod will be positioned when it's in it's final position. There will be some trimming needed for clearance where the rod exits the elevator skin. It shouldn't be a big issue, a little fine trimming, filing and cleaning. I'll probably work the fiberglass tips later with the other fiberglass. I want/need to take the fabrication course that the EAA offers (SportAir Workshops) before I venture into uncharted territory. I'm not sure if I'm going with the seamless look or screwing the tips on. The latter gives better accessibility for any fixes, changes or repairs. The seamless gives a nicer look as well as better waterproofing for the inside of the wings and empennage. I'm going to weigh the options and read what VAF members and other bloggers have done to see what the consensus is. Next will be rolling the leading edges of the left and right elevators. Fun stuff... NOT! Well, it kinda is. =8^P

That's all for now. Take Care & Thanks For Reading!

Day Total: 5.9  HOBBS Meter - 141.8

... and the Building Resumes!

Sunday, July 28

Finally, back to work! Today, I started back on the trim tab. I put it in the bending brake last session and I went too far. I tried carefully to bend it back out, no easy task. I managed though. There are a total of 4 tabs (2 on each end) that require bending 91°. Make sure you pay close attention here. The lower tab is bent FIRST, then the upper tab. This way, you won't get water leaking or draining into the tab in the rain. When you start this process, the plans show you starting with the whole trim tab upside down. It makes it a little confusing. In this case, you bend the top tab (lower) down first, then the bottom (upper) tab up second. You'll get the picture with the inboard section as there are 3 rivet holes on one tab that need to be on the outside when finished bending. Do both ends the same. I read of many builders ordering an extra trim tab set just because most use the first one as practice and aren't happy with the outcome. C'mon! It's just a trim tab. Once it gets sanded, cleaned, primed and painted, I don't think they really turn out that bad. I know, there are some perfectionists out there. I'm one too. You can always order a kit later and do it again if it's really that bad. I think mine turned out pretty well. I may have bent a little too much of the tabs on one end, but I think it'll be fine.

Outboard End of Trim Tab, Decent Bending

Inboard End of Trim Tab. A Little Too Much Metal Bent

Basically, I took a piece of 1/2" particle board about 7"x3", figured the angle of my trim tab with the spar in place, which is right about 10°. Then I cut it at that angle. I'm not too fond of my small, cheap, name-brand band saw's ability to cut a nice, straight line. So, I used a piece of 1/4" metal, used for my dimpling in tight spaces, and clamped it to the board on the angle of my cut and used a small hand saw against the edge of the metal and made a real nice cut. In retrospect, it doesn't matter what angle it's cut. Basically, it just needs to be greater than 10° but less than that which would open the trim tab up too far. You can use the distance that when the end tabs are bent, they're separated by 1/8" to 1/4". If you follow the 10° method, make sure to leave a small enough angle at the trailing edge to fit into the space of the trim tab. I used double-sided Scotch tape on both sides of the inside block and a strip on the outside for the outer block. This keeps things mostly in place. I should have put the whole assembly on a non-slip piece of mat on top of the work surface to prevent slipping but it "slipped" my mind. Haha, bad joke. Another thought would also be to use some tape on the work surface to hold the entire trim tab in place. I clamped the whole block assembly to the bench with ratchet clamps as well as clamping the trim tab on the leading edge to the edge of the work bench. Let the bending commence. You want to turn your pressure down on your rivet gun so you don't go too wild and bend the crap out of the tabs. Use a block of wood to get started on the bend, per the plans. Once you get the tab closer to its final position, you can use just your gun to flatten it out pretty nicely, all along the edge, back and forth until you're satisfied. Yes, you'll notice here that this is the same exercise used on the left elevator. I previously used foam tape. BAD idea. Don't go this route. It's is too thick and gives too much and is a royal pain to remove from your jig parts. It was a bit overkill. Just follow the directions for preparing and you should do fine.

Next, I cleco'd the trim tab spar (E-607PP) to the bottom surface of the tab skin. Then I got the electric trim tab motor trim tab horns (E-617EEPP-1 and E-618EEPP-1), clamped them together, used a clevis pin in the holes for alignment and clecoed them as a whole part to the skin. Needed are a couple holes drilled for one of the horn parts as the skin is without. That's why it's necessary to clamp the 2 horn parts together, using them as a template, of sorts. Pretty simple here. After fitting the parts in place, I match drilled the holes through the trim tab horns.

Spar in Place

Elect. Trim Tab Motor Control Horns in Place

Another View of the Trim Tab Horns Connected as One

I stopped here for the night as the next step is working with the piano hinge. I wanted to do a little research on this one. I'd certainly like to get this right on the first try.

Day Total: 1.9 hrs  HOBBS Meter - 132.2 hrs

Tuesday, July 30

Tonight, I started working on a few bends and dings that mysteriously showed up on the leading edge of the left elevator. Okay, I'll confess. I had put the elevator up out of the way, hanging the counterweight end on one of the rafters. I had the garage door open half way for air and later decided to open the door all the way. I wasn't paying attention and the door pushed the elevator off the rafter and bent a couple of areas along the leading edge. So, I took a little time to straighten them out. The edge hasn't been rolled yet, making it pretty easy to ding the edges up a bit. I was able to straighten the worst offenders pretty well. There were only about 3 or 4 issues. The elevator itself looks pretty straight and true so I don't anticipate any issues with it later. It'll be interesting to see the leading edge after it's rolled and riveted. I'll try to post a couple pictures after the roll.

The Smallest of All Dings. Needs a Bit More Work

Ding #2. I Hope This Cleans Up Better After Edge Rolling

Ding #3 More Outboard of #2

The Top of Ding #3. I Hope This Ends Up Rolling Ok

Next on the list was to work the hinge for the trim tab. I checked a couple other builder logs for info. Interestingly, the few I looked at didn't have much in the way of information. So I decided to follow Van's plans the best I could. Sometimes they can be a bit confusing. I have a habit of over-thinking things at times. It took me a while to comprehend that the hinge DOES NOT go between the skin and spars. I don't know why I had this in my head, but once things "clicked", it was much easier to move forward. Over-thinking I guess! The hinge rivets to the innermost area to the skin and spars.

Hinge Measured, Marked & Clamped in Place

Showing 3/8" From Rivet to Inboard Hinge Edge

Trim Tab Hinge Drilled & Cleco'd in Place

I started by marking the hinge at 1/4" in from the trailing edge of the trim tab side of the hinge the length of the hinge. I did the same for the elevator side as well. This line is used as a site line through the rivet holes for alignment and distance. Then, I made a mark on the hinge for the area that would be removed (waste) on the inboard edge. That distance is 3/8" from the left-most rivet hole to the end of the hinge on the trim tab side, per the plans. After trimming the hinge, I clamped it in place on the bottom of the trim tab spar, making sure the site line is centered in the rivet line. Then I match drilled the holes starting with the inboard hole first, clecoing it then drilling every other hole and clecoing while removing the clamps along the way. Then I went back to finish the rest of the holes. I then put the other half of the hinge back together with its mate. The next step is to take apart the trim tab assembly, machine countersink the spar and dimple the trim tab upper holes and work more on the control horns. Stopping here tonight.

Day Total: 2.0  HOBBS Meter - 134.2

Wednesday, July 31

Tonight saw drilling the rest of the holes in the trim tab, countersinking and dimpling the trim tab spar. Next was to disassemble and the usual "Lather, Rinse, Repeat" with deburring, dimpling and priming. Not too much tonight, just enough to keep busy on the project, KPR! (Keep Pounding Rivets), and... edge finishing, deburring, dimpling and priming. KPR for short. =8^)

That's all for now. Take Care & Thanks For Reading!

Day Total: 1.7  HOBBS Meter - 135.9