Not commenting on chemistries, but if we are talking about the rear lift
sockets,
it is my understanding that the rear pins are under tension during accelerated
flight (like a pull-up) preventing the wings from folding forward.
Cheers,
Pete
A239
On Jun 2, 2013, at 9:09 AM, Tony Renshaw <tonyrenshaw268@gmail.com> wrote:
>
>> Gidday again,
> I've already received a private message telling me of other airframes with the
problem of the lift pin plates being in the wrong place within the fuselage
moulding. Comment was passed about the suitability of car bog, polyester based,
with our epoxy layups, and the PFA's view of its suitability under compressive
load. Anticipating some negative commentary I would like to make the following
respectful comments. Those doubters I'd like to ask, have you ever tried to
remove car bog from something? My lower fuselage jig is bonded to the floor
to keep it level and true. I needed to use a chisel and a lot of effort to
remove
it. Now a chisel is a very concentrated force, and I can guarantee the load
exerted by the fuselage facing "face" of a rear lift pin socket would need an
exorbitant amount of force to compress an entrapped amount of this polyester
resin based filler. Also, once encapsulated in 4 plies of BID, whether it
sticks
to the BId or not, my belief is it will be there !
> forever. I believe there is a greater likelihood of it being there in 50 years
than plywood. Why didn't Europa use it as a medium in their manual? I believe
because it was possibly overlooked, and did not have a historical base in
aircraft
structures. Personally, if it is inert, doesn't age or shrink, is easily
workable into complex shapes, or be sanded and shaped into such, I'd be happy
with it in my bird, with my kids on board. So, a bit of a vent really, but I
am irritated I have to use an in exact method on some preconception it will be
better, when I think it won't. Mind you, Downunder like the US, I am allowed
to make structural modifications. I'm tempted, but my conservative pilot nature
brings me here first.
> Regards
> Tony Renshaw
> Frustrated Aussie
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