So true. I'm going to have to start carrying calipers when I am shopping for holiday wrapping paper.

I am also keeping an eye out for a 1.30" diameter tube form, though I'll probably just have to build one up from something like 1 1/4".

https://www.instructables.com/Make-...ft-Paper-Tubes/

Centuri ST-13 and Quest 35mm are definitely not the same. The 35mm tube is a loose slip fit over a BT-55; the ST-13 is too small to do that.

I rolled my own tubes a long time ago using gummed shipping tape as described in an article in Model Rocketry Magazine. I have not seen that tape at the post office or in stores in many years.


Bill

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It is well past time to Drill, Baby, Drill!

If your June, July, August and September was like this, you might just hate summer too...

Please unload your question before you ask it unless you have a concealed harry permit.

: countdown begin cr dup . 1- ?dup 0= until cr ." Launch!" cr ;

Give a man a rocket and he will fly for a day; teach him to build and he will spend the rest of his days sanding...

Interesting. The couple of step by step guides I've read recently mainly use craft paper and glue, laid out in spiral fashion over a mold (mandrel?). It seems key to have a nice smooth surface and patience.

I'm sure the Estes tubes (and the like) are made at some factory in China, but how does a smaller outfit (like the old Carl@Semroc) go about making several hundred (thousand?) tubes of a new or unique size? eRockets definitely seems less inclined to keep some of these Centuri/Enerjet tube sizes in production. Both they and Estes seem to be determined to kill off the ST-13/BT-56 - which of course is the BT/diameter of the Nike-Ram.

I would have thought Aerotech would embrace the rich Enerjet history by producing their own ST-13, ST-20 tubes, at least. Re-engineering just sounds like resizing to use existing parts, to be honest. It reminds me of the Estes (BT-55) Phoenix Bird (another Centuri ST-13) release. That could have been a great model if done right.

Out of curiosity, why the aerospike nozzle? A J650 won't get high enough in altitude before burnout to benefit. The rocket wouldn't even coast to a high enough altitude. Did they do it just because they can?

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I love sanding.

Yup. Gary Rosenfield talked about the aerospike during one of his interviews on The Rocketry Show/Model Rocket Show podcasts - pretty much did it because they can and to make a unique exhaust plume.

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John Scott B.

NAR #102949/L1

Estes, Semroc, and the other U.S. kit makers wre getting their tube from Euclid before they got bought out. According to John Boren, Estes could not find a Chinese tube manufacturer that could make a similar lightweight paper tube to what Estes was buying from Euclid. After Euclid was bought out by Paramount, many of the former Euclid employees retired and tube quality went downhill.

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'Til next time,

Mike Toelle

NAR 31692 L1

SAM 0373

They're not. The tubes are still made in USA.

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-Wolfram v. Kiparski
NAR 28643 - TRA 15520
MTMA Section #606 President

BT-56 is close to ST-13.

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Scott D. Hansen
Ye Olde Rocket Shoppe - Your One Stop BAR Shoppe!
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WOOSH NAR Section #558

I kinda thought BT-56 was the Estes number for the Centuri ST-13 tube. No? At least that is what I had always thought.

Earl

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Earl L. Cagle, Jr.
NAR# 29523
TRA# 962
SAM# 73
Owner/Producer
Point 39 Productions

Rocket-Brained Since 1970

I thought so too. But if you look at the specs at the link below you'll see there is a difference.

https://www.erockets.biz/body-tube-sizes/

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Scott D. Hansen
Ye Olde Rocket Shoppe - Your One Stop BAR Shoppe!
Ye Olde Rocket Plans - OOP Rocket Plans From 38 Companies!
Ye Olde Rocket Forum
WOOSH NAR Section #558