12-21-2017, 11:00 AM
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Master Modeler
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Join Date: Jan 2009
Location: Fairbanks, Alaska
Posts: 6,507
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Quote:
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Originally Posted by stefanj
I remember being mystified by references to the BT-40 in Estes literature I read in the early 70s. How could a whole body tube GO AWAY?
Later read all about it in scanned catalogs. The BT-40 was convolute-wound, like the BT-30. There was another, shorter plastic cone available for it, as well as balsa cones, bulkheads, and payload sections.
VERY early catalogs referred to BT-1, BT-2, and BT-3. I don't recall the mapping.
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I first encountered that designation in the Estes plans for the "Maple seed" rocket (it may have had another name; it was similar in general layout and operation to the Flutter-By kit). The model used a BT-40 "outer" section--which had two fins and the glued-in nose cone, plus slots for two other fins--that was sleeve-fitted over the BT-20 (or BT-30) motor mount section, which had the other two fins. I wonder if Estes made those shorter BT-40 plastic nose cones, or if MMI had (for some third kit that never reached production before MMI went out of business). The BT-1, -2, and -3 designations were changed very soon after Estes Industries commenced doing business. |