Great Planes PT-40 MkII Kit - GPMA0118 - Manual (Page 7)

• There are two types of screws used in this kit:
Sheet metal screws are designated by a number and
a length.
For example #4 x 5/8".
Machine screws are designated by a number (threads per
inch) and a length.
For example 4-40 x 3/4".
• When you see the term “test fit” in the instructions, it
means you should first position the part on the assembly
without using any glue, then slightly modify or “custom fit”
the part as necessary for the best fit.
• Whenever just “epoxy” is specified you may use either
30-minute epoxy or 6-minute epoxy. When 30-minute epoxy
is specified it is highly recommended that you use only
30-minute epoxy because you will need either the working
time and/or the additional strength.
Fuse = Fuselage
Stab = Horizontal stabilizer
Fin = Vertical fin
LE = Leading edge (front)
TE = Trailing edge (rear)
LG = Landing gear
Ply = Plywood
" = Inches
Cyanoacrylate or CA glue has changed the way models
are built more than any other advance in modeling
technology. In the good ol' days, model cement like
Ambroid, Duco, Comet and Sigment were the glues of
choice. They all had a strong odor that could cause
dizziness, dried slowly (compared to CA) and became
brittle with age. CA, on the other hand, is stronger, works
almost instantly and is bottled in three different viscosities
(thicknesses). CA is used for most glue joints, except where
epoxy is specified. CA does emit rather strong fumes (some
say it's like tear gas) as it cures, so rule number one is to
work in a well ventilated area.
All CA glues work best if the joints are smooth and the
parts fit well.
Thin CA is also known as plain CA.
This is the instant variety, used for
most initial assembly and tack gluing.
Thin CA is usually “wicked” into a
tightly fitting joint by putting a few
drops on the seam, then holding the
par ts together while the CA
penetrates and bonds the par ts.
When gluing plywood or hardwood, a
mist of accelerator (see page 8) will
help the CA work a little better.
CA+ is also known as medium or
gap filling CA. CA+ is used for
surface gluing, filling small gaps
between poorly matched parts and
for general purpose applications. It
cures slower than thin CA, allowing
you to apply a bead to two or three
parts before assembly. Also, because
it cures slower than thin CA, it
penetrates the wood for a stronger
bond. Curing time without accelerator
is 20 - 30 seconds.
CA- or thick CA is used when extra
positioning time is needed. CA- is a
great gap filler and is also used to
make fillets when a little extra
strength is required. Curing time is
about 1 - 2 minutes.
The What and How of Adhesives
Types of Wood
Common Abbreviations Used in this
Manual and on the Plans
Building Notes
7
Balsa Basswood Plywood
#4 x 5/8" Sheet Metal Screw
4-40 x 3/4" Socket Head Cap Screw