July 28th, 2013 - Working on the center cabin and fuel valve covers.

I started this post over a week ago and then never got around to finishing it.  Just realized it wasn't finished when I went to start on the one for this week.

 This week I was working on the center cabin cover, the fuel pump cover, and the fuel pump valve cover and plate. For once, this whole thing is pretty basic and doesn't have much in the way of surprises. The center cover will cover the fuel and brake lines. The fuel selector is on top of a short pedestal mounted to the front spar. The fuel lines run from the left and right tanks through the selector and forward under the center cover. Brake lines are from the mains, which are on the outboard forward side of the spar.

Before I got started I deburred the parts and clecoed everything in place to make sure I understood how it was all supposed to go together and that it seemed to make sense.

From Fuselage

This is the plate where the fuel selector will go.  The angled forward part is where the elevator trim will go (mine will be manual).

From Fuselage

Installed the nutplates in the fuel selector cover.

From Fuselage

More nutplates in the center cover.  The cover is laying on its side - it is L shaped, and part extends vertically up the firewall.  The part to the right is where cabin heat will enter the cabin.  Below will be the fuel pump, which gets mounted on the firewall.  There is an access plate that covers the fuel pump, which is what all the nutplates around the open square area are for.

From Fuselage

Once all the nutplates are on, I fit everything back on and screwed it down to make sure the alignment was correct.  Once it's right, the center cover gets shimmed to the correct height, then match drilled.  Nutplates are installed to make it secure yet removable.

From Fuselage

I made up some shims from some scrap wood.

From Fuselage

Center cover shimmed and installed to the correct height.  I made up a drilling template to put the drill bit at the correct height and make sure it didn't move on me.

From Fuselage

Installing nut plates on the center cover.

From Fuselage

Center cover is done except for priming.  Next week I'll start on the flap stuff.

July 21st, 2013 - Priming and riveting the seat backs.

Finished up the seats this week.

I finally remembered to take some pictures while priming.

With the weather (raining when I need to paint) and other commitments,  I usually end up finishing parts up to riveting stage, then going on with the next thing until I can get them primed.  By the time everything comes together, I can have a pretty big pile of parts backed up.

For this batch I had all the seat parts plus some baggage compartment covers.  I wish I'd thought to do the flap cover and fuel/center covers, but I didn't.

Basically once everything has been cut to length/machined, match drilled, deburred, dimpled/countersunk (if necessary) and everything else, the last thing to do is prime the parts then rivet them together.  Sometimes I'll get everything up to drilling (like in the case of the right seat) and prime it first, since it won't be exposed to any weather, drilling after priming is no big deal.

Priming is pretty simple although it takes a while (2-3 hours) with all the prep/setup, waiting for the paint to "cook" (it's a two part epoxy primer), then spraying it, cleaning everything up, then tearing it all down and putting everthing away.

Once all the parts are ready, I go over them and make sure all the parts are scuffed up, then clean them several times with MEK or Acetone, followed by alcohol.

Pile of parts ready and staged for priming.

From Fuselage

I paint outside in the side yard.  Since it's not a finish coat,  the dust really isn't an issue, and the epoxy is not something you want to breathe.  I use my sawhorses and a bunch of large pieces of cardboard to support the parts.

From Fuselage

I also wear long sleeves and a solvent respirator.  The epoxy is kicked off with something that looks/smells like MEK, which is some pretty nasty stuff.

From Fuselage

I use a cheap HVLP gun I got at Harbor Freight aircraft supply at Tim Ribble's recommendation.  It does a really good job for under $40.  If I'm careful I can get a pretty nice finish.

From Fuselage

The epoxy primer came from Aircraft Spruce - AkzoNobel two part.  If you look inside nearly any Boeing aircraft, military or civilian, you'll see this stuff.  Expensive, but tough as nails and dries super fast.  It's mixed 1 to 1.

From Fuselage

I tried a few measuring ideas before I hit on this stainless ladle.  It's perfect, just hide it in the garage so no one uses it for cooking.

From Fuselage

Mix the paint in a mixing cup, then let is simmer for 30 minutes.  The pot life is really good - you've got several hours, which is amazing cause once it is sprayed it literally dries almost as fast as you can paint.  I can turn parts over in 5 minutes. They are stackable by the time I'm done priming and starting to clean up.

From Fuselage

Batch of parts after priming.  Mostly seat parts, but also some miscellaneous parts from the baggage compartment and rear fuse.

From Fuselage

Seat backs and baggage compartment covers after priming.

From Fuselage

Once I had everything primed, it was finally time to nail the seats together.  There are a lot of parts that have to be clecoed together.  It turned out I could use my  pneumatic squeezer w/the Longeron yoke for nearly everything, I just had to clamp it in such a way that it was easy to get to.  Most of the rivets (actually all of them come to think of it) are AN470-4 round head.

From Fuselage

Working on the left seat.  The piano hinges are the attach points to the floor and bulkhead.

From Fuselage

Here's the completed left seat riveted and installed in the fuse.  Really light (< 5lbs) and very strong.

From Fuselage

Here's a side view.  I haven't cut the hinge pins to length yet.

From Fuselage

Working on the right seat back.

From Fuselage

Both seats finished, hinge pins cut to length, bent and installed.

From Fuselage

View of the seats looking aft.  I can finally throw in some cushions, sit in it and make airplane noises. (yes, I did do that.)

From Fuselage

July 14th, 2013

This week I've mostly been working on the seats.  I used the tip for using a metal yardstick as a drilling template to make the drilling of the seat angles/hinges more consistent.  My yardstick is riddled at this point since I've used it for 4 different drilling templates.

The first thing was to fabricate the F637B vertical angles for the seat back stiffeners.  These get cut out of a long chunk of 3/4 x 3/4 x .125 (1/8") angle.

From Fuselage

The F637B gets a notch at one end to provide space for the hinge at the bottom. Not having a milling machine, I tried a couple of things - turned out it was easiest to just file it.

From Fuselage

There is a left and right hand version required for each seat, so you have to pay attention not to make two of the same part.

 A piece of piano hinge gets cut and drilled for the bottom (this is what attaches the seat back to the floor pans). There are three separate identical lengths of matching piano hinge riveted to the floor skin. This allows for some fore/aft adjustment for leg room as well as a bit of reclining.

 Since I also drilled several attach points for the rudder pedals, the plane will easily accommodate a variety of pilot sizes, although any adjustments will have to happen on the ground.

 Once the verticals are finished, there are two horizontal angles made from 3/4 x 3/4 x .063, one at the top and one at the bottom.

From Fuselage

Finally all of these parts (including the length of hinge) are match drilled to the seat back, which is a corrugated sheet of aluminum. The corrugations provide additional stiffness.

From Fuselage

Here's the completed assembly after drilling.  The only difference between the left seat and the right seat is the orientation of the hinge at the bottom.  Left side has the hinge set up one way, the right is exactly opposite.  Other than that they are identical.

From Fuselage

A seat back brace F638 is riveted to another piece of piano hinge, which is then attached to the upper back of the seat. This provides sufficient flexibility to accommodate any seat back adjustment, as well as allowing the seat to be folded forward if need be.

From Fuselage

This would probably be very handy in a tip up canopy RV, although with the sliding canopy I'm planning on, I don't see much of a need.  It would also be very easy to take the seat back out if you had something to carry and didn't have a passenger - *that* I could see doing at some point.

Here's the seat clecoed together and installed in the cockpit. In this shot it is in the middle position of the floor attach hinges.

From Fuselage

Here's a side angle shot of the same thing - gives a better idea of how it all fits together. The F638 brace at the top is a tight friction fit into the bulkhead.  The grey angled pieces sticking out of the floor are the seat belt anchors.

From Fuselage

It's amazing how light and strong this is.

 The seat will be a lot more comfortable than it looks. There is a spacer cushion that will be shaped to fit the depression and fit level with the forward seat floor. Then a seat and back cushion will be installed on top of that, so it will end up sitting pretty much like you would in a car. Here's a shot of what an interior looks like all decked out.

July 7th, 2013

Needless to say there has been a lot going on (Becca graduated from High School, Paul & Becky's wedding, electrical problems with Becca's car, repairing/replacing raillings in porch and repairing some rot in one of the columns, new thermostat for Becca's car, working on the Ody for a long road trip, SOAR for Becca at UNCC, Daytona vacation, and repairing some old fence sections and replacing a rotted fence post among other things).

I have been working on the project as time permits, but haven't taken the time to post an update in a while.

Since the last update I've match drilled and installed the aft seat skins, installed the hinges for the seat attachments, fabricated and installed the tunnel support cover, and started working on the crotch strap attach brackets.

June 9th, 2013

Sad week last week. My sister in law's father, John D Hall, USAF retired, passed away May 31st. He was a pilot and Vietnam Veteran with over 750 combat hours in an OV-10 Bronco. He is survived by Linda, his wife of 47 years, 4 brothers and sisters, 4 children, Heidi, John, Jason and Jeff, and 5 grandchildren. We'll miss you John.


 This week I started on the F751 and F652 bulkheads. These are the corrugated vertical panels that cover the back of the baggage compartment. When I was first looking at it and measuring the drawings, it seemed like an 8" radius circle would be about perfect for cutting the upper edge of the F652 bulkhead.

From Fuselage

I often read and look over the plans while eating lunch, and I noticed on one sheet that Van's specified a radius for the cut which I'd overlooked the first time. I'd already laid out the curve from my template, so I made a simple 8 1/2" radius trammel for my sharpie pen to compare them.

From Fuselage

The difference in the curve was so small (especially with the difficulty of getting a decent curve inside the corrugations) that I ended up using the line I'd already drawn. Once I had the curves cut and finished, I clamped & clecoed it into the fuse to make sure it all fit and there was sufficient edge distance all around for the nutplates.

From Fuselage

June 2nd, 2013

We've been doing the annual on our Cherokee the last few weeks so I haven't had much time to work on the  RV.

As I started working on the baggage compartment floors I realized this and the seat pan area were getting ready to be sealed for good.  I know I want to put at least one comm antenna on the belly, and probably two.  That got me to looking at the floors, good spots, etc.  While I was doing that I realized there was some unfinished business, namely the seat belt anchors, bolt/spacer where the rear spar will attach, and I also missed the rivets at the aft end of the outboard seat ribs.  Went ahead and took care of those and final torqued the bolts.

From Fuselage

Lousy shot, but it shows the seat rib that needed riveted and the attach bolt and spacer where the rear wing spar will install later.

From Fuselage

As I was looking over the forward removable seat skins, I noticed I did not install nutplates on the outboard ribs (no idea why I decided to do that unless I misread the plans - I'd already done all the others when prepping the ribs originally).  At any rate, I went ahead and did those.

From Fuselage

After looking around at various RVs and thinking about how I wanted to do the antennas, I still haven't decided on my final plan, but I did decide to make the left baggage floor removable so that if I want to put an antenna in that area I will be able to.  Turned out to be a lot of nutplates to do that, but I feel more comfortable having the option if I decide to go that way.  I put a K1100-08 or a 21051-L08 nutplate at nearly every rivet location.

From Fuselage

The right side F747-R baggage floor skin was installed conventionally.  It takes about 10-15 minutes to do it this way, and I'd guess about 4 hours to do it so it is removable.

From Fuselage

Left F747-L baggage floor after finishing all the nutplates and screwing it down about half way.  Works great and I think I will be glad I did it this way.

From Fuselage

Time to finish the aft baggage compartment wall/skins.  The upper skin needs some work before it can be match drilled and installed.  The top edges need to be radiused first.  After looking at it and doing some measuring I concluded an 8" radius would be perfect.  I poked around and found a 16" pie pan, made a paper template from it and quartered it.  That will be my cutting template once I verify that it looks reasonable.

From Fuselage

The lower baggage compartment wall is more or less finished, just needs to be match drilled to the upper part of the F706 bulkhead.  I'll start that once I get the top skin trimmed to shape.

From Fuselage

May 19th, 2013

Sunday night I had some outstanding work I needed to finish up.  When I joined the two fuselage sections together (tail cone and mid section), I never saw in the plans were they called to rivet the baggage ribs to the F706 bulkhead.  I'm at the point where it's silly not to (not far from fitting the baggage floors and tunnel in fact) so I decided to do that.

For those that haven't done this yet, this would have been *gobs* easier to do while the fuse was still upside down.  As it was I had to go through all kinds of gyrations hanging over the side and trying to rivet these dudes.  It's done, but would have been a lot easier earlier.

Next was to match drill the F709 bulkhead to the rear deck/skin.  I'm going to leave it unriveted for as long as possible since it will be hard to get my hand/arm through the lightening holes if I need to at some point later (pretty confident that will be necessary later on).

Van calls to rivet the F750 baggage sides at this point, then the next line says it's time to install the steps.  One glance at this and you know putting the sides on before the steps is a really bad idea.  Much harder to get to the steps.  So I skipped the sides and started on the steps.

The plans are separate and were written for a -6, although they also talk briefly about the -7 and -9.  Not that different anyway.

From Fuselage

There is a small hole in the side that gets enlarged to accept the step tube.  I drilled this before I bent the skin and riveted it all.  It needs to be enlarged to clear the welds, so I started sneaking up on a good fit - grind/file, test, repeat.

From Fuselage

Here's the weldment.  Pretty rough piece. Needs some cleanup and priming.

From Fuselage

I used tape to make mark my line, then used a coarse grinding wheel to get it to length.

From Fuselage

Here's the inside view.  The outboard rib gets a couple of clearance grooves and the inboard rib gets a hole.  I did both of these before I riveted the center section together.

From Fuselage

Getting pretty close to a good fit.  The lower aft is well off the skin.  I bent it down, but still can't get it tight.  Have to google around/ask to see what other ones look like.  I'm not worried about the strength, but aerodynamically it would be draggy.  If I can't get it tighter I'll have to fair it somehow.

From Fuselage

Once I had it cut to length and it was fitting well I drilled it on the drill press using the pattern in the plans.

From Fuselage

Here's the outboard plate drilled and ready to go.  I trimmed the lower right corner to more closely match the fuselage side.

From Fuselage

Here it is match drilled to the skin and clecoed on.  The second row of rivets from the left needs to align with the F924 bulkhead.

From Fuselage

Once the step was clecoed on it was time to drill the WD657 UHMW block to the rib.  I drilled the holes on the drill press prior to this.

From Fuselage

To drill the rib and step tube to the WD657 block I used an tight fit angle drill attachment on my drill.  Here's the kit I got from Isham's.  It's been really handy.

From Fuselage

Here's the bit and angle drive fitted to the drill.  You can get in a very tight spot with this.

From Fuselage

Here's the block match drilled and bolted to the rib and step tube.

From Fuselage

Once the WD657 block and tube were drilled and bolted, it was time to deburr and prime the steps and rivet them to the skins.

One thing I figured out (don't know if this is good planning on Van's part or just fortuitous circumstance), if you work the holes in the flange correctly, you can get them to fall right on an existing bulkhead rivet, and all the rest will drop between existing rivets. This makes it 1) easy to line up and get started, and 2) works out really well from just a layout point of view. Here's a picture of the rivet I'm talking about.

From Fuselage

Here's the right step riveted into place. Pretty happy with how these came out.

From Fuselage

Once that was done I went ahead and riveted the F750 baggage skins into place.

From Fuselage

Once the side skins are done, the next thing they say to do is rivet the baggage compartment floors into place.

As Dennis says, I need to do some thinking here. As I was clecoing these in, I was looking at what would be inaccessible, and realized I did not have the seat belt brackets in place. I took them off quite some time ago when riveting the center section, and never put them back, thinking there would be a time later when I would do that. It's pretty clear if I don't do them now, I'll have to remove the floor to get them in. Here are the floor skins in place once I put the seat belt brackets in and torqued them.

From Fuselage

I also plan to put the transponder antenna on the bottom of the fuse, and probably two comm antennas. I need to either put in an access plate, make the whole floor removable, or put them in and seal them up (the last one isn't really a serious consideration). For now I'm going to do a lot of noodling/planning/idea stealing, and not actually rivet the floors in since they are easily (and as far as I can tell painlessly) done a bit later.

I also have a couple of rivets on the outboard ribs that aren't done, as well as the spacer block that goes in the rear spar slot and gets bolted in.  I'll do those next.