Nev=0AI like your technique wetting the carbon, my only difference is that
I use industrial cling film instead of polythene.=0AMuch easier to squeegee
.=0AGraham=0A=0A=0A=0A=0A________________________________=0A From: Neville
Eyre <neveyre@aol.com>=0ATo: europa-list@matronics.com =0ASent: Wednesday,
23 October 2013, 22:29=0ASubject: Re: Europa-List: Re: MOD 78=0A =0A=0A=0AH
i Dave,=0ATo do the job properly, you are going to have to take out the ail
eron and airbrake pushrods anyway, so not much more of a job to grind / swe
at off the tufnol block at the same time. Take measurements as to where the
block is so you can replace it in exactly the same position. Best to keep
to what has been tested / proven ?=0AMake up some sort of jig so you can fi
nd the hole for the aileron belcrank pivot after the tang has been covered
with the carbon wrap [ you will need a longer bolt =0Aafter the wrap ?]=0AT
he Instructions imply the carbon cloth goes into and ends in-the corner,
I didn't like all that extra stiffness stopping in one place, so I took the
4 side plies [ front and rear face] around the corner, onto the root rib,
-stepping them off at 2'', 1.5'', 1'', .5'', and finished the 4 wraps-i
n the corner.=0AHere's the tip regarding laying up the carbon cloth.... car
bon is black and shiny when it is dry, and black and shiny when it is wet,
so how does the laminator know if he [ or she] has got it all wet ?=0AWeigh
ing out the cloth and using the same amount of resin is one way, but there
may [ will] be areas that will end up too dry, especially if wetting it uph
ill from underneath....... where a fair amount of resin-will go up your a
rm !=0AGet some medium weight clear polythene sheet. Wash / wipe any releas
e film contaminates off with paper towel and acetone.=0AMake a card templat
e for the side plies, and the wrap plies to use to draw round.=0ADraw on th
e- finished shape of each lay up onto the poly' with a ball pen, do this
for every individual ply, and cut them out with a couple of inches to spare
all around. Cut out the same number of blank- pieces the same size.=0ATu
rn the poly' over onto a poly' covered bench so the pen ink is on the under
side, place the precut [ slightly oversize] carbon cloth on top of the- p
oly', so it overhangs the pen line, and pull the fibres about to get it all
square and even. [the carbon is far-looser in weave, it goes out of shap
e easier, but not as soft to go round corners.]=0AWet the carbon cloth init
ially with a brush, dibbing rather than brushing so as not to disturbthe we
ave, when it is wet and stuck to the poly', give it a gentle go over with a
foam roller. Cover that with one of the plain sheets of poly', and squeege
e through the poly' so it goes clear and you can see no dry weave areas thr
u it. Flip the poly' cloth sandwhich over and squeegee it on the other side
until there are no visible dry weave areas, you can chase the exess resin
about to wet out any dry areas. Once it looks all wet, squeegee quite hard
to wipe out the exess out of the sandwhich, and scoop up that resin off the
bench back into your pot.=0AFlip the sandwhich back over, and cut through
all of it with SHARP scissors, to the pen line which will just about be vis
able in good light. Bin the offcut, you now have a poor mans prepreg ! Peel
off the poly from the side you want to stick it on, and you can carry it o
nto the job, it won't stretch / sag / and can be placed and removed until y
ou are happy with the position. Squeegee it through the poly and chase out
any air.=0APeel off the poly', and then roll over the carbon with a roller
made from plain and spring washers, to get all the air out and really mash
the cloth onto the surface.=0AWipe off the poly' covered bench to remove al
l resin, and start again. You will need to put on new gloves for each ply,
as you won't be able to smooth / stretch the cloth about with sticky gloves
. Reckon on using a couple of gallons of acetone, 2 or three paper towel ro
lls and 200 gloves for all of this, with all the poly' off cuts and sheets
you will fill 3 dustbin liners !=0ADo a trial poly' prepreg before the real
deal, to get the hang of doing it, really makes it easy compared with tryi
ng to juggle with the cloth and wetting on the job. Ensure there are no cre
ases / wrinkles in the poly, tailor the ink lines to miss any.=0AGood luck,
=0ANev=0A-=0A-=0A-=0A-=0A----Original Message-----=0AFrom: djaflyac
t <djaflyact@gmail.com>=0ATo: europa-list <europa-list@matronics.com>=0ASen
t: Wed, Oct 23, 2013 1:47 am=0ASubject: Europa-List: Re: MOD 78=0A=0A=0A-->
Europa-List message posted by: "djaflyact" <djaflyact@gmail.com> Thanks Ne
v. I have ground one spar tang today. Had to quit due to roasting in =0Athe
sun and just the mess of it. I'm wondering if anyone has done this mod on
a =0Aflying airplane. The reason I ask is that the speed brake control tufn
ol block =0Ais right there where the fiberglass is layed up against the roo
t rib. To grind =0Athose payers off the root rib, I would ahve to remove th
e controls for the speed =0Abrakes and also the ailerons. What I was hoping
to do is leave the fiberglass on =0Athe spar out about 2 to 3 inches and t
hen add the new layers as called for in =0Athe build manual, but only run t
hem up the root rib where possible. Otherwise, =0Athe new plies would essen
tially splice onto the existing pile on the root rib. =0AWhere I can run th
em up the root rib, it would be thicker than called for in the =0Amanual. T
here is also the issue of the glass that is holding on the wing root =0Afai
ring, which is why I'm asking about not taking off the layers that are now
on =0Athe root rib. I'm still getting lost in the terminology - roves - tow
s, etc. Is there a source =0Aon the internet that defines what these terms
mean? I'm attaching a photo of it now, with the intensifier board on top fo
r scale. Oh - How far does the carbon fibre cloth go toward the rot rib? AL
l the way to =0Athe 90 degree corner? Off to shower off the dust - you are
right - it goes everywhere. I am wearing a =0Aspace suit and I still get it
on me. Dave PS On one spar, There was a spot of somthing that looks almost
like sap in a =0Aspot when I was grinding the shear web layers - toward th
e wing root. Like a =0Apocket of sap or a pocket of something that was not
cured. This is about a 12 =0Ayear old spar. Read this topic online here: h
ttp://forums.matronics.com/viewtopic.php?p=411138#411138 Attachments: htt
p://forums.matronics.com//files/grinding_done_196.jpg arget="_blank">http
://www.matronics.com/Navigator?Europa-List=0Atp://forums.matronics.com=0A_b
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