Figure 3. After
edges with a
hot iron, shrink
the patch with
a heat gun.
ink marks with
your model will
be nearly as
good as new.
Figure 2. With
the patch lying
flat and upside
in the overlap
it will need to
stick to the
it to the edges
for a good,
Thinner may help make the contact
glue more spreadable. At this point,
it’s also a good idea to put some glue
on the rib surfaces, TE, and balsa
around the engine mount if you’re
covering around that region. If you’re
not using the water-based cement,
don’t allow the cement to touch any
Carefully flip the patch back over
and lay it on the model, using your
marks as a guide. For this step, it’s
helpful if someone can lend a hand to
keep the covering tight and get it laid
down straight the first time. It’s easier
if you aren’t trying to take photos in
the middle of doing it.
Stick down the edges with a sealing
iron and use a heat gun to shrink it
tight. A little rubbing alcohol on paper
towel will get those alignment marks
off, and the finished product is ready
to fly (see Figure 3).
Every time you cover an airplane or
take an iron/heat gun to it, there’s a
chance that it will become warped. To
minimize warping, I try to frequently
flip the model to keep even tension
on both sides. Before heading out to
the field, make sure that the wing
is straight. When you test a patched
model, make sure it is flying flat.
During level flight, can you see the
top or bottom of the wing? If you flip
it inverted, do you see the opposite
side, the same side, or nothing at all?
If you see opposite sides of the wing
level and inverted, then you have a
warp. If you can’t see any twists when
you hold the model in your hand,
then use this rule of thumb: if you see
the top of the wing when flying level,
bend the TE of the outboard wing up.
If you see the top or bottom of the
outboard wing during both level and
inverted flight, then you should adjust
your tip weight accordingly.
When those patched models are flying
straight, they should be ready to chase
some streamers. Happy flying.
Miniature Aircraft Combat Association (MACA)
131 Model Aviation MAY 2014