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Building a Mustang II
Left fuselage skin riveted PDF Print E-mail

On schedule with a short term plan - Left forward fuselage skin riveted in place on Friday! 

 

Left fuselage skin riveted in place.
 

 

After finishing the riveting we flipped the fuselage vertical for some more work on the underside of the airplane.  First up will be fitting the landing gear torque tubes, then after that will be the inboard aileron push-pull tubes.  After those are fabricated and installed the bottom wing skin will get riveted in place and the fuselage can get flipped horizontal again to install some skin stiffeners, roll bar, fuel tank mount components, baggage floor and then it's on to the tailcone assembly.  That's when it will really start to take up some shop space!  It's nice having it vertical for a bit as it makes the shop much roomier.  Where it was sitting before the firewall was protruding right to the centerline of the shop and made it a tight squeeze for working on vehicles.  At least when I build the tailcone I'll be turning the fuselage orientation so it won't take up as much "working space"

Fuselage flipped vertically

 

New spot to work on the fuselage.

 
A long overdue update! PDF Print E-mail

Well for those who have been checking in you all know it's been entirely too long between my updates.  That stems from the fact that many other homebuilders have stated in the past - life gets in the way.  However despite my updates being few and far between lately, I have still been making progress on many things.  Starting earlier this year I began assembling a 1/2 VW engine for the 2nd airplane project I've decided to start on - a Legal Eagle ultralight.  It's a cheap airplane and it just looks so darn fun to fly.  Grass roots aviation at it's best!  I now have the engine completed and have test run it and it's ready for final tuning to calculate it's horsepower.  It's construction was not without it's own slight diffuculties, but all have been overcome.

 

Legal Eagle 1/2 VW engine

 

The hardest part in getting the engine constructed was getting the crankshaft balanced.  I deviated from the standard 1/2 VW plans as I went with an 82mm stroker crankshaft which required leaving an extra counterweight on the crankshaft at the end and moving the thrust bearing up to the nose of the crank behind the prop hub (which I prefer actually).  The problem was the crankshaft was then so short with such a small rear bearing journal to fit in that I couldn't find any engine shops able to spin the crank for balancing.  I ended up working with Fond du Lac Auto machine in Fond du Lac WI to build a set of Vee block bars for their machine so we could balance it.  I made the bars from 1/2" 4130 steel bar and machined a V in each block on my CNC machine.  Then I machined a pair of teflon shoes to sit on each side of the V and pinned each shoe to the bar with a roll pin to keep it in place while the crank is rotating.  I was happy to see the bars worked flawlessly and that consecutive spins of the crank were all completely repeatable to well under 1/10th of a gram during the coarse balancing, and even more accurately repeatable during the fine balancing.

 

1/2 VW crankshaft balancing.

 

I had the engine assembled just before Oshksoh 2011 but didn't fire it up to run it until after Oshkosh was over.  After Oshkosh however we found out that both of my grandparents were given a life expectancy term due to cancer.  Upon this news I decided I wanted to do something special for them and so I put the airplanes on hold to start a new project.  My family is a long line of farmers and farming was my grandfathers life.  The first new tractor he ever purchased was a 1952 Case model D tractor.  We still had that tractor parked in a shed here and I decided to pull it out and fix it up as a surprise.  It had sat for about 10 years and the engine was tight from a coolant leak that developed in the #4 cylinder.  It was also quite rusted so you couldn't make out much of the original color in most places.  After the engine was cleaned up, re-honed and spinning freely again I went on to fixing up the body work.  The entire tractor was sand blasted with my pressure sand blaster and given a fresh coat of primer, followed with a layer of body filler to smooth out all of the small rust pits.  Then another coat of primer followed by the top coat of paint.  Start to finish was just under 1 month, and it was completed in time to trailer to town to surprise both of them.

 

Case D tractor

 

After that job was completed I took a little time off to relax from the hectic schedule.  It also left the shop in quite a mess as my emphasis was more on getting it done in time than keeping the shop clean so a thourough shop cleaning was in order.  But with that completed I'm happy to say I'm back to the airplane building!  Today I got the passenger side fuselage skin riveted in on the Mustang II with some help from my friend Dan.  Next up will be the pilots side fuselage skin which I hope to get to on Friday.

 

Legal Eagle fuselage skin

 

 After the fuselage skins are riveted on the Mustang II I will be flipping the fuselage vertical to work on the main lainding gear torque tubes and rivet on the bottom wing skin.  With the fuselage in the upright position I will start on the fuselage for the Legal Eagle so I can convert the tubing into something that can fly!

 

Legal Eagle fuselage tubing

 

 Onward and upward!

 
Assembling the forward fuselage PDF Print E-mail

Well it's been a little bit since my last update but I have been making progress.  I've now got the side fuselage skins trimmed to a final fit aside from over the flap and have begun assembling the forward fuselage.  The firewall is now all squared up, my engine mount channels are all bent up and I've begun attaching the engine mount extrusions to the engine mount channels to start getting everything in it's final home.  It takes a little while to get everything square, level and straight but it's not too horrible.  I've got the top engine mounts/channels in place aside from getting drilled to the skin/stringers.  Next step is to drill the lower mounts/channels and then I can start on the lower tunnel assembly and then bending the lower edge of the skins to their final home.  After that it's dril drill drill, followed by deburring and dimpling and countersinking and then a bunch of rivet bucking!  I'm still hoping to get the skins ready to rivet by about the end of February, and by the end of March I'd like to have it moved to the corner of the shop and making progress on the tailcone.  I'm hoping to have it off the jig and on the gear near the end of June or July.

 

Mustang II Forward Fuselage assembly

 

 
Getting some skin! PDF Print E-mail

Well I've finally made it to the point of being able to cut out the fuselage skins and have the firewall assembled.  It's starting to really make it look like I'm making some progress and it's getting easier with each day to visualize an actual airplane being assembled.  I've made the marks for the centerline on the floor and so the next step is to mark the horizontal reference line on the fuselage bulkheads and attach the top fuselage strings in place.  After that I can clamp the fuselage skins in place and then make the engine mounts/forward formers so I can clamp in my firewall and get everything lined up.  To see more images of the progress check out the Image Gallery!

Mustang II Fuselage Skins

 
Getting back in the groove PDF Print E-mail

After a long break I'm getting back into the swing of things.  It's been a busy summer and as typical life happens!  But it's been a summer of a lifetime.  Getting married at the EAA museum, a road trip with my wife down historic Route 66 (by car, some day we'll return by plane!), a week at Oshkosh with friends and all the good company it brings plus all the usual yardwork etc so it's not all fun and games.

But now with the weather dipping down below freezing and the outside yard work slowing to a slow crawl I've been able to get back to building on the Mustang!  I still intend to have it on wheels and rolling around by spring time.  First up on the list is to assemble the firewall and as soon as that's done I'll be cutting my fuselage side skins.  That should make it feel like a lot of progress in a (relatively) short amount of time!

The excitement is building! (no pun intended)

Mustang II Firewall

 

 

 
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