Thursday, January 7, 2016

Section: 18
Hours: 4

I've been procrastinating the last couple days.  I can't say I've been enjoying working with the ProSeal and it's been really cold in the garage. I decided to spend some quality time outside away from noxious chemical smells.
Fresh pow- whoopee!!!

Today I got back to it. I riveted in 2 1/2 ribs to the left tank. I had been debating using the fay sealing vs wet riveting method and after riveting the stiffeners I decided to try wet riveting. The official construction manual specifies wet riveting so what could go wrong?

I decided to mix up a fresh batch for each rib so I would have maximum working time before the ProSeal starts getting stiff. ProSeal wets out and squeezes down much better within the first 30 - 40 minutes after mixing. It takes about 20 minutes to mix up a batch and butter a rib. It then takes another 10 - 15 minutes to insert the rib and get the holes lined up and clecoed. At this point in the cure, the clecos squeeze out some of the ProSeal, but not as much as the riveting does. If I was fay sealing, I would stop after clecoing and rivet tomorrow after the ProSeal has set up a little. It seems to me that that would leave too thick a layer of ProSeal between the rib and the skin and it wouldn't necessarily squeeze out any air bubbles or voids. If you shoot the rivets immediately, a significant amount of additional ProSeal gets squeezed out leaving a nice bead around both sides of the rib.

Today it took me about 45 minutes to insert rivets and set them. In the end, each rib was taking 1.5 to 2 hours. I think I will be able to speed the process up as I gain more experience. I was glad that I already had experience building the outboard leading edges - I learned how to set the tricky rivets in the nose area on a dry assembly. Today I didn't have to drill out any rivets. What a mess that would be...

Here's a row of rivets after wet riveting. You can tell each head is backed with ProSeal because of the excess that squeezes out around each head.

Here is what the rivets look like after wiping off the excess ProSeal with a slightly dampened with acetone paper towel.

Here's the typical squeeze out immediately after riveting.

After riveting, I touch up the edge with ProSeal and make sure the tabs with rivets in the nose area are adequately sealed up.

The end rib must be sealed with a 3/8" radius fillet of ProSeal. A popsicle stick worked well for working in the additional ProSeal to form the fillet.

Here's the outside of the tip rib after dabbing sealant on the rivet heads.

I was able to finish 2 1/2 ribs today. Now that I know what I'm doing, hopefully the rest of the ribs will go faster.

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