Thursday, July 7, 2011

Semroc IRIS Build Part 3 Fin Taper

The Semroc instructions tell you to sand a taper to the leading edge.
That's a little vague, I wanted this rocket to at least "look" scale.

I found some instructions on JimZ's site for the Estes IRIS kit. You can see it HERE.
A small portion of the instructions are to the right.
It shows a leading edge wedge taper starting at the front band.

On the fin, the taper width looked to be a little over 1/4" or 9/32" wide.

The supplied fins are 3/32" thick. I set them on a flat surface and noticed the root edge wasn't perfectly flat, just a little off.
I carefully sanded the root edge flat, not wanting to take much off as it would change the fit of the tabs and body tube bands.

I went "old school" to sand the taper this time.
This technique goes back to the 1960s to get a clean, sanded line.

Masking tape is layed down at the start of the taper line on both sides. It acts as a "stop" so you won't sand past the desired edge. You do have to be careful though, use too rough a grit and you can sand through the tape edge!

No comments:

Post a Comment