Buttons or Lugs?

KCAR has a small rail, and you're welcome to join us any time. Not sure where you live, but there is an active club in Columbia Missouri, too.

Rick NAR 85751 Kansas City Association of Rocketry -

Thanks for the reply and the feedback. I'm in Springfield, btw.

Any particular place that you regularly get the buttons? I've never used them before--are they sized in any way (particularly to fit KCAR's rail)?

Do you live near the Simpsons? 8-)

"Tanstaafl32" wrote in news: snipped-for-privacy@i39g2000cwa.googlegroups.com:

I guess someone should mention that the rail is a standard aluminum extrusion available from McMaster-Carr,in varying lengths. (If you want to make your own launch pad.)

Springfield, huh? Your closest launch site is probably Tripoli Prefecture #101 (Tripoli Mo-Kan)High Power Rocketry for Southeast Kansas & Southwest Missouri. Their launch site is over by Pittsburg, KS.

Rick

tanstaafl - a Heinlein reference?

One option I've not seen mentioned is Buttons AND lugs. (a bit more drag, but also a bit more flexible)

If you're using club pads, there might be times you can get rail sooner than a rod, but for your private launches, you might only have a rod.for example.

I'll tell you though, that once I started using rails, I never used anything else on birds larger than BP size, and added buttons to those birds that had LL's.

With a rail, there will be absolutely no "rod whip".

Long ago I learned to NEVER believe absolutes. OK, almost never :-)

A rail is a heck of a lot stiffer than a rod. There will be a lot less whip using a rail than a rod. But unless both the rail and the pad it's mounted in are infinitely stiff and strong, there can still be some. You might not be able to detect it, but it WILL be there.

It's true of skyscrapers as well. The John Hancock building here in The Windy City sways as much as 18" at the top.

Next door. :)

Naturally, with the whole Springfield thing.

...and there was me thinking it might stand for:

There Aint No Such Thing As A Free LAUNCH

Gravity is a harsh mistress, after all ;)

Cheers,

Greebo

P.S. I've got most of the RAH books, but what's the Spr> Rick wrote:

The problem with buttons, is that there are several rail sizes. You gotta have the buttons to fit. In our club, we have many different size rails and rods, just pick your on the way out to the pad.

Can't say I've seen a 3/8" or 1/2" rod whip much.

It absolutely stands for No Free Lunch.

However, RAH was born about 2 hours north in Butler. When Starman Jones ran away from home, he actually travelled towards Springfield - which was a major railroad hub back in the 40's and 50's. I used to hang around with a girl that was supposedly a grand niece or some such.

Odd thing, the fellow in the next cube is from Butler and knows all about RAH even though he claims to have never fully read ANY book, sci-fi or otherwise.

Now then, your quote seem to be a combination of the title of the TANSTAAFL book (The Moon is a Harsh Mistress) and a line from the best cartoon ever made, The Tick. Kudos!

Greebo wrote:

Do you live on Evergreen Tarrace by any chance?