Re: Quickie Q1 Canard and wing foam cut

David J. Gall

Flax is inferior to highly-crystalline cellulose fiber for exactly the reasons mentioned below. Highly-crystalline cellulose fiber is nearly equivalent to E-glass in all respects except weight -- glass is much heavier -- and in sanding -- glass is itchier. Highly-crystalline cellulose fiber is mechanically derived from what would otherwise be wastes generated in lumber processing industries and is marketed worldwide under the trade name BioMid by Gordon Shank consulting. The roving is used as twine (you know it must be inexpensive!) in the hydroponics industry so availability will persist for a long time for numerous reasons. BioMid is available woven into cloth in the US from Absecon Mills and in Europe from FRP Services & Co (France).

-----Original Message-----
From: <> On Behalf Of Rob de Bie
Sent: Thursday, September 16, 2021 11:04 AM
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.


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.


On Thu, Sep 16, 2021 at 8:16 AM Hot Wings via
<> <bd5er@... <>> 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.

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