Chris’ Pitts S1-SS Project

I haven’t posted much recently, but that doesn’t mean that I haven’t been building. I’ve kinda hit a stopping point on the left lower wing while waiting for some materials from Aircraft Spruce, so I have decided to start working on the right lower wing. As far as the left lower wing goes, I need to drill holes for the Drag anti-drag wires, decide what i’m going to do as far as the wing tip, and bond the plywood leading edge. There are also a few small miscellaneous things to do as well, . It has taken me about a month and a half to get to this point and my goal is to have this second wing done by the end of January, which means 2 weeks:) We’ll see.

So the last few days have been spent prepping the ribs for the right lower wing and bonding them on the spar. Today was spent cutting out the ply doublers for the aileron bellcrank and idler, the ply doublers at the wing attach points, and the I-strut doublers.

I am running out of room in my one car garage so I had to find a place to store the wing that is already assembled. I decided to hang it on my bedroom wall.

I received the Drag / Anti-Drag Wire Blocks from Steen Aero yesterday so I plan on bonding these this week.

EDIT: Drag / Anti-Drag wire blocks were bonded today. 01/05/2009

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In order to bend the aileron cove, I needed to steam the 1\16th in. ply. I did this by placing the ply in the dishwasher. I got this idea from the biplane forum and it worked great. I grabbed a couple of 2×4’s and clamped them to the table with about a 3″ gap between them. Once the ply had been steamed, i placed it over the 2×4’s and then placed a round PVC pipe on top of the ply, and over the gap between the 2×4’s and then put some clamping pressure on the PVC pipe. We’ll see how this turns out. I have a feeling i will need a smaller PVC pipe.

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I also mounted the pitot\static tube today.

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Last night was spent mounting the bellcrak and idler.

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The last few days have been spent bonding the aileron idler and bellcrank ply doublers to the spars. I also bonded on the trailing edge and started work on the wing walk. Underneath the wing walk, i made some cross braces out of 1″ x .3″ spruce. I am making the wing walk out of two pieces of 1\16 ply. I want the wing walk to be flush with the leading edge and the leading edge is 1\16th ply so i made the braces 1\16 lower than the top of the airfoil, bonded on one ply flush with the top of the airfoil and another ply over the top of that whole structure which should come out flush with the leading edge ply.

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Last night I had an hour of free time so I decided to go out to the garage and do a little work on the wing. I cut out the 1/2″ x 1/2″ spruce stock for the triangular corner blocks on the ribs and was only able to bond about 10 on. I also, spent some time doing misc. cleanup of the glue joints.

I didn’t really accomplish much this weekend but I managed to bond the root spar doublers and the I-strut ply doublers.

I decided last night that I wanted to change all the gussets that butt up to the spar from the semi-circle gusset to one continuous vertical gusset. This will allow me to run a triangular corner block from top to bottom of the spar which should give it more strength.

So i spent about an hour grinding off all the gussets and a couple more hours cutting out the new ones and bonding them on.

Today was spent cleaning up the ribs again, and squaring up the wing, again!

Once I had the wing sqaured up, I spent the rest of the afternoon bonding the ribs to the spar.
In order to save myself alot of sanding, I placed ducktape on any surface that was going to get a secondary bond, such as the spar and gusset area where the triangular corner blocks are going.
Once the glue was applied and the rib slid into place, I removed the tape before the T-88 epoxy set.
Finally, I did one last check to make sure all the ribs were square before closing up shop for the night.

Spent a few hours today trying to get the wing spars square and level so i can start glueing the ribs on. I made a few wood jigs that would allow me to clamp the spars to the saw horses, and also move them up or down to get them level. Wasn’t alot of work, just time consuming to get everything nice and square.
I also cut out the spar doublers where the I-Strut attaches, and also the doublers at the root of the spar.

So today was a big day. I spent the day cutting out the lower wing spars. This took quite a bit of time as I didn’t want to screw them up.

When that was done, I spent some time cleaning up the ribs so they would slide onto the spars nice and snug. I screwed up the butt rib when i was fitting it to the spars and accidentally broke it. Guess I gotta make a new one.

After all the ribs fit nice, I took a break and ran to Home Depot to buy some wood saw horses to use for jigging the wing. When i got home, I layed out the wing on the floor and bondoed the saw horses in place so they wouldn’t move.
I then measured and layed out the placement of the ribs on the spars.

Then it was time to slide all the ribs onto the spar for the first time. Kinda exciting because it’s starting to look like a wing.