Lonnie Buchanon let me borrow some old Estes parts he found in a Craig's List buy.
Below is a BT-30 tube.
Mark II wrote in YORF:
https://www.rocketshoppe.com/info/Estes_Body_Tube_List_3.1.pdf
"BT-30 is a recreation of the very first body tubes that the fledgling Estes Industries sold in 1960. Yes, these were the legendary tubes that Gleda Estes hand-rolled from mimeograph stencil backing using a slotted aluminum mandrel. BT-30 was used in most of the early Estes Industries kits, including the Scout, Mark, Space Plane, Sky Hook and Sprite (K-1, -2, -3, -8 and -15). The somewhat loose fit of their 18mm motors in it is what makes the tumble recovery-inducing weight shift easier and more controllable in the Scout and Sprite. Other kits that used it were the TK-4 Hornet Mini Brute, the Scout II and Scout III, the Mark II and a number of MRN plans. There is an extended discussion of this tube in John Brohm's Estes Body Tube/Kit Reference v3.1." CLICK HERE
Estes probably had BT-30 tubes made for them when the kit demand got too high to hand roll the tubes.
This one is rolled very tight and clean, I would assume the hand rolled tubes weren't as taut. I can't say for sure as I've never seen a Gleda Estes hand rolled tube in person.
The loose fit reminds me of the old Model Missiles instructions that mention you could use rubber bands wrapped around the motor for a friction fit.
My uncle told me engines used to be mailed in those tubes. So, you could use the mailing tubes as body tubes! I always thought that was a great idea. I'm also 99% sure he had one of the original Estes catalogs in his bookshelf--I used to look through it when I was a kid in the late sixties. But he doesn't know what happened to it.
ReplyDeleteHi Curious,
DeleteThe engine shipping tubes were larger diameter and blue in color. Estes did sell a special nose cone for the mailing tube, #651-BNC-MTD. The mailing tube was 1.002" diameter. The BT-30 tube (shown above) was .767" diameter.