E-flite Cap 232 BP ARF - Manual (Page 23)

 2. Slide the tail wheel onto the wire once the
epoxy has fully cured. Use the tail wheel retainer
to keep the wheel in position. A drop of thin CA
on the retainer will secure it to the wire. Make
sure not to get CA into the tail wheel, preventing
it from rotating.
  3. Slide a wheel spacer onto one of the
4-40 x 1/2" machine screws. Slide the screw
into the wheel and thread a 4-40 nut onto
the screw.
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