"cavelamb himself" wrote in message
...
Ed Huntress wrote:
"cavelamb himself" wrote in message
...



Wow, I've read for years that the VW was not a good conversion, but I
didn't realize it was that bad.




Anybody who wants to see the details of my planes...
the plans and builders manual are at:

http://www.matronics.com/photoshare/...006/index.html
Scroll down to the Plans download - or the manual download.
Heck, splurge and get both!


Photo CD of construction log web site and lots of pictures...
http://www.matronics.com/photoshare/...et.03.04.2006/

Warning Will Robinson! - MOBY BIG Zip file...


I didn't download your big file but I see some photos on the Web of the
Texas Parasol. I see it's made of 6061 aluminum angle and tube. How do
you stick it together, TIG welding?

--
Ed Huntress

Rivets, Ed!
AD-470 type driven rivets.

While 6061-T6 can be welded, such would never do a fuselage truss.
That sweet curve would turn into a series ov straight chords.

Ug...


Yeah, that's why I wondered. I couldn't picture welds that wouldn't make
a mess.

But the frame members appear to meet at points, as in a tubular space
frame. How do you get rivets in there? How many rivets pin a typical
joint?

--
Ed Huntress

Extruded angle - mated on the flat faces.

The vertical members attach to the outside (vertical) longeron flange,
the horizontal members attach to the horizontal flange.

Everything attaches on the inside face of the longeron - well, except
the landing gear cross bars / lift strut attach points (a pair of 1-1/4"
extruded angle pieces) that are bolted underneath the longs.

Edge margin is a little iffy with 3/4" flanges, but the 1/8" thickness
(each) is more than adequate metal to hold a rivet.
It's not like riveted thin sheet metal.
More like Lugs.

Some use two 1/8" rivets per joint - some use a single 5/32 or 3/16.
I've done them both ways.

It produces a very rigid, fairly light weight structure that is very
robust.

For example, a Graham Lee Nieuport fuselage the weight increase is
about 6 to 8 pounds.

A very slight factor compared to the structural integrety, low cost
and ease of construction afforded by extruded angle construction.

That's interesting, and surprising. So, many of those members are held
together with a single rivet.

I'd like to see that one in a finite-element analysis program.

--
Ed Huntress