Curtiss Jenny Restoration

Welcome! We hope you enjoy following the restoration process of a 1918 Curtiss JN4D Jenny. Once completed, the aeroplane will be flown and displayed at the Candler Field Museum in Williamson GA (30 miles south of Atlanta). You can contact me below by clicking on "VIEW MY PROFILE"

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Location: Peachtree City, Georgia, United States

Sunday, February 27, 2011

After much thinking, and some cajoling from Brian, we decided to make the center section rigging jig after all. It is possible to rig the center section without it, but the more we tried, the thought of having the center section securely in place while we built the wires became appealing.

There is a Curtiss drawing of the jig, mostly made of U channel material and angle stock. We did not make the jig exactly the same way, but used the dimensions (16 in stagger, etc) and made our own jig out of angle aluminum.

Ron and I drew the dimensions on the table and started measuring aluminum.

Here is the general layout.

The jig is designed to be disassembles after we are done. That way I can ship it to future Jenny restorers without much trouble.

Here is the jig in place.

The wing attach points are here. There are fittings on both sides of the jig. One set for the right side. One set for the left side. One jig. Two uses.

Now that the jig was completed, the cross wires were built with some 5/32 in. 1x 19 non-flexible cable.

One of many...

The cross wires in place.

Here is where they attach on the fuselage. Sorry for the blurry picture.

We made the rear center section-to-fuselage wires too.

These two wires attach on the lower longeron behind the rear seat and run through the cockpit.

Here is another shot.

A good couple of days work. Enjoy!


Thursday, February 17, 2011

Wire fittings

The king post bracing wire fittings were brazed together this morning.

Then they were drilled and countersunk.

And finally, a complete set - originals in black. reproductions in primer.



Wednesday, February 16, 2011

center section

Ah, the center we go again.

As I mentioned earlier, when we put the cabane struts in their sockets, we got a 14 inch stagger between the upper and lower wings rather than the 16 inch stagger we needed. So, I knew the bottom angle on the cabane struts had to be changed.

This was frustrating because the cabane struts were perfectly made exactly to the Curtiss drawings.

So, we had to change the angle of the struts. Easy, right?

Well, not really. Not only was the angle wrong, but the distance between the center section and the lower wing was off, too. There is supposed to be 61 1/4 inches between them. We had 60 3/4 in. I was not very happy. The frustration level was very high.

Sometimes sleeping on a problem is the best thing to do.

With a clear head, a solution was worked out. We cut the back of the struts to get the proper angle for the 16 in stagger. Then we added material to the bottom of the struts to get the proper height.

Here you can see the new steeper angle with the laminated spruce pieces.

Now we have a 16 inches of stagger and 61 1/4 inches between wings. Next step is to drill the holes, varnish and copper.

I took some time today to lay out all the wing hardware.

These are original forgings. The wing struts attach here. One plate needs to have a tab cut off and put on the other side but otherwise, we have a complete set.

We were missing one kingpost wing wire attach fitting, so using the original as a pattern, another was cut out of sheet steel. It will be brazed together, the oblong hole cut and countersunk next.

I was also missing one upper wing flying wire fitting.

The original on the top was also used as a pattern.

Here's a shot of the project so far. We're getting there!

John Gaertner made some of the aileron wire pulleys for us. They are two halves brazed together.

Here is a picture of the original one on the top left and the reproductions.

John sent me these pictures of Lt. Campbell and his Jenny right after he set the record for the most continuous number of loops back in 1918. What struck me was the straight exhaust stacks on the Hisso! Check that out.

Here's another picture of an OX-5 Jenny.

More soon. enjoy


Thursday, February 10, 2011

Oil Tank and Bushings

It was an eclectic day today.

I went to the hangar early after dropping the kids off at school. I only had a few hours before our youngest son needed to be picked up, so I grabbed the sheet of .050 5052H sheet aluminum and began cutting out the oil tank. The pneumatic shears are worth their weight in gold!

After staring at the void on the firewall, I decided on the tank dimensions. Then I added 1/2 in. on all the sides for bending and welding.

I used this picture of a Hisso Jenny to determine the shape, size and location of the oil tank. You can see the rectangular tank right below the rear of the engine. Looks like a little suitcase.

The corners were cut out for bending.

So ended the morning. I picked Brighton up at school, ate lunch and then the other kids came home. Homework, dinner, 745PM I was back at the shop.

Richard Epton's box brake made the oil tank flanges perfectly.

Here is the oil tank going together. I have never welded aluminum before (I want to learn someday), nor do I own a TIG welder (I want one of them one day, too), so I will take the tank to a local welder. I have been debating whether the 1/2 in. flanges are too much material for welding. Maybe I need to cut them down to 1/4 in.? We will see what the welder says.

This is the basic tank. The inlet/outlet/drain bosses need to be welded on too.

While I was at Richard's shop, I made the bushing for the control stick pivot. For some reason, there was slop in this piece. The only way to fix it was to bush it.

So, a 5/16 in. drill bit was used for the ID.

And then the outside was cut down to 21/32 in.

It is a thin bushing, but it takes the slop out of the elevator control. The bushing will be cut to fit the pivot tomorrow.

The aileron pulleys needed bushings too. I had one original pulley which had a bigger hole than the AN3 bolt that helds the pulley onto the seat rail. Once again, a bushing takes care of that.

Now you see how it fits. This bushing will also be cut to size later.

That's it for today. Many thanks to Richard Epton for use of his tools.



Tuesday, February 08, 2011

Coppering the radiator brace

Spent a few hours at the shop today. The radiator support braces needed the copper installed. Since there was a curved cutout for the spark plugs, the first piece of copper covered the curve.

Then the sides were installed. I did this with one piece of copper.

Here is the finished end.

Then the radiator end was finished. This was much easier than the last end!

Here is the finished brace,

I was able to complete both braces and add copper to the ash seat support piece too. All three pieces are now quietly drying after a good coat of varnish.

More soon. Enjoy


Monday, February 07, 2011

Fuel tank and fuel gauge

We decided to work on the fuel tank because I wanted to permanently mount it in the fuselage. Two gaskets were cut from some cork gasket material purchased at the local auto parts store.

The gasket between the tank and the spacer was coated with Permatex #3 to ensure a good seal. Because the fit between the spacer and the fuel gauge was really good, the upper gasket was installed dry.

Here is the fuel gauge in place. Also notice the fuel cap - the vent was attached to the cap using JB weld.

Now, the big test! We took the tank to the fuel farm and filled it up.

No Leaks !! I was really happy. I wanted to make sure the tank was sealed because later in life, if the fuel tank had to be removed, the upper wing would have to come off and the center section removed.

Oh, yea. And the fuel gauge worked too.

We spent the rest of the day working on the cabane struts. More about that later.