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Old October 17th 06, 10:02 PM posted to rec.aviation.soaring
Discus 44
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Default Mylar Adhesive "Best Practices"


bumper wrote:
"Shawn" wrote in message
. ..
Gary Emerson wrote:
For the benefit of the group, let's hear about what works for
re-attaching mylar.

Now that we've established that the only solvent safe to use on a
composite glider is the sweat from a virgin Las Vegas showgirl,
can anyone answer Gary's question?

Thx,

Shawn




Hmmm, let me get the mental image here . . . Nah, ain't gonna find one of
those I bet!

I sort of thought we had answered Gary's question, but will add:

If the double sided tape has come loose in just one spot, simply pushing it
back down will not work or work for long. You might get away with raising
the Mylar seal and quickly wiping the detached surfaces with a Q-tip dipped
in Acetone. Then warm the surface and use pressure to re-bond the tape. This
will work for a while . . . but is not a long term fix.

If the debonded area is at the end of the tape, then remove the top seal
tape and peel back the Mylar until you get past the debonded area (the Mylar
doesn't come off easily). Tape the Mylar out of the way. Remove the old
double sided tape in the affected area. If there's adhesive residue to deal
with, before trying solvents, try using some packing tape or cloth tape like
a "tack strip" - - apply tape to old residue, push down and then pull
straight up. In many cases, sometimes after several applications of the tack
strip, the old adhesive residue will be cleanly removed. Sand, clean,
replace double sided tape as previously noted and as you would if replacing
Mylars.

all the best,

bumper



I have had experience removing tape adhesive using adhesive remover
made by PPG and 3M. I don't have the part number in hand for these,
but you can get information on the web. The adhesive remover does not
contain acetone or MEK and is not nearly as volitile, however it is
flammable. It states that it does not leave a residue. It must have
time to evaporate thoroughly, before any new tape should be applied.
Another possible adhesive remover is a citrus based "goof-off" or
another citrus cleaner. Gel coat is micro porous, but the volitile
fluids like acetone if used very sparingly on a clean rag should not
cause issues with the sub structure. I agree to use caution if you are
not sure, don't use it.

When placing the new tape be sure the surface has no wax or any other
residue. My tapes have held on fine for several years. I used the
TESA tape from W& W's and new mylar with the seal tape over as
described at length above. I used a plastic squeegee to smooth the
pressure on the tape and had no voids in the adhesion. The whole
assembly was then rubbed down and allowed to sit a couple of days
before flying. This allowed the tape to achieve maximum adhesion
charachteristics.

I think the operative condition is clean and dry before applying new
tape and seals.