Rudder Pedals

Quick update for today: my reinforced pedals are now painted and ready to be reinstalled! I have read that some S1 pilots experienced failures of their brake pedals. A thread on biplane forum here talks about this problem. I haven't found mine broken but since I had to make welds on the fuselage, I took the opportunity to add small gussets out of 0.050" thick 4130 steel before they do! Also decided to change the colour from black to light gray to ease up inspection for cracks. Here is how they use to look before I removed them (the weak parts are circled):

Here's how they look now with the reinforcements shown by the arrows:

Thanks to my friends Mark and Scott for the nice welds and paint!

Lower wing attachment #2

Just a quick update today: I cutted off the bushing to final dimensions. It's now ready for primer and paint!

PS: yes I will use a longer bolt!

Lower wing attachment

Over the last month, I went to AirVenture for the first time and I moved right after my return so I had no time left for the Pitts but now I'm back into it!

Last couple of days I worked on an issue my friend François (who won the Canadian Nationals in intermediate last week!) snagged on my airframe: an elongated hole on one of the lower wing attachment point on the fuselage:

 

 

On this view, the hole elongation is clearly visible (about 1/16th play!):

At the begining I really didn't know what to do, but I called my other friend, Mark the welder and he told me it was possible to weld a new bushing. First I fitted my LH lower wing with the great help of Marc-Antoine (my partner on the Citabria) in order to locate the required position of the bolt. Then I had to make myself a little jig with a piece of aluminium to ensure I mark where I wanted the bolt to be aligned:

Then I grinded off the old bushing using my dremel with a cutting disc:

Next step was to enlarge the hole to the OD of the bushing and remove the paint on the forward lug of the bracket:

Then I called Mark and asked him to come over and weld the new bushing in place. We placed fiberglass cloth as well as wet cloth to protect the fabric from the heat:

Then Mark used his magic and welded the new bushing in place:

Next step will be to grind off the bushing flush on the aft end and a little shorter on the forward end. Then I'll have to prime and paint... Stay tuned!

Welding Part II and return to base

Yes you've read the title right! Big milestone reached in the repair process last week-end: the welding of the fuselage is complete!

The following was completed since the "welding part 1" post:

• Finished the welding of the bottom tubes
• Welded the side diagonals
• Welded the sidelugs

The team in  Aerosoudage did an excellent job. Here is a picture of the RH lower longeron with its sidelug in place:

View looking down showing the bottom tubes and the bushings:

This time I rented a truck to bring the fuselage back to the hangar:

...and finally, the fuselage back in the hangar!

 

 

Next step is the paint job. Stay tuned!

Sidelugs

One of the last steps of the welding process is to weld the sidelugs on the bottom longerons. I've contacted many local sheet metal shops to see if they could bend the 0.025" thick 4130 sheet I had. The bends required are close to each other and shops were generally reluctant in doing the job. I therefore decided to make them myself.

My initial design looked like this:

 

The original sidelugs did not include the step as you can see above. I needed to add this step in order to accomodate the new thickness change of the lower longerons. However, making this out of one piece with the few tools I have was a little complex so I decided to split it into two parts:

 

 

Had to make a holding tool to make sure that the metal was securely held in place. I used two pieces of 3/8 thick mild steel with a little radius on the corner of one of them. Here is what my bending setup looked like:

 

 

 

 

I used screws going through both plates to provide additional clamping force near the edges. The bar you see on the right is a piece of 1/2" thick steel I used to hammer the base of the protruding part of the sheet metal. It took a lot of effort to bend this only with a hammer. After two nights of work, I had the four pieces bent the way I wanted:

 

 

 

The last step before welding to the fuse is to trim the excess material used to clamp them in place. I left this job to my welder since he is going to determine their final location and might need extra length.

 

Next post will be about the final welding and if everything goes well, about the ferry back to my home airport!

Welding Part I

It's been a long time since my last post; busy at work and many other projects going on. Here's a quick update to describe the great progress made on the welds!

Lower longeron external sleeves and gear bolt bushings were welded in place as well as the rudder pedal hinge bushings:

I took this opportunity to shift my pedals 5/16'' forward since I'm 6'1'' tall and my knees were a little close to my instrument panel with my previous setup.

Next step is to weld the brake cylinder attachment tubes and bushings as well as the lateral diagonals. Last step will be to weld the footrest brackets and lateral panel nutplate lugs.

I take the opportunity the congratulate my acro mates Luc Martineau (Sportsman, Pitts S-2C) and François Marquis (Intermediate, Christen Eagle) who got to the Wildwood Acroblast contest this week-end and both won first place of their category! Great job guys!! Here's a little picture of us 3 almost 2 years ago:

Last steps of dismantling

Over the last week, Mark made great progress in removing the excess welding maetrial from the old repair. He pretty much removed everything that needed to be removed except the portion of the flat plates still welded to the bottom longerons.

 

I wanted to use these plates one last time before removing them and here is why. As I need to oversize the gear attachment bolts (AN5 to AN6 size), I need to get rid of the old bushings and replace them with larger ones. I decided to progressively drill them out until reaching the OD of the new bushings. In order to achieve that with reasonable precision, we decided to fix a mag drill on a steel beam sitting on the bottom longerons while the fuse was mounted upside down:

 

As you can see, having the old flat plates still welded to the longerons was a good reference to clamp the steel beam on the fuse. Big thanks to friendly Claude from whom I could borrow the mag drill.

 

While Mark was working on removing the old welding last week, I decided to take the opportunity to make a small modification to my landing gear. I wanted to do this for a long time and since everything is teared down, it is much easier to do it now: rotate my brake calipers aft. My original setup was with the calipers mounted downwards and I didn't like much the idea of scraping the caliper on the ground if I ever have a flat tire or tire burst.

After a few tests playing with the different components, I found the caliper position that I think was a good compromise; it needed a small adjustment of the nutplate attachment lug and a bit of trimming on my wheelpants.

First I washed the wheel hub and brake parts with varsol to have clean parts to work with:

 

Then, I slightly trimmed the nutplate lug, and with the use of a cardboard template and my Dremel with a cutting wheel, I trimmed of the piece needed on the wheelpant:

And here is the almost-final result:

 

I'm going to have a little extra trimming to do to clear the fitting on the top, but I preferred to have the final fitting in hand before doing that.

The 4130 steel tubes and plates are in transit right now. With chance, I will receive it this week and start trimming the first tubes this week-end!