Today, I didn't have to work as it was my Friday off>>  WooHoo!!!  It looked like a beautiful day outside, so with my usual routine, I came down and checked the weather for today and was shocked to see that the Omaha area had set a new record low temperature.  You know, I just got done installing an air conditioner in the garage because this area is usually so hot and for the last week and a half, the temps have been fabulous.  We are even seeing record low temperatures.

Today's weather was awesome...  It got into the mid 70's, sunny with winds <5 mph.  I just couldn't resist getting the Goldwing out and putting some miles on today.  I cleaned up the garage as it looked like a tornado came through there.  Sealing fuel tanks has taken its tole on my organizational efforts.  By the time I got that all straightened up, Tami came home from work so we took off for a motorcycle ride.  We ended up in Shenandoah Iowa.  We swung by the municipal airport and watched a student practice some touch and go's in the beautiful weather.  I was torn, I wanted to be flying and riding...  To many hobbies, not enough good weather or time.  Anyway, I took my tank sealant helper out for dinner for all of her support so far and so I can guilt her into helping me seal the baffle in place later this weekend.

I did manage to get a couple of odds and ends done on the tank.  I am more or less taking my time making sure that I am not forgetting anything and looking over all my tank sealant "BLOBS" making sure I have adequate coverage.  I don't want any leaks after I seal the baffle plate in place.  I noticed that after I had sealed the rib with the flap door, the door rubbed up against the tank sealant fillet.  I didn't want the door to dig a hole in the tank sealant over time, so I removed the door and took it over to the bench grinder to reshape the flap door on the forward edge.  A couple of seconds on the bench grinder, viola...  I re-installed the flap door and it no longer rubs on the tank sealant fillet (and it still covers the tooling hole).  WooHoo...  EASY FIX!!

To hold the trap door hinge pin in place, I just dabbed some tank sealant over the bent hinge pin.  I made sure that the amount of tank sealant I put on here would not interfere with the rear baffle, when installed.

Next I slopped some solder on the BNC connector for the capacitance fuel sender.  Okay....  I am an ELECTRICIAN and we live by the following creed when it comes to soldering: "The Bigger The Blob, The Better The Job".  Therefore, this is a great job.  No really, my solder work would not impress any electronics guru that has a lot of (or even a little) soldering expertise.  I gave the connection a good tug to ensure it was secure (you don't want a cold solder joint) and then measured the resistance between the center of the BNC connector and the capacitance plate.  I got a value of less than 0.2 ohms.  The test leads alone measure 0.1 ohms so my reading is good.  I then measured from the center of the BNC connector to the rib (to see if I had a ground) and the multimeter indicated over range (OL) which is a high resistance and a good reading.

I covered the back side of the BNC connector with ample tank sealant and I also covered the wire with tank sealant back a couple of inches as the tank sealant also provides some limited strain relief for the wire.  Additionally, the tank sealant covering the wire will prevent fuel from "wicking" up the wire into the BNC connection.  The BNC is a potential source of leakage as it can only be sealed on one side.  Most everything on the tank can be sealed on both sides thereby having more than one sealant boundary.

While doing some research on installing a fuel vapor return line, I came across a short article in a book I am borrowing' "21 years of the RVator" and it talks about the flop tube o-ring coming off the brass pickup.  Van's recommends to proseal this o-ring in place to prevent it falling off after the tank is closed up.

You know, I wished that Van's would just put this information in their instructions or just sell the flop tube with this o-ring already sealed in place.  But then again, they pretty much lack any useful information regarding the flop tube installation so why add this nugget of information either?

As with Van's instructions in the 21 years of the RVator, I put some tank sealant under the o-ring on the flop tube brass pick-up to hold it in place.

I broke down and purchased a Fluke 177 DMM.  Some type of multimeter or test equipment should be used to check the capacitance sender installation prior to closing up the tank.  This would also apply to the resistance (float) sender too.  I figure that this meter will come in handy throughout the project's electrical installations.

Today, I set out to get more tank sealing done so that I could knock out sealing tank ribs next week.  I didn't think today's sealing efforts would take but a couple of hours and then I could get some work around the house done.  WRONG!!!  Tami and I riveted the leading edge together in about 2 hours.  Tank sealing is turning out to take me a WHOLE LOT of time.  Over 20 hrs of riveting and sealing and I haven't started on the ribs yet.

Below, I riveted in the anti-hangup bracket for the root rib inspection hole.  I fully encapsulated the bracket and rivets.  Most builders do not do any sealing on this inspection hole as it is sealed by either the inspection cover gasket (if you use it) or the inspection cover plate is sealed with tank sealant to the outside of the root rib.  I have opted to use some after market sealed (floating) plate nuts.  I am hoping that sealing this reinforcement ring and other hardware, that I am able to use the gasket that is supplied with the kit.  If I need access to the tank or the gasket ever needs changing, no problem as my leakage paths here at the root rib are only through the "Big Hole" and not around every plate nut rivet and plate nut screw....

The next component sealed was the drain flange.  The drain flange was machine countersunk at the factory and the factory rivet heads are almost perfectly flush.  I frosted up the back side of the drain flange and slapped it on the skin and threw a couple of cleco's to hold it in place.  I was able to squeeze all of these rivets with the pneumatic squeezer.

Just another angle of the drain flange.

This is the back side of the drain flange.  As with all of my sealing to date, I fully encapsulate my rivet shop heads.  I tried to keep the skin between the rivets clear of tank sealant.  I didn't want any condensation in the tank from being impeded in its flow toward this drain flange.

This is a picture of my outboard rib tooling hole.  I cut a triangular shaped piece of aluminum and riveted it over the tooling hole.  The only trouble with this I had is that I didn't have any solid rivets short enough.  I did have some CherryMax universal blind rivets that were short enough.  The CherryMax universal rivet had a larger shop end.  The CherryMax rivet is really a pretty sophisticated rivet when you read through Textron's technical bulletin.  Link To:  CherryMax Rivets Info

I just placed copious amounts of tank sealant over everything.  This sucka is not going to leak.

This is the outboard side of the rib.  Again, plenty of tank sealant over the hole and the factory heads of the CherryMax universal rivet.

The last three sealing operations were not to bad.  Okay, now it is on to the problem child of today's efforts.  The fuel filler flange....  What a pain in the arse.  I started by clecoing the ribs in on both sides of the filler flange to hole the tank skin in its basic arc.  Then with all tank sealing efforts, I frosted up the filler flange to skin surface and cleco'd in place.  I got Tami to help me with this as I was not going to be able to reach every rivet with the pneumatic squeezer so I decided to buck these rivets.  They were all fairly straight forward with the exception of one rivet (read on).

After Tami and I got about 3/4 of the rivets set, we removed the ribs to gain access to the remaining rivets, including the difficult one...

Okay, can you guess which rivet on the filler flange is the problem child???  Hint:  It holds the vent line clip (T-714).  How am I going to set that rivet?

• Grind down end of bucking bar to get in between the filler flange and the clip.  NOPE>>>  Didn't work.  The end of the bucking bar that was flattened with the grinder does not allow enough surface area to properly form the shop head.  DRILL OUT RIVET start over.

• Use pneumatic squeezer.  NOPE>>>  Yokes are not long enough.
• Back rivet against bench back rivet plate.  NOPE>>>  Didn't work.  Factory rivet head set high, couldn't get skin to set up against back rivet plate.  DRILL OUT RIVET start over.
• Hold bucking bar on factory head and form shop head with rivet hammer and back rivet attachment.  YEP, GETTING CLOSE.  However, flattened out rivet shop head.  *&$%*%*$#@!*.   DRILL OUT RIVET AGAIN, Inspect T-714 clip find out clip mounting point is distorted....  Fabricate new vent line clip and start over.

On the 4th try, I did get a properly set rivet.  However, I will do this rivet slightly different on the next tank.

As you can sort of see in the picture, the factory head is not completely flush on all sides.  This is in part due to the fact that this is where the skin has the most curvature.

One the next tank here is what I am going to do for this troublesome rivet:

• Use the bucking bar on the factory head side.
• Use the rivet hammer back rivet attachment to get in between the filler flange and the vent line clip.
• Use a short burst (2-3 hammers at a lower pressure (approx 35 psi with my Sioux 2x rivet hammer).
• Rotate (rock) the bucking bar a couple of degrees forward to attempt to keep the factory head flush with the curvature of the skin.
• Use a short burst (2-3 more hammers).
• Check shop head for proper dimensions.

After all of this, I was sticking to everything.  I spent the rest of the night cleaning up.  WooHoo....  Am I done with this tank yet?

Only specialized words can be used to describe construction progress on this Memorial Day Weekend.  Fargin-Nuget!!!!!  I didn't get diddly squat done on the plane this weekend.  Last week I was planning on having a "tank marathon" this weekend.  THAT DIDN'T HAPPEN!!!

Instead, I got caught up working on things around the house.  My "To-Do's" have been growing and I only got a couple of them done this weekend.  I could spend the rest of the summer on them and probably not get done.
This weekend's accomplishments included:

• Overhauling the gas grill.  Believe it or not, this took over 4 hours to clean and replace everything.  If you think tank sealant is messy....  It is nothing when compared to the muck I found in the grill that I haven't cleaned for probably 4 years.  YUK!!!!
• Mounted a wall mount for the TV.  Now I have room for my satellite receiver and a DVD player in the garage.  200 satellite channels and I still have a hard time finding something decent to watch.
• The BIG item for the weekend was wiring and mounting my new 24,000 BTU, ductless, split-type heat pump for the garage.  LINK TO:  Garage Heat Pump
• Minor work on the right wing tank.

Tami and I dimpled the tank skin.  The thing to be careful with here is not to dimple the fuel sampling rivet holes as the fuel sampling flange is countersunk by Van's.  The other holes you don't want to dimple on the skin is the rivet holes for that will attach the tank baffle.  The tank skin is to be countersunk  (have not done that yet).   After Tami and I got done with the skins, I dimpled the tank ribs.  Just another exercise in using the C-frame dimpler and the pneumatic squeezer.  Sorry, no pictures.

I am still fabricating components for this friggin' fuel tank.  I started working on the fuel trap door that blocks off a large hole in the same compartment as the flop tube.  The idea here is that the trap door flops down to block the hole and prevent a mass exodus of fuel adjacent to the flop tube during aerobatic maneuvers.  Okay, if you say so Vans.  I don't think that it would be a good idea to starve engine during aerobatic maneuvers.  The plane would only take you to the scene of the crash.  That could make for a really bad day.

I used some AN257-P3 piano hinge and cut it to 2.5" long.  It later gets cut to 1.75" so that you can bend up the tab to act as a stop.  I used some scrap 0.025" aluminum to fabricate the trap door.

Additionally, I cut a curved notch along the aft side of the trap door so that it did not block the notch in the lower portion of the rib.  Van's states that this notch in the rib is to allow water to migrate and pool at the bottom of the tank near the drain valve.  I wanted to make sure the trap door didn't hinder that water migration.

I riveted the trap door to the hinge with AN426AD3-3.5 rivets.  For the top side of the hinge to rib web, I used AN470AD4-4 rivets.  I didn't want to mess with countersinking the hinge, so I just used universal rivets.  Van's instructions on the print do not specify the rivets to use.  Those rivets ought to hold that friggin' trap door on....

Finally, I bent the hinge pin 90 degrees on the aft side of the trap door.  When the fuel tank is fully assembled, the tank baffle plate will be riveted to the aft rib flange and prevent the hinge pin from coming out.  If that hinge pin comes out, I am going to have serious other problems to deal with...

One long weekend, one piddly little trap door fabricated.  I gotta pick up the pace here.  Two other builders whose progress I follow regularly (David R. and Dave P.) smoked me this weekend on progress.  Good job guys.  I will get out of my slump soon.  I must have this subconscious phobia with working on the tank....