Thursday, September 18, 2014

Estes Black Brant III, Part 7, Tube Fill, Fin Primer

This replacement BMS BT-50 had the tightest seams I'd seen in a while.
Normally I'll run a mechanical pencil down the seam rut so it's easier to see when applying CWF.
The pencil kept slipping out of the seam.
Still, if you can feel it with a fingernail it gets CWF and primer.

The front and back ends of the tube got a wipe of CA glue.
You can use your fingers as a depth gauge as you go around the edge.

The fins were shot with primer/filler and sanded.

On the left you can still see the sanded fin taper.
I sand the tapers first trying to keep the sandpaper away from the high ridges.

After sanding the primer still shows on the high points of the tapers.

As thin as the sprayed primer coat is, what's left after sanding helps define the sharpness of the taper edge.


  1. Do you use filler primer in place of CWF? I've heard it will do the job.

  2. No, I use both.
    The CWF is applied first, then sand to surface.
    That fills 90% of the seams.
    Primer/filler follows and fills in anything that remains.