What's in a Name?

 The Thrifty Rocketeer blog continues...

I was skimming a Facebook page recently when a posting caught my eye.  It was basically asking what the term  for a particular style of balsa fin construction is.

What's the term for "making a fin that is comprised of multiple pieces of balsa butted up against each other."

Now, this wasn't anything particularly spectacular.  And part of the reason why it caught my eye was that the fin shape was one that I had recently built.  And so, it was a question that I would have asked as well.

While I can't give you an exact picture, the plan was to make a unique fin shape out out two flat triangles that are glued together to form.... I don't know what... but it makes me think of either a phoenix or perhaps a delta wing fighter...  (I'm talking through my hat here, cause I really don't know how to describe the finished shape.)

For clarity, let's just say that the largest piece of fin is NOT a


sweptback fin that attaches to the body tube via a root edge.  The grain runs not quite perpendicular to the body tube, but enough that it is a strong joint and strong fin.  However, the secondary part of the finished fin assembly nestles in front of the main fin, forming a bit of a stabilizing plane.  It also is attached via the root edge of the second piece, and breaks or covers  the leading edge of the main fin.  So, the second fin, while in the same flat plane as the first,  pierces the airstream before the leading edge of the main fin is struck.

I have to think that this is more a stylistic choice than an actual aerodynamic advantage.

But the point of relating this is the question of what to call this fin assemblage.

Now, a couple of rocketeers scoffed at the question, saying "Who cares?" and "Just build it and launch it."

But I think it's a reasonable question.

How do you describe this "composite fin assembly"?

And, that's what I think it should be called.... "a composite fin".

There doesn't seem to be a consensus in the hobby of what to call this, and I'm certain that the technique has been done before.

The original poster claimed that there was quite a bit of jargon in our hobby, and that it was not always easy to understand how some of the terms came about.

But that's OK.   At least he was asking the question in a public forum, and has yet to get a definitive answer.

So what do you think?

What IS the term for such a fin assembly?

The Thrifty Rocketeer wants to know...

 

Comments

Post a Comment

Popular posts from this blog

The End of the Line

Image
 The Thrifty Rocketeer blog continues... Well, for years, the state of the model rocket industry relied upon plans and patterns that were photocopied or printed out, and then applied to standard sheets of balsa to be cut out. Eventually, the various parts for various sized rockets were packaged in groups or blister packs, and sold at hobby shops across the nation.  The emphasis was on home brew or building a rocket to specifications and plans. Eventually, entire kits were pre-packaged, with all the parts that one would need.  And then, laser cut shapes, fins or parts were already pre-cut, doing away with the need for most of the patterns and tracing. So what happened to all those bags and bister packs of parts of rockets?  That is, a baggie of various nose cones... or connectors... or transitions or more ?   Many of  those packages remain at your local mom and pop hobby store, just waiting for someone to come in and buy some of their pegboard stock.  And the number and frequency of the
Read more

sleeping with the enemy

Image
 The Thrifty Rocketeer blog continues... First thing I did when they put in a Hobby Lobby in my smaller metropolitan town, 40 miles away, was to grab an application to work there.  Now I know what you're thinking... "How could you?  Who would want to work for that conservative corporation?".. as my daughter would say.  And you'd be partially right. I saved the application and took note of the mailing address. Within the first month or so, most of the initial buying frenzy was over, having sold out of some things, but not everything.   But it seemed nothing new was getting restocked. So, I got on my word processor and wrote a letter to the store management, THANKING them for bringing the store to our isolated metro area. I pointed out that many of the items had sold through completely, and how much we had appreciated their stocking rockets. Then I also encouraged them to restock and consider expanding the display, pointing to the fact that as rocketeers grow older, the
Read more

Glassine Tubes

Image
 The Thrifty Rocketeer blog continues... You'll have to excuse me this week, as I slip into a rant. You know what really annoys me? Glassine coated body tubes. You know the stuff... usually low power rockets that have a slick plastic coating over the tube, so that they can make the tube thinner and still have some rigidity left. It may make for a slick, smooth surface to paint, but it is absolute hell when it comes to gluing fins and things onto the body tube....especially at a 90 degree angle. Now, I know what you're thinking....  "That's not so bad.  You can rough it up with a bit of sand paper and break the surface." Right. Except, remember that the paper tube is so thin, it doesn't have a lot of body left to it, and any scratch or abrasion into the tube weakens it. I find this not only annoying, but short-sighted of Estes to be producing these in traditionally popular kits. I've run into this in the Commanche 3, and most recently the Goblin which I bou
Read more