Christmas came early!

On December 15, 2012 I walked into the work area and found the following four guys looking at our new spars!!!!

We now have 4 spars, two front and two rear; enough to finish both the left and right wings, yippeeeee!

Joe found a cabinet maker that has a CNC machine, which drilled the holes with almost perfection. So, now it is a matter of putting the ribs, compression struts, wire bracing, ailerons, doodads, and flumdittys on the spars. It's going to get interesting; well, it has been interesting, but now it's going to get really interesting.

Left to right, Paul, Leo, Joe, and Rishab (aka the new guy).

When it rains, it pours: New guys

Wow, three new people visited today (Dec 15, 2012)!

Below is a photo of John Schwarzkopf. John is taking on a project that was previously stalled. We have thousands (yes, thousands!) of model airplanes that we would like to sell. They have been put into a database and sorted. Then nothing, until John came along and volunteered to put them on ebay. He takes a couple at a time and takes photos, writes descriptions, posts ads, mails the models, and finally delivers MONEY to EAA 143. Cooool!

Who would've thought that ebay expertise would be so valuable to our glider project. The money that comes in is going toward our spar purchase, which is currently holding up our wing project. So, thank you John!

Two other visitors today:

John Kraft's grandson Gregg visited. Young blood--Fantastic! We need all ages, but right now we are heavily weighted towards the senior citizens. Moral of the story, if you are a young or old, or somewhere in between, come on out. Everyone is welcome.

Rishab Shyam also visited. Rishab just earned his private pilot license earlier this year, and now wants to learn about building airplanes because someday he may want to build his own. He flies a rental often, and will be in this area for another year or so while he finishes his PHD in biomedical engineering at John Hopkins.

Compression Struts

What is a compression strut?

A compression strut fits between the front spar and rear spar (in each wing) and holds the spars the correct distance apart. They are in "compression mode" which means the spars are pulled together by criss crossed wires under lots of tension. So the only force the compression struts provide is, duh, compression. The wires also provide the force needed to keep the struts from moving laterally, more on this later when I can take some photos of the completed wing.

Two of the compression struts

Mechanical drawing of the compression strut, at one end.

The two pieces that will form one end of the compression strut, as seen in the mechanical drawing.

Note: the sheet metal was cut, deburred, and bent by Paul Straney. He had to tweek it very carefully because the fit has to be close to perfect in order for the welding process to work. Both pieces are thin metal, and there is little room for error when welding.

OOPS!

This rib had a small defect. Look at the gusset at the top center.

The gusset was not pushed all the way to the edge of the rib, and so it did not provide all the necessary strength. Part of the gusset has been removed by Leo. He will remove the rest with sandpaper.

After sanding he spread epoxy and placed the new gusset in position.

Bing, bam, Done.

Time for Lunch while the glue dries. The subs were made fresh on the spot by Joe. He usually makes an extra one, so stop by and join us.

Fuselage update

Joe Miller asked for some fuselage photos that he could take to Oshkosh, so I took these for him. It was a good chance to move the frame to a clear area and piece it together. It actually looks pretty good (thanks to much work done by Paul Straney). The fuse is now in three pieces, the main fuse, and two small tail sections. If you look closely you can see the gaps near the tail.

I want to comment on weight. It was easy for two people (Paul and me) to pick it up and move it. We each used two hands because of the size, but it was light enough that I could have used one hand if necessary. So, how can something so light support the weight of three adults, wings, and landing gear? Magic, or good ol' US of A design? 

Sorry, I couldn't figure out how to rotate the photo . . . .

Root Ribs Are DONE!

Yes, the weekly chipping away at the project does have it's payoffs:

Both root ribs, one right, one left.

Front spar slots and lightening holes.

Rear spar slots.

They are the same length, its just the camera angle :-)

Lots of gussets for strength.

Hi,

We didn't have a work day yesterday because of an airshow that most were attending. So, I thought I would take an opportunity to update you on the progress thus far:

All of the tubing has been removed from the fuse that is not needed. Now the extra tubing will be added.

Ribs are done except for the butt ribs.

Spars need to be ordered for the left wing (right wing later) at a cost of $650. If you would like help move the project forward, please consider making a donation. Thank you.

Do you speak Draftese?

Drawing has dotted lines. . . ?

The drawing has a set of parallel lines that was confusing for weeks (actually, it was probably months). According to Draftese, dotted lines means a hidden line, which means something is behind something and out of sight. Last week the guys had a brainstorming session and figured out that the something was, and realized it was a reinforcement strip on the back of the rib. They then fabricated the strip and glued it in place as you can see in the photo above.

Chef Joe set up a production line for sandwiches at yesterdays work day.

I took this photo for John (in the middle, Dick on the left, Leo on the right). The photo will be used in an article that John is writing for the Martin Museum Newsletter.

Butt Ribs

First, I want to set the record straight. I asked around and found out the reason these ribs are called "butt ribs": they "butt" up against the fuselage. Hmm, I shoulda guessed. Oh well.

This photo shows the two butt ribs are coming along nicely. I included an old but rib from another similar Aeronca for comparision.

Closeup.

Note: I added the thin strip of wood to the photo that is applied to the top and bottom of the butt rib.

This is how the thin strip of wood is attached to the old butt rib. Note the slot for the spar.

Oops. someone made a notch for the thin wood strip. Not supposed to be there :-(

The good news is that Joe made a right and left butt rib, not two right ribs.

Even the tails of the ribs are made right and left.

BTW. I suppose that if Joe had made two right hand ribs, then we could have said that two rights make a wrong. Sorry, I couldn't resist . . .

Here Joe is filling the unwanted notches with wood strips. I like the clamps. My dad a pair of these, and when you need them (for an irregular shape), nothing else will do.

Closeup of Joe's handiwork.

Close up of old butt rib

Nice hole. 

Aileron Transition Ribs

Where the end of the ailerons meet the wing's full length rib, a special rib is needed.

Wing rib (cut short to allow for aileron).

Drawing of full length wing rib (i.e. no aileron).

Sorry, I didn't have an appropriate photo :-(

Transition rib.

Now, let me see if I can explain the photo of the transition rib. There are two wood pieces, one tan (on top), and one brown (on the bottom). The brown wood fills the rib and matches the wing where there is "no rib". The tan wood is glued next to the brown wood, and matches the wing ribs where an aileron is located. So, on one side of this transition rib is for an aileron, and on the other side is for "no aileron". Have I totally confused us yet?

Note that because the tan wood is glued to the side of the rib, it sticks out about a quarter of an inch. This is done so that a thin piece of material (wood or thin aluminum) can be attached to it. That piece of thin material is used to close the space at the back of the wing, just in front of the aileron. Are you confused yet?

As time goes by, the above explanation will make more sense. So, please stay tuned as we continue.

Jig: Gusset Cutter

Leo made this nice jig for cutting gussets in half. Lots of gussets are used on each rib, and lots ribs are used. So, if my math is right, lots of ribs X lots of gussets = gazillions of gussets.

A round gusset, and the jig are sitting on the jig saw, sorry for the pun.

\

Gusset is inserted into the jig. By design it only goes in halfway.

Jig is flipped over, and jig saw is used to cut gusset in half, guided by the edge of the jig.

Note the nice hole for pushing out the other half of the gusset.

Voila. The process is quick, and accurate.

If you look closely, you can see a piece of cardboard was glued into the slot to make a snug fit for the gusset so it didn't fall out during cutting.

Cool Photo

Paul found this photo.

The photo shows some of the training gliders used during WWII.  If you zoom in, you can read the printing.  The four gliders on the top right are TG-5s, which is the glider we are rebuilding.  The rest are a mixture of TG-19s, TG-15s, PS-2, TG-1, TG-2, and SGS 2-8.  Thanks Paul!

Problem: Wing Strut Bracket

This wing strut bracket is bent on the left side and will need to be straightened.

This bracket has not been damaged.

Bending the bracket may require some heat. Stay tuned.

Problem: Landing Gear Bracket

This is the mounting bracket for one side of the landing gear. Remember, the fuselage is upside down.

Yeah, ugly!

View from the rear of the fuse.

This will be a bit of a challenge. The metal is torn, and will probably have to be replaced (maybe just the left half of the bracket). The bracket is welded into the frame where lots of tubes are joined. Originally, holes in the bracket allowed the tubes to be inserted into the bracket, then the whole joint was welded. It will probably take quite a bit of fabrication (new bracket) and disassembly to make it suitable for reassembly and welding.

Center landing bracket.

This bracket resides between the other two. It is bent, and will need some straightening. Maybe some heat from a gas torch will help.

Success!

Front cross brace has been removed

Note: Paul has flipped the fuselage upside down to make it easier to work on, so it looks different from the last photos.

Now there is room for the instructors feet, ha.

A joint after the removal of the cross brace, lots of work needed (fill with weld).

Only a little bit of filling needed on this joint.

BTW, notice that the paint has been sanded to prep it for the welding. Sanding is used because it does not introduce any elements to the metal that could contaminate the weld.