SCAT Electronic News 20 February 1998

SCAT Electronic News 20 February 1998

CIAM Meeting
============

Bob Waterman will be attending the CIAM Meeting as an unoffical
delegate. The FAI Web Site has the agenda for the meeting.

I looked at printing or displaying it but it is hard to do because it is a
Microsoft Word Document with some special formatting that does not
show up well in E-mail or on the web site. So you need to go to the web
site to get it. For those not familar with web operation download the
version that is a self extracting archive and store it in a temporary
directory on your computer. Then run it as a program and the document
will appear. If you do not have Microsoft Word you can download a
viewer from the FAI site [or the Microsoft site].

There are a number of procedural items with regards to the running of the
World Champs, some procedures for checking F1A towlines, flyoff
clarifications for the mini events and F1C engine run items. Bob will be
prepared to help represent the US FAI Free Flighters point of view so you
need to e-mail him at This email address is being protected from spambots. You need JavaScript enabled to view it. if have input.

Note that official US Delegate at the meeting is Dave Brown in his
position as the AMA President. In the past the AMA president has always
looked for advice from the different specialists in each discipline before
voting.

Correspondence
==============

From Martin Gregorie


Roger,

This is just a note to say that the woven carbon braided tubes that Gerhard
Aringer has is the stuff that we refer to as 'carbon sock'. I can confirm
that it is good stuff. Mike Woodhouse sells it in the UK.

To use it you'll need to glue soft balsa guides to each end on the spar to
stop snagging. Then you just slip it onto the spar, pull it a bit to snug it
down, wet it out with epoxy, blot and cure. I cure under tension with the
spar wrapped in release film and clamped in both directions to compact
the
carbon. You can also use heat-shrink tube or vacuum bagging to get good
compaction. The critical point is to get good flat surfaces top and bottom
of the spar so you get good adhesion to the D-box.

Unlike Gerhard, I pull the sock over the entire balsa plus carbon flange
spar assembly while he puts the tube around the balsa filler with the
flanges on the outside. I think there are pros and cons to each way of doing
it - I prefer the reduced spar delamination chance gained by socking the lot
and will risk a possible worse spar:D-box joint as the lesser evil.

The best weight for F1A spars is the 4.2 g/m tube.

The lightest grade is also used by F1B fliers to form tubular stab spars.

Regards,

Martin Gregorie


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--
Roger Morrell