Archive for November, 2010

Preparing to Close the Left Tank – 1.0 hr

November 29, 2010 Leave a comment

Monday Nov 29, 2010

Well the last week saw no progress on the wings since it was Thanksgiving and we were out of town. So tonight was the first time back in the shop since last Tuesday. It is about time to close up the left tank by installing the baffle and that is a major milestone so tonight I began final preparations.

That includes bending the fuel vent line to the high point of the tank as seen here.

It also includes buffing up the surfaces of the baffle which will be sealed including the edges of the flanges and along each of the rib lines as you can see here.

I also inspected all of the rib seals to make sure there are no obvious leak points and all rivets are covered in sealant. It looks good. I hope there are no leaks but I won’t know until I seal up the baffle and access cover and perform a leak check. I’m praying for a leak-free tank.

I also ground down the nozzle of an old blind rivet tool I had so be able to pull the blind rivets on the T-712 Z-brackets. I’ll get a picture of that tomorrow.

Categories: Fuel Tanks, Wings

Tank Rib Riveting Part 4 – 6 hrs

November 23, 2010 Leave a comment

Tuesday Nov 23, 2010

Hooray, I finished riveting the ribs into the left tank skin today. I started with the center rib with the help of Denise, then I installed the inboard rib. For the record, here were the inboard rib steps:

1.  Insert the fuel tank vent line through all the outboard ribs (snap bushings installed).

2.  Clean mating surfaces of the inboard rib, skins, T-405 and T-410 with MEK.

3.  Apply sealant to the flanges and cleco the rib into the skin.

4. Rivet the rib to the skin starting at the leading edge and working toward the trailing edge using the pneumatic squeezer.

5. Apply a fillet around the interior and exterior edges and make a cap of sealant over each rivet.

6. Apply a layer of sealant to the mating surfaces of the T-410 and T-405 and cleco the parts to the tank rib.

7.  Set the rivets using a cup set with snap socs.

8.  Apply a fillet around the interior and exterior edges of T410 and T-405 and make a cap of sealant over each rivet inside and outside.

9.  Clean the flop tube fitting with MEK. Apply sealant and install the flop tube fitting and torque to 115 in-lbs.

10. Apply a fillet of sealant around the AN fitting.

11.  Clean the vent line fitting with MEK. Apply sealant and install the vent line fitting and torque to 50-65 in-lbs.

12.  Mate the vent line nut and torque to 50 in-lbs.

13.  Apply a fillet of sealant around the vent line fitting and around the vent line nut to seal the threads.

Here is the end result. No clecos!

In this photo you can see the inboard rib and the installed flop tube.

On the inside you can see the diagonal anti-hangup bracket and the vent line mated to the fitting. This tank is just about ready to be closed up by the aft baffle.

Categories: Fuel Tanks, Wings

Tank Rib Riveting Part 3 – 6.5 hrs

November 22, 2010 Leave a comment

Monday Nov 22, 2010

Three more ribs riveted into the left tank today. I started working early this morning on the outboard rib because I could squeeze all those rivets without any help. Then I completed two more of the inner ribs with the help of Denise. I found that if she drove the rivet gun while I bucked on the first six to eight rivets on each side (starting at the leading edge) I could easily finish the rest solo. That tied her up less so she could get other things done.

Here is a shot of the outboard rib. I used electrical tape to mask off the area where the doubler to the leading edge slides in.

Here is the current status of the left tank. Notice that only two ribs have clecos at this point. The rest are fully riveted. Slowly but surely.

Categories: Fuel Tanks, Wings

Tank Rib Riveting Part 2 – 1 hr

November 21, 2010 Leave a comment

Sunday Nov 21, 2010

Not a lot of time to build today. I just had time to rivet the T410 reinforcement plate to the left tank outboard rib. The instructions say to do this after the rib is riveted to the skin but it is much more accessible before the rib is installed and I don’ t see anything that will be negatively affected if I do this now. I hope that turns out to be true.

I cleaned the areas of the parts that were to be bonded first. Then mixed up about 15 grams of sealant and buttered it onto the surface of the reinforcement plate, mated the parts and cleco’d every other hole. Then I squeezed the rivets. I cleaned up the excess sealant and added a bit over each rivet head.

Here is the reinforcement plate after riveting and sealing rivet heads.

Here is the inside of the rib. The seventh blob is an extra tooling hole in the rib that must get sealed up in this process.

Categories: Fuel Tanks, Wings

Started Riveting Tank Ribs – 4 hrs

November 20, 2010 Leave a comment

Saturday Nov 20, 2010

This morning I started riveting ribs into the left tank skin with the help of my wife Denise. There are seven ribs on each tank and it really helps to have one person driving the rivet gun and one bucking rivets on the inner five ribs. The two end ribs can be squeezed so I can do that solo.

The process went better than I had feared. I was a little anxious about this step because of the ProSeal mess and the fact that reworking rivets in ProSeal is kind of a mess. We managed to keep the ProSeal contained and only had to drill out one rivet. As recommended in the instructions I prepared all the tools and parts before starting. I also cut out about 50 2×2 inch squares of paper towel to use to clean up ProSeal along the way. I mixed 33 grams of sealant (30 grams white + 3 grams black) for each rib and that was enough to butter up the flange, dab a dot on each rivet dimple, and fillet around the flanges after setting all the rivets. I also had enough to make a seal cap over the rivets on one of the two ribs installed today. Here is a view of the first rib installed. The fillet has been made around the perimeter of the flange but there are no caps on the rivet heads yet.

Here is the other side of the rib with the fillet installed. I used a syringe like a caulk gun to lay down the fillet.

Here is the second rib installed with the fillet and each rivet head sealed.

That’s two down and five more ribs to go on this tank. Then there is the other tank to do also. Looking forward to being done with ProSeal.

Categories: Fuel Tanks, Wings

Rivet Fuel Sender Reinforcement Rings – 1.5 hrs

November 14, 2010 Leave a comment

Sunday Nov 14, 2010

The business for today was to rivet the reinforcement rings and nut plates to the tank baffles. ProSeal is probably not necessary for these parts because the fuel level sender will be installed with ProSeal later but I decided to seal them anyway. Duh!

The process was fairly straightforward with no surprises. I scuffed with scotch-brite all the surfaces, cleaned with MEK, etc, etc. The photo below shows one of the two with rivets set but before I applied ProSeal over the nut plate rivets.

And here is one of the two after sealing it all up with ProSeal. I did not have any clean syringes so its a bit messier than my earlier attempts. The other reinforcement ring looks much the same.

That’s all I completed on the wings today because I had a broken sprinkler pipe that I spent a good part of the afternoon fixing while I had sunlight. Life sometimes gets in the way of building.

Categories: Fuel Tanks, Wings

Misc Fuel Tank Riveting – 2.5 hrs

November 13, 2010 Leave a comment

Saturday Nov 13, 2010

I passed my written test for my private pilot certificate today with a score of 95. I guess I could have done better. Now I just have to complete that check ride and I’ll be legal.

On the building front, I riveted a few miscellaneous items on the left tank ribs in preparation for starting to rivet the ribs into the skin. First was the flop tube anti-hangup bracket on the access cover. The two z-brackets need to be sealed or they will leak of course. Here you can see the z-brackets riveted on first with ProSeal.

Then the top strip was riveted on. No sealant required here.

Next was the tooling hole on the outboard rib. I ordered a few AN470AD6 rivets from Vans for this purpose. They were too long so I cut one down to about 3/16 inch. After scuffing and cleaning everything I applied sealant to the rib around the hole and inserted the rivet. Since my squeezer won’t handle an AD6 rivet I put the factory head on my anvil and wacked the shop head a few times with a hammer to set the rivet. It turned out better than I expected. Then I applied the usual fillets and caps to seal it up good. Here is the factory head side.

Here is the shop head side.

Then I riveted the flop tube anti-rotation bracket to the inboard rib. This was straightforward and I was able to squeeze both rivets.

Categories: Fuel Tanks, Wings