What to do with a bunch of BT-51 or BT-52 tubing?

Hi folks,

I don't build so much anymore, but I have a few projects I want to work on and I set about cleaning up my supplies. Everything got moved around in a basement flood a bit more than a year ago.

I sorted out my various body tubes, and found I had 4 lengths of an unusual body tube diameter, a bit bigger than BT50. Got out my calipers; the outside is ~1.005" and the wall thickness is just over 0.020; given the variability in my measurements this means it is probably BT51, maybe BT52. It's too big to use BT50 / Series 9 nose cones for sure, tried one and it was a hard pass. The cone went in past the shoulder.

I went through a phase some years back where I ordered some "odd sizes" (not odd, just not Estes standard) in prep for some scale projects that never happened. I recall one order had some damaged tubes and was replaced; hence I have four of these nearly 3 feet long tube that are mostly good with two of them having a crimp at some point along the length. I've got no nosecones for them and even eRockets doesn't carry many cones in this oddball size.

Bottom line, not sure what to do. Any ideas?

Could they be SEMROC copies of the Centuri ST-10? They are 1.04" OD and 0.020" thickness? eRockets carries ST-10 and corresponding cones.

BT51 was used for the tube tanks for KOSROX'S Sat 1b and fits nicely over the bt50 tubes

Massrokit said:

BT51 was used for the tube tanks for KOSROX'S Sat 1b and fits nicely over the bt50 tubes

Click to expand...

Funny, I was just looking at the .pdf of the 1/70 Kosrox Sat 1B yesterday.
You can use them to also do a clone of either the 1/70 Estes Sat 1B (K-29) or the Semroc Sat 1B:
https://www.spacemodeling.org/jimz/estes/k-29.pdf
https://www.semroc.com/Documents/pdf/Saturn 1B.pdf
(The BT-63 tube is practically identical in diameter to a paper towel tube).
The Apollo capsule unit might still be available from eRockets.
If not you can use the Apogee 1/70 capsule. The Apogee unit is more expensive but much easier to assemble with greater detail. They also sell generic vacformed corrugated wraps.

Or you can use short segments of the BT-52 as engine hook retainers on 24mm motor mounts.
Or outside couplers for BT-50 tubes.
Maybe punch a hole and use as staging couplers like the Centuri Passport staging method?
You are only limited by your imagination!

More info, from John Brohm's Estes body tube reference list:
"BT-52 was used as an airframe part in only a handful of kits, as follows:
- K-28: Thor-Agena B (BT-52S Agena upper stage)
- K-39/1239: Semi-Scale Saturn V (BT-52AG S-IVB section)
- K-59: SPEV (BT-52AG payload section)
- 1310: Colonial Viper (BT-52S outboard engine sections)
Thereafter, BT-52 found use as an engine hook retainer sleeve (its ID being a slip fit over BT-50) and it is in this capacity that most present day modelers will have seen the type."

Tube fins. (Put a pair on each side of a standard size body tube with standard nose cone, BT-20 or BT-50.)

Couplers for BT-50s. You will need to cut out a lengthwise segment so they will roll up and fit, but will work.

Engine blocks for BT-50s, again same as above. MUCH lighter than using centering rings for engine blocks.

If a BT-50 slides easily inside these tubes, can have some fun designs with telescoping rockets, such as gliders.

Also would work as the body tube of hexagonal or other polygonal rockets such as @neil_w ‘S pencil rocket. Use balsa or card stock for the outside shape. Custom card stock nose cones are easy to make as hexagonal or other polygonal “pyramids”. These are the standard for my helicopter and air brake recovery rockets (4 sided) as well as my MIRV project rockets (will have three 4-sided sustainers, internal angles 60-120-60-120 that fit together at launch.)

Or roll your own conical nose cones, sort of like WAC Corporal.

Thanks guys. Indeed the BT51/ST10 (or whatever it is)is slip fit OVER the BT-50 tubes; so I could use BT50 nose cones in situations using a piece of BT50 inside the 51 in cases where the transition wouldn't look odd. Great other ideas like tube fins and the like. It's probably ST10; my chart with sizes has an error (OD of 1.400 instead of correct 1.040 inches) so I didn't consider this. Indeed eRockets has a bunch of cones; I'll probably grab a couple...