What size body tube is this?

[luke strawwalker]

JR, I got BT-58 on the SM as well. BT-52 was used as a "retainer tube" in the D-motor mount as I understand it. The Saturn V also used another oddball tube, the BT-63, which was a slip fit over the BT-60.

Doug

.

Thanks... I try to keep it in the back of my mind what some of those "oddball" sizes are used for, but sometimes I get my spurs tangled up...

Later! OL JR

 

[Odo]

Alright thanks guys!
*Foiled*

Well I can still paint it super shiny silver and call it Chrome Gnome right?
Or that wont fit my tube, will it? :wink:

 

[samb]

Alright thanks guys!
*Foiled*

Well I can still paint it super shiny silver and call it Chrome Gnome right?
Or that wont fit my tube, will it? :wink:

Just another learnin' experience, right ? After a while, you too will have all the tube diameters/maufacturers designations memorized and you'll be impressing your friends and girls at parties ! Just pay attention to the kit specs and be aware of features like boat tails and such. BTW, I do believe that Semroc has a two motor cluster mount for BT-58 but I wont be able to verify this until after work today.

not a cluster, just centering rings for a single 18mm motor in a BT-58: https://www.semroc.com/Store/scripts/prodView.asp?idproduct=2188

 

[Odo]

Just another learnin' experience, right ? After a while, you too will have all the tube diameters/maufacturers designations memorized and you'll be impressing your friends and girls at parties ! Just pay attention to the kit specs and be aware of features like boat tails and such. BTW, I do believe that Semroc has a two motor cluster mount for BT-58 but I wont be able to verify this until after work today.

If so thatd be decent

 

[luke strawwalker]

Noticed that I didn't have BT-58 on the previous list, so I went and checked up... Semroc has produced a number of new tubes, so I added them to the list.

Here's the revised version... tube sizes in order from smallest to largest. Guess I should go check up on other manufacturers and integrate their new offerings into the list... As far as parts go anyway... no sense in listing tubes that you cannot get from parts...
View attachment Tube Size Chart Rev 9-17-13.txt
Later! OL JR

 

[Rich Holmes]

Noticed that I didn't have BT-58 on the previous list, so I went and checked up... Semroc has produced a number of new tubes, so I added them to the list.

Here's the revised version... tube sizes in order from smallest to largest. Guess I should go check up on other manufacturers and integrate their new offerings into the list... As far as parts go anyway... no sense in listing tubes that you cannot get from parts...
View attachment 146198
Later! OL JR

Thanks, I've incorporated that into my rocket scaling spreadsheet available here: https://docs.google.com/spreadsheet/ccc?key=0AhOlGTfCxK5rdF9yczRtN3JxdGtRNjJUSEpxTWQwYXc&usp=sharing. Um, I suppose I should have asked first. If there's a problem I'll remove it. (It's on the second sheet.)

 

[luke strawwalker]

Thanks, I've incorporated that into my rocket scaling spreadsheet available here: https://docs.google.com/spreadsheet/ccc?key=0AhOlGTfCxK5rdF9yczRtN3JxdGtRNjJUSEpxTWQwYXc&usp=sharing. Um, I suppose I should have asked first. If there's a problem I'll remove it. (It's on the second sheet.)

Not a problem... that's why I put it out there... so folks can use it...

I made that list up from a Totally Tubular catalog I printed off a few years ago, and cross-referenced it with printouts of the then-current Estes tube offerings and list of tubes from Semroc as well as those from Quest. I integrated it all so that they are listed from smallest to largest in size, regardless of manufacturer (which is of course indicated at the beginning of each listing) so that it makes it easy to look up the available tubes for scratchbuilding scale models, where the tube size and proportions are critical (especially on rockets that use multiple different stage diameters and therefore need equivalent proportional tubes...)

Later! OL JR

 

[MarkII]

Estes created BT-58 for use in the original K-36/1236 Saturn V and they used it in all subsequent reissues of that kit.

It was also the main body tube in the #0892 Little Joe II (Mini Brute version) and was also used in the #2048 Saturn 1B (both released in 1991).

It was recently used as the main body tube in the #0809 X-Prize Gauchito, released in 2004.

Semroc uses their version of this tube because it is a convenient size for their Deci-scale kits (1/10 scale), such as the #KD-3 Aerobee 150 and #KD-5 Aerobee 300. They also use it in their #KS-8 ARCAS and #KS-12 MX-774 (non-Deci-) scale kits.

 

[MarkII]

A single BT-50 mount will, though you'll need to build your own centring rings.

Semroc doesn't specifically list BT-50-BT-58 centering rings, but they do list an Aerobee 150 ring set. This kit has a 24mm motor mount, and uses ST-9, which is Semroc's beefier version of a 24mm motor tube. So you can use this ring set to create a 24mm motor mount in a BT-58 tube, with Semroc ST-9 as the motor tube. (BT-50 will be too loose.)

https://www.semroc.com/Store/Scripts/prodView.asp?idproduct=2416
https://www.semroc.com/Store/Products/BodyTubes.asp

 

[MarkII]

As for cluster mounts, BT-58 will not accommodate more than one 24mm mount. (See 2xBT-50 in BT-58.pdf)

It will, however, accommodate a pair of 18mm mounts. (2xBT-20 in BT-58.pdf),

but not three of them (3xBT-20 in BT-58.pdf).

View attachment 2xBT-50 in BT-58.pdf

View attachment 2xBT-20 in BT-58.pdf

View attachment 3xBT-20 in BT-58.pdf

 

[MarkII]

You have a lot more clustering options if you step down to 13mm motors.

You can fit a cluster of three in a BT-58 tube, (3xBT-5 in BT-58)


... or four of them, (4xBT-5 in BT-58)


... or even a cluster of 5x13mm (5xBT-5 in BT-58).

View attachment 5xBT-5 in BT-58.pdf

View attachment 3xBT-5 in BT-58.pdf

View attachment 4xBT-5 in BT-58.pdf

 

[mwtoelle]

IIRC (going from memory) BT-58 is the size of the Apollo SM on the Saturn V kit... or is that BT-52...

Anyway, it's kind of a specialty size for a particular kit; most "production" kits don't use that tube size.

BT-52 was used as the Agena stage on the K-28 Thor Agena-B, the S-IVB on the K-39 Semi-Scale Saturn V, the K-59 SPEV, and the Turbo tubes on the 1310 Colonial Viper. As stated elsewhere, BT-52 was also used as a motor hook retainer on several D-powered kits.

 

[MarkII]

EMK2-13-55
and
EMK2-18-60

As stated before, the answers are no and no.

BT-58 has an inner diameter (ID) of 1.498" and an outer diameter (OD) of 1.54".
BT-55 has an inner diameter of 1.283" and an outer diameter of 1.325".
BT-60 has an inner diameter of 1.595" and an outer diameter of 1.637".

So you see, these are three distinctly different tube sizes. BT-55 is smaller than BT-58, and BT-60 is larger than it.

A cluster mount designed for BT-55 will be way too loose and slide around inside BT-58 and one designed for BT-60 will not fit into it at all. Neither one is really amenable to modification to make it fit.

You are much better off getting custom rings made for this project. If you contact Semroc, they may be able to help you. You can also print out the attachments from my last few posts and use them as templates for making your own rings. They will be the correct size when they are printed out, but you must turn off the "Scaling" or "Print To Fit" option in your printer setting when you do so. (In other words, "Print Actual Size" or some equivalent to that.)

FlisKits doesn't use BT-58 in any of their kits, and they don't stock it or any parts for it in their parts section. Semroc is your source for such items.

 

[MarkII]

At the risk of hijacking the thread... I look at those motor mounts and ask, why?

Answer? Lots of fire. Hence, utter coolness.

 

[luke strawwalker]

Thanks for all that information, Mark... Looks like the basis for some cool projects... The one you posted with two 18mm motors in it would make for a cool little Gemini Titan II...

Later! OL JR