F.S.I. Fin Alignment Fixture
I remember seeing it in the FSI catalog but never saw one up close.
It looks a little rough, even the FSI stamp didn't fit on the base.
The white squares are pieces of cardstock glued to clothes pins.
The instructions (below) show clothespins clipped over the fins and the vertical alignment plates. The flat card stock pieces prevent the fin from getting dents from the clothespins.
Well, that's what I thought. The card stock would have to be slipped under the open jaws of the clothespins. Gluing the pieces to the outside of the clothespins does nothing!
This device worked pretty well with three finned models, most all the FSI kits had three fins.There was a problem though.
Notice the two different diameter central spindles.
All FSI kits (at the time) were designed for their 21mm diameter black powder engines.
Most FSI kits had 23mm and 30mm body tubes.
This Fin Alignment Fixture only worked with FSI kits.
Later, FSI started making 18mm engines.
The FSI instructions I've seen had hand written copy.
Here's how it looked in the 1977 FSI catalog.
To see it and the rest of the catalog -
CLICK HERE
Speaking of wooden clothespins, turning them inside-out and backwards changes their clamping characteristics -- increased reach, and due to change in leverage, they're less apt to crush balsawood (you still want to put cardboard plates to spread the clamping force over wider area to reduce possibility of crushing).
ReplyDeletehttp://photo-otaku.com/assisting-tools-mighty-clothespin/
Thanks Naoto,
DeleteI looked the website. I never occurred to me to flip over the clothespins. Great idea and probably an upcoming blog post!