Estes Scrambler Body Tube Question

In an incredible bit of serendipity, I managed to get the parts for a number of Estes Scramblers (Kit # 2072) The hobby store owner had them sitting in his
back room. Apparently they were ordered and paid for over 5 years ago and the purchaser never came by to pick them up. Would I be interested? (Is water wet? Does fire burn?) He gave me a box. It has 9 egg cones, 8 body tubes, and about 6 short tubes for the egg cones. I also have the fin stock, several 18mm motor mounts, and a few parachutes. So here is my questions. Are the body tunes BT-56? (I tried a BT-55 and the cone does not fit.) Also, what size is the short tube for the egg cone? Is it a BT-70? I'm planning on introducing my nephew and his cub scout den to rocketry with these rockets. I'm sure in time his parents will forgive me.
Bill Sullivan
"Initiating the 'getting the hell out of here' maneuver"
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Parts were inherited from Centuri.
Main body tube of carrier rocket was Centuri ST-13 which is Estes BT-56.
IIRC, the payload section tube was Centuri ST-20. i don't know the Estes equivalent.
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shreadvector wrote:

Thanks a bunch. Now I know where to get extra parts. Semroc.
Bill Sullivan
"Initiating the 'getting the hell out of here' maneuver"
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Here is the origin:
http://www.dars.org/jimz/ke-4.htm
later versions for smaller motors from Centuri, and then Estes.
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On 31 May 2005 11:14:54 -0700, "shreadvector"

Wasn't ST-20 equivalent to a "thicker-walled" BT-20? Or am I thinking of something else?
- Rick "Not entirely helpful, I'm afraid" Dickinson
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Common point of confusion.
ST-7 was thicker walled BT-20 (actually, slightly larger ID and thicker wall).
Centuri Tubes used a numbering system loosly based upon their diameter in inches.
7 was around .7 inches
10 was close to 1 inch
13 was close to 1.3 inches
16 was close to 1.6 inches
20 was close to 2 inches
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Rick Dickinson wrote:

I always thought the BT-30 was the thicker stock of BT-20. I know it was used on the Astron Skyhook.
Ted Novak TRA#5512 IEAS#75
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Close to truth. Originally there was a small tube, about the size of BT-5, and a larger one which was later called BT-40. These corresponded to two sizes of motors made originally by (or rather, for) Orville Carlisle and G. Harry Stine. I had a few of the 3/4" (Brown Rock-A-Chute) ones for a while in the early 1970's. Both of these tubes were parallel-wound, hard white tubes, but the smaller one was long gone before I flew my first rocket in 1964. In 1964, the BT-40 was still in the catalog along with several parts to fit it, but no kits. A BT-20 motor tube would telescope inside it, but the Rock-A-Chute motors fit without an adapter.
When Vern Estes sized down the motor to .690" diameter, the current "18 x 70 mm" size ( about 1958? ), he also introduced a slightly smaller, thinner, lighter body tube, still parallel-wound like BT-40. This was BT-30 and it was used in the Scout, Sky Hook, Mark, and several other early kits. It was gradually replaced by the spiral-wound BT-20.
Centuri ST-20 was quite different, though: the 20 was the diameter in tenths of an inch.
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Estes designations were merely relative (i.e. BT5 < BT10 < BT20 < BT50, etc) whereas the Centuri designations were based on the actual dimensions (ST-7 was roughly .7", ST8 was roughly .8", ST13 was roughly 1.3", and ST20 was roughly 2.0". Each was actually around .05" larger)
wrote:

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BT-56 it is. Actually Centuri ST-13, available from Totally Tubular and probably BMS.

Nope. Centuri ST-20, just a tad smaller than BT-70. SHould also be available from TT, and maybe BMS.
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I had an Estes Astron Scrambler in 1969, and it was an entirely different kit from what you describe. It had an egg-shaped balsa nose cone, a clear plastic PST-65 payload tube, a balsa TA-6065 adapter, a BT-60 main body tube, and a cluster of three 18mm motors. The three fins were long and swept back at about 45 degrees.
Prior to that I had an Astron Ranger, the first rocket I lofted an egg in. Only a very small egg fits in a BT-60, and I suspect that the Astron Scrambler grew from so many people commenting on that.
Clustering was an adventure back when igniters were made by wrapping nichrome wire around the tip of a ball-point pen to create a tiny heating coil.
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