-----Original Message-----
From: main@Q-List.groups.io <main@Q-List.groups.io> On Behalf Of Rob de Bie
Sent: Thursday, September 16, 2021 11:04 AM
To: main@Q-List.groups.io
Subject: Re: [Q-List] Quickie Q1 Canard and wing foam cut

Bob, when you mentioned flax fibers I peaked my ears! I've worked a bit with flax composites some 15 years ago. Is the material mature enough to use in an aircraft? I remember problems like no suitable sizings being available to optimize fiber-resin adhesion, moisture content during curing leading to degraded resin adhesion & quality, and moisture absorption during use leading to lower properties.
Sounded to me like it would a lot more development before it would be safe to fly. But it was 15 years ago.

I also remember reading in an eighties issue of 'Homebuilt aircraft' magazine that hot-wet test specimens could be good indicator of the longer-term quality of the fiber-resin adhesion. Sounded reasonable to me.

Rob

On 16 Sep 2021 17:39, Robert Cringely wrote:

Thanks! I’m using a no-name 680cc aluminum air-cooled V2 diesel to
which I am adding a tiny turbocharger and intercooler. What’s changed
since you looked is probably direct injection. Engine weight is around
50kg. I’m adding a belt drive from Ace Redrives in India. It’s 1:1
because I don’t need a slower prop but I do need to raise the thrust
line and to isolate the prop loads from the mystery metal Chinese
crankshaft. I’m probably a year from flying, by which time I will have
replaced most of the airframe with vacuum-bagged pre-preg. It’s not carbon or glass — it’s flax fiber, which fits right between e-glass and s-glass in performance, with a little Coremat added for stiffness.

Bob

On Thu, Sep 16, 2021 at 8:16 AM Hot Wings via groups.io
<http://groups.io> <bd5er@... <mailto:aol.com@groups.io>> wrote:

What diesel engine are you considering? I looked at the V-twin Chinese diesels more than a
decade ago and discarded the idea as not practical.
There are some interesting marine 2 stroke diesel development projects nearing market
introduction that may provide some of us with a 100LL option.

Look up Alan Thayer (sp) in the archives. He had an LS-1 canard designed using Graphlite
rods.Attached is a *.ZIP file of some of his work. Graphlite is no longer a practical source of
carbon rods for us as they are quite unwilling to sell rolled lengths of material. The Chinese
suppliers are willing and at a considerable savings in cost. Preliminary tests have indicated
the quality/strength is as good as the US sourced material.