Airframe apprentice at 73

[MBfreak]

I have joined a club of very skilled airplane mechs. All have worked with the development and prototype manufacturing of SAAB jet fighters for the Swedish Airforce.
They needed somebody who could handle the electrical/electronics, I was invited.
They rebuild planes that will only be displays at a museum and never flown.
The electrical/electronics is very simple , and I asked to be an apprentice to the fantastic airframe guys. Presently working on an all aluminum Grumann Goose sea plane that spent 15 years in shallow salt water.
Much corrosion, and my task is to drill out a large amount of rivets and cut out corroded aluminium panels.
The shop has fantastic tools and the airframe guys are super skilled craftsmen.

Ola

 

[Bighead38]

This could be cool.

 

[Ohmthis]

This looks awesome! Keep updating this please. I see in the one picture the windscreen of the cockpit, is the other picture the bottom? Will it be airworthy when done?

 

[Itsjustdirt]

Very cool! Please post more pictures and info and it comes!

 

[MFolks]

www.browntool.com has many specialized aircraft assembly tools,along with other websites. I used to build missiles in San Diego at General Dynamics/Convair in San Diego 1983-1993.

 

[MFolks]

#30,40,20,and 3/16" drill bits, clecos, air drills, 2X,3X, and 4X rivet guns,bucking bars,all familiar tools to me.

 

[Kevin54]

Enjoy the experience. We have a small museum just a few miles from me that has volunteers restoring a B17 and others. https://www.champaignaviationmuseum.org/about

 

[captain14]

This could be cool.

This will be cool.

 

[crucible]

That's awesome!

 

[OccupantRJ]

More than one way to skin a Cat!

 

[cvairwerks]

More than one way to skin a Cat!

Other than it's a Widgeon or a Goose... A PBY is about 4 times the size...If it floats and flys, it's a blast anyway.

 

[KMinAF]

Proof that you are never too old to learn new skills!

 

[MBfreak]

My ticket to being invited was electronics/electrical knowledge.
Did a bit, but at 73 it is hard to get excited by an old radio that needs a bunch of capacitors and a tuneup.
But the radio out of a Mosquito that was used as a post hole digger seems to be a challenge!
I much prefer being the apprentice rivet remover!

Ola

 

[kbs2244]

Not often the a radio repair includes metal to be straightened.

 

[MBfreak]

The airframe ace is off for a couple of weeks. I do not feel competent to do repairs with him absent.
So I got the chance to do something that I am moderately good at.
A 1941 radio was found in good condition, the Museum wants to have it working on a display. Part of a complete radio setup ( transmitter, antenna tuner, motor/generator power supplies and lots of small stuff) The receiver is the only part found, the rest probably sits at some radio amateurs HQ, the transmitter was 1,8 kW.
All tubes missing, 1930´s vintage, hard to find. But overall condition is fantastic so I will get it going with a modern power supply. Eats 27 V, 310 V and -72 V.

Ola

 

[2oolhound]

Way to GO! Apprentice at 73!
Maybe there's hope for me yet.
but then, you Swedes....

 

[chrismenke]

First radio I've ever seen with a chain drive.

 

[MBfreak]

Chrismenke
Q First radio I've ever seen with a chain drive. UQ.
And not only that, it has a small motor with a fancy gearbox so that the tuning capacitor can be run remotely and also the waveband switch, traditional 4 position rotary. Magic performed by electrically operated clutches.
The radio is used either by twiddling the buttons manually or from a remote position thru pushbuttons.
The hunt for tubes is on, then starts the testing. I do not believe there is much wrong with it. The few electrolytic caps are wet type and most every other cap is either mica or ceramic. Some wax impregnated paper that tend to increase in capacitance by 50% over the years as the wax evaporates.
The ganged band switch has gold plated contacts.
Ola

 

[ddawg16]

Ok....following this thread.....

My brother-in-law buys and sells war birds. (I have a piece of Glacier Girl)

MB....does the group have a web site? My BIL might be interested.

 

[ZRX61]

On the avionics side, you may want to talk them into a chalk blasting set up for their media blast cabinet... These came out of a Norwegian Fjord (Ju-88):

 

[joeswamp]

That's really impressive. What are those things and how well do they work now?

 

[MBfreak]

ZRX.
Much impressed by the chalk blasting result for the JU88 power distribution module.
Unfortunately not much hope for the compacted and corroded radio that was in saltwater in a tropical climate. The various metals in a saline , warm solution has resulted in electrochemical destruction of many parts. Remowed an IF transformer and the copper winding had totally disappeared .
The crash damage is also very extensive.
But the 1941 Swedish Air Force radio in the later pic will be restored and run from a homemade mains power supply.

Best regards

Ola

 

[MBfreak]

ddawg16
Yes there are homepages but all in Swedish
ofsflyg.se
flygvapenmuseum.se

Ola

 

[MBfreak]

After having drilled out thousands of alu rivets and cut out square feets of corroded alu skin I finally was let loose, under supervision, to try to make a new section in a rib. Part of the job was made on a bench, which made it real easy.
Installing it with just 4" on each side when drilling and riveting was a lot more challenging.
Leif, the master craftsman, inspected and approved.
So now comes the real hard part, replacing the surface part cut out. Drilling, fitting and riveting will be a challenge. One person on the outside with a pneumatic rivet hammer, and one person on the very cramped inside with a heavy rivet anvil. Rivets are 3/16" half hard alu.
Will be fun.

Ola

 

[MBfreak]

The radio is under intensive care, and actually works, a little bit.
Spent a lot of time getting the mechanics in order. Lots of dried up grease and also corroded switches for the waveband stepping. Input male 14 pin contact beyond salvage.

A friendly radio museum donated a complete set of NOS tubes!
Checked all connections very carefully and then fired up the series/parallell filaments on 27 V
No problems. Applied 150 VDC with cold tubes, leakage current was around 1,3 mA and 2,1mA at 250 VDC.
Radio has only headphone driver so connected outboard amp.
Started the radio and there is life.
All tubes have about correct DC readings but tuned circuits, and there are many, are quite a bit off. But on dial setting 3200 kHz it picked up my signal generator set at 3500 kHz with 1 kHz modulation .
So now a long process starts to analyze and adjust every stage. Hope that the tubes are OK.
Lots of fun, to bring an 80 yo advanced airplane radio receiver back to life, even if a lot remains.

Ola

 

[Miss the Pontiacs]

MB good for you! Should be great for for the experience alone.
Make sure you keep us in the loop.
One question. What are you going to do once you grow up!

 

[MBfreak]

I grew up hard and fast in the sixties. Working half time in an industrial shop and studied for my MSc at the same time. 18 hours days , 7 days a week, 5 years.
Then, with a degree in electronics, I was made Chief Engineer of a service department with around 20 guys, all much better and older than me.
Somehow made it and continued with other challenging work.
Since turning 50, 25 years ago, I am devolving, and now about 20 years old again, at least some parts.

Hope to die with ZERO responsibilities, but not right now!

Ola

 

[larry4406]

Ola! Excellent!

 

[MBfreak]

Hi to all.
Yesterday the shop where we restore the Grumman Goose was closed as well as the museum.
Doors and gates were locked. The place is another victim of coronavirus.
So no updates for some time, guess around 3 months.

I use math to follow the trend of new cases, the exponential factor for the first 30 days is around 7. Will most likely flatten out a bit.

See you all in a bit.

Ola

 

[Provincial]

Best wishes to you Ola and all your compatriots! It is great to see the Goose being brought back. I worked on one in Alaska in the 1980's. It mostly delivered sport fishermen to lodges in Southwest Alaska.

We had to change an engine on it in a tundra pond one time. We were flown in on a DeHaviland of Canada Beaver floatplane. We built a working platform by sinking empty 55-gallon oil drums and adding a plywood-covered structure of 2x6's. On the platform, we made a tripod of 4x4's and lowered the P&W R-985 down to the platform with a lever hoist and rolled it onto the tundra on it's outside diameter. A helicopter brought in the replacement engine and hauled off the failed one. We reversed the process by rolling the replacement engine onto the platform and hoisting it into place. I took two days and the pond was drying up fast. The Goose was dragging bottom when it flew out, and barely made it!

 

[MBfreak]

Provincial.
Engine swap in a tundra pond! Great.
The Goose is on hold, shop and museum both closed until ???
Will post some news when situation begins to normalize.
Ola