Has anybody worked out a simple upscale ratios grid?

Here's what I'm trying to figure out:

If the original modroc was based on a BT-20, and you have a chunk of BT-60...what's the upscale percentage so you can figure out (quickly) how much balsa / what size NC / etc. you'd need for the upscale?

If this hasn't already been posted somewhere, I'll work something up...just thought it would save a little time if I didn't need to reinvent the wheel.

__________________
Dean Fox
NAR #53946SR

---- "Wherever you go, there you are"

Dean

I'm not sure if this is what you are looking for .....

Scott posted a "scale data chart" spreadsheet with the building tips here at Ye Olde Rocket Shoppe:

http://www.rocketshoppe.com/tips.htm

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Steve Naquin
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All you need to do is divide the new body tube size by the old body tube size for the upscale / dowscale ratio.

1.637 (BT-60) / .736 (BT-20) = 2.22418 222% upscale.

EDIT: The Body Tube Ratio spreadsheet from the previous post works also but for me, it's easier to calculate the ratio rather than go find the spreadsheet and look it up.

That's all there is to that!

It also works the same for a downscale. BT 20 (0.736) /BT-60 (1.637) = 0.4496 or 45%

Math is our friend!

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"I'm a sandman. I've never killed anyone. I terminate runners when their time is up." Logan from "Logan's Run"

http://sandmandecals.com/

Thanks for the replies, all.

(reminds me of the Dilbert cartoon where the boss asks Dilbert a question, and Dilbert replies with "All you need to do is divide the circumference of the table by the radius of the room" (or some such) and the boss just looks at him and says, "Don't get all mathy on me!")

Seriously...what I was looking for was closest to the "Body Tube Ratio Chart", but that chart is missing the "smaller" BT- sized tubes...but I'll just go ahead and do the calcs to make my own sheet for them.

As always, thanks!

__________________
Dean Fox
NAR #53946SR

---- "Wherever you go, there you are"

Dean,

I'm confused by you last statement..."smaller body tubes"...???

Is there something smaller than a BT-2?

A launch lug maybe?

The chart seems OK to me but then again I always do the math anyway...that's just me.

Besides, I need the math thing for the fins and nose cones so I can scale them up or down.

__________________
"I'm a sandman. I've never killed anyone. I terminate runners when their time is up." Logan from "Logan's Run"

http://sandmandecals.com/

Maybe it's a terminology thing: Is a T-2 the same as a BT-2?

I was taking the chart's creator literally...he states that a "T" prefix is a Totally Tubular-produced tube, but a "BT" prefix indicates an Estes-produced tube. So there's no diff?

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Dean Fox
NAR #53946SR

---- "Wherever you go, there you are"

Maybe it's a terminology thing: Is a T-2 the same as a BT-2?

Yes, Jim Fackert (Totally Tubular) made up the list you are referring to. The "T" designation is his own and yes a BT-5 is the same as a T-5.

His designation system using the "T" also works with some odd sizes (Like the T-.700) and some of the Centuri sizes.

When Jim started this system nobody else was making any other distinction on tube sizes so he came up with the "T" thing.

Did I explain that right??? ..hope so..

Well there isn't an industry standard for anything smaller than a BT-3 (which was the escape motor on the 1/70th Apollo Capsule).

The BT-2 (0.246) and BT-2+ (0.281) are Micro Maxx sizes.

His selection is great for doing scale stuff....if you aren't in a big hurry!

__________________
"I'm a sandman. I've never killed anyone. I terminate runners when their time is up." Logan from "Logan's Run"

http://sandmandecals.com/

Like this one that I tried to send you, but maybe my e-mail filter "zapped" any of your incoming e-mails?

I had to "ZIP" the file since the forum didn't recognize ".xlr" as an accepted format.
It's rough, and probably Not Ready for Prime Time, but here you go anyway.


Cheers, buddy!

Attached Files

SemrocEstes_BodyTubeRatios.zip (9.1 KB, 122 views)

__________________
Jay Goemmer
"Centuri Guy"/"Tau Zero"
YORF Member 28
Semroc SAM #0029
NAR 86131


"I think about organizing things all the time. Never seems to happen. I find something that piques my interest and I'm off on a quest. Or a Centuri. "

--Bill Eichelberger, 02/22/2022


“Centuri fret buzz in an updated form.”
Bill “Wallyum” Eichelberger re: Estes Flutter-By
03 Sept 2014

You da man, Jay! That's exactly the format I was looking for.

Y'know, at the rate email filters are killing legit email, the day's just around the corner when email will be useless.

__________________
Dean Fox
NAR #53946SR

---- "Wherever you go, there you are"