Yesterday I received perfectly milled parts for my Hafner.
Couldn't resist an instant test fit. Perfect tight fit, no glue required to hold things together.
I forgot a few cutouts in the design which I had to do by hand. Took me 10 min.

Unboxing and test fit

Hafner AR III unboxing and test fit (9 min 17 sec)

Nice to see how it all comes together

Kind regards, Kuni

I am going to try to document the building process as fully as possible with the camera.

Hafner AR III build 15 May 2020 (5 min 16 sec)

Hafner AR III build 16./17. May 2020 rear fuselage (12 min 19 sec)

Hafner AR III build 16.May 2020 horizontal stabilizer (4 min 39 sec)

Hafner AR III build 17. May 2020 horizontal stab no. 2 (3 min 10 sec)

OK. that's about as far as my plans went, now I need to start improvising or go back to the drawing-board

I am working on the rotor head and bearing.
Completely unreasonably I decided not to use a tried and tested design but try something different.
the idea was to make it more simple. I probably failed there.

the base of the design is a spherical bearing produced by Igus an company specialized in plastic bearings.
https://www.igus.co.uk/product/389
The bearing is supposed to take forces of up to 1200N in axial direction. Thought this should do for my model.
I need to add a pin to prevent rotation around the axis.

Rotorkopf (0 min 35 sec)

All grey parts in the animation are aluminium, dark grey is a 608 ball bearing and blue is a 3D printed seat for the spherical bearing.

Any comments /thoughts / critique is highly appreciated !!!

Thats about what it is supposed to look like when attached to the model.

Good thinking...I like the idear...very compact.
Chris...

Started building the rotor head design.
Donīt take it as a tutorial! I am rather incompetent in working metal.
fortunately it is a job that does not require micrometer precision.

Hafner AR III build 01. June 2020 (4 min 6 sec)

Craftsman at work
Joe

I like ...........
Chris...

ongoing work at the rotor head and bearing. Here you see parts of the building of the rotor axis.
and a lot of "how not to's"

Hafer ARIII build 18. June 2020 rotor axis (4 min 48 sec)

build of the second prototype of a yoke (??) for the linkage of the rotorhead.

Hafner AR III build 19. June 2020 bending the rotor head linkage (6 min 25 sec)

I rediscover that it is not only possible to solder aluminum but it is even relatively easy to do.
I decided to solder the distance tubing to the linkage yoke to reduce part number and hopefully increase stability

Hafner AR III build 19.June 2020 soldering the head linkage (7 min 32 sec)

Started with the undercarriage

Hafner AR III build 20. June 2020 undercarriage attachments (10 min 36 sec)