Tuesday, July 12, 2011

Semroc IRIS Build Part 10 Primer Band Mask

In this step, the tube will be marked for masking before spraying the primer.
There will be a strip mask for both bands and the fin root edges.
The bands will be glued on after the primer is sprayed and sanded. Later on, the fins will be glued on after they are painted red.
The fins are even with the back end of the body tube.

The rear of the wrap recess is marked with a pencil. Make this an accurate mark, it will effect how well the fin lines up with the end of the body tube later on. I double checked the position with a wrap of scrap paper.

The fin line (where the lower wrap would start) was extended up to the top of the body tube to mark the start point of the upper wrap band.

Notice the pencil line is not as wide as the band. This is the line for the width of the masking tape.

Primer will be sprayed before the bands are glued around the tube.

On the fins side, the wrap line was penciled around the tube.

Note on the upper leading edge of the fin there is another line. This is slightly below the taper in the fin. That's as high as the masking tape strip will go, not above the widest root edge of the fin.

This is a pretty smart way to make a double stepped wrap. The wide end is started first, the narrow band wraps over the top.


  1. I must admit I did not follow this. Maybe it will become clear in later posts.

  2. Hi Jeff,
    Sorry, this was a different mask and hard to explain.
    I am trying to mask for the bands and fin tabs. The fins will be glued on after painting red and after the black/white separations are done on the main airframe.
    I had to fill the body tube seams and prime before gluing on the bands.
    I'm also trying to keep the root edge gluing lines as bare tube for best adhesion.