Narfi's Zenith CH750 Super Duty

[narfi]

Lots of stories of guys who built their own plane and few it for years, then when they got old chopped it up to prevent someone else from flying it when they died.

Rutan really got the whole homebuilding composite planes popular and I really like his designs and the sci-fi romantic feel they bring. But that was an era without internet and easily followed tutorials and blogs etc..... and much less ability to communicate with a designer or to know how well their designs had been tested.
The advantage to that era was that people were less fearful of their shadows than now and more likely to attempt something so impossible as building your own airplane.

My income is derived from 20 years of experience and the ability and qualifications in inspecting just this sort of structure. I do not have the mathematical and engineering education to design something like this safely, but I (feel like) am overqualified to build something like this according to blueprints and plans. As cocky as I may feel about it though, I have access to and will use a few eyes with much much much more experience and wisdom than me.

[Jeff]

Good stuff Narfi!!!! I will really enjoy having an airplane build on the Forum!!! Jeff

[narfi]

Made the cutting templates and form blocks for the rest of the horizontal and elevator parts this weekend. Still waiting on the .016

Sent an email to Roger asking for more parts to make.

Roughly 6hrs

20201026_064221.jpg (79.3 KiB) Viewed 1158 times

Total time spent building: 17 hours
Total Cost: $8276
Airplane + consumables + project specific costs: $5340
Tools, etc.. I will keep for future projects: $2936

[narfi]

Getting colder, but at least with this project I can put on a coat and gloves and still do something. When working on the boat I had to close up in September till spring because it was too cold for epoxy.

Got a lab coat I've been wearing its a little snug over the winter gear but still fits until I add another layer. Has worked well at keeping my cloths less dusty with sanding and routing the aluminum.

Talked to Roger yesterday, he still doesn't have a big list of parts for me yet but said I could do the flaperon, slats, and rear wing ribs.

Took me about 2 hours last night to make the cutting templates and form blocks for the slats ribs. In my head thats a 20min project..... but in reality im not as efficient as I imagine :p

20201030_065753.jpg (58.36 KiB) Viewed 1158 times

Total time spent building: 19 hours
Total Cost: $8276
Airplane + consumables + project specific costs: $5340
Tools, etc.. I will keep for future projects: $2936

[Jeff]

Narfi, how cold is it now? Jeff

[narfi]

The mountain is white, and the puddles are hard.

[Jeff]

Got it!!! You guys take good care!! Jeff

[Netpackrat]

Dunno how cold it is out where Narfi is at, but it's unseasonably $#%*^& cold in Anchorage right now. Last night had a badly cut tire on a returning aircraft, and a broke bird already in the hangar so had to change it on the ramp. Not too big of a deal even with the cold, but got the wheel off only to discover the brake leaking. Tire AND brake change plus cold ramp plus wind chill equals no fun at all. Ended up putting my heavy Carhartt bibs on. I have never put them on in October before. I only brought them back to work for the season a week ago, just in case.

As far as working efficiently goes, sheet metal building/fabrication is a related but different skill set compared to sheet metal repair. Another thing is it is difficult to be efficient when you are building aircraft in quantities of one. As you get into repetitive tasks like making wing ribs, etc, you will hit your rhythm and eventually not waste much time. Then as you tackle different parts you get to figure out the most efficient ways of making them all over again. Often the simple and tedious way is more efficient overall than spending more time getting tooled up to make something using a more time efficient but tooling intensive method. Other times it is worth tooling up even if it is the slower way of doing something. I went to the trouble of making drilling jigs for the multitude of rib stiffeners the bearhawk has, even though it slowed me down a little making them, because when it was time to do alodine and primer for corrosion control, I had bags of interchangeable parts that could be batch processed, rather than a series of matched sets I had to keep straight, so it saved me a bunch of time overall.

[BB Sig]

I use to work on CH-47s "phasing" the aircraft. Think 200 hour check. I was the bottom of the aircraft guy and changed a lot of brakes and tires. I'd hate to do it in the cold and dark. Headlamps are for sure your friend...

Great project and just keep eating the elephant one bite at a time.

[narfi]

It was suggested on the homebuiltaircraft forum that the skins will fit tighter if temperatures stay the same when drilling and riviting so the aluminum isn't expanding and contracting. I'll try to do my drilling and assembly at steady temperatures, but should be ok making the parts in the cold.

3 more hours got me the cutting templates and bending forms for the flaperons.

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Total time spent building: 22 hours
Total Cost: $8276
Airplane + consumables + project specific costs: $5340
Tools, etc.. I will keep for future projects: $2936