More than 3FNC - My latest Upscale

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Fore Check

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I wanted something a little different.

This project first started with "Could I?" After seeing a review of a similar (yet smaller) project on EMRR, I decided to have a go.

Then I got to adding up the stuff I wanted from BMS, the nose cone (Sandman), the custom 'chute from STL Rocketry (EdwardW), and the decals (Excelsior Rocketry, or Astronboy) and the question became "Should I?"

Now - before you get all excited - this *is* the LPR forum.....

Anyway, with NSL coming up, I decided I needed something really cool to bring. I think I nailed it.
 
Here's the details:

It's BT70 based, which makes it a 227% upscale from the original.

Sandman made the nose cone (NICE!)

Astronboy did the decals - and they really make the finish product.

The airframe is a shade over 40" long. The "warp pods" are like 14.75" long and made of BT60

The fins and details are made of 1/8 balsa, with the following exceptions: the warp drive pylon wings are 1/8 basswood for additional strength. The rectangular details on the warp pods are 1/32 ply. The rectangular holders for the antenna array are 1/16 basswood. The antenna dish is 1/16 ply.

The dowels are 1/4" spruce, except for 1/8" on the antenna dish.

The discs on the main deck, and the discs on either end of the warp pods, as well as the antenna disc are all laser cut from BMS. The rest of the wood is hand cut, trimmed, and sanded.

Even before paint, this thing was striking. I love all the details built into the look of the thing.

Painting was a real PIA! This is the first rocket I can remember where my main coats got the "runs" and it had to be sanded and and re-painted repeatedly.

After reading Eugene's glowing review of STL Rocketry's T-Cup parachute, I've been working with EdwardW to get one made to bring it back at about 10 fps. Even with a 3 x D cluster, this rocket is draggy and a bit heavy (about 18 oz.) and it isn't going very high anyway. I'd rather chase it than repair it..... :cool:
 
Whoa!! BEAUTIFUL!!

Man, I make so many darn nose cones...I forgot all about that one!

Great suprise! Very impressive! Truly Awesome!

I have a set of JimZ decals for a normal size...it's on the build list.

sandman
 
I like that a whole lot.
Maybe more than I should (he says as he drools all over himself)
That is a great job.:D
 
Originally posted by jflis
oh man, that is **sweet**

can't wait to see it fly! Should go great on D12's and even E9's!

If I ever stick E's in it, they'll hang out the back an inch or more.

I was thinking D12s on that pad where they fly their "delicate" rockets.... :p
 
I know I'm asking a taboo question here, but where the heck did you hide your launch lug? I can't see it anywhere!

WW
 
Martin..... WOW!!!

That is ONE fine model rocket!!

Excellent job!!

Would you email some hi res versions of these photos for the website?

Fred
 
VERY NICE!

That's always been one of my favorites. It brings back memories from when I was a kid.

Can't wait to see it fly at NSL...

John
 
OH MY GOSH!!!!! I can't believe how awesome that rocket is!!!! Wow!!!!


A thing of beauty! I am in awe.


Edward
 
Oustanding - that looks amazing.

Now all we need are flight pics...
 
Originally posted by wwattles
I know I'm asking a taboo question here, but where the heck did you hide your launch lug? I can't see it anywhere!

WW

LOL, the lugs are 1/4" lugs that I got from Apogee (the BT70 tube coupler is from Apogee too - nice!)

Anyway, if you look at the first pic of my son holding the rocket, you'll notice one of the lugs peeking out next to his left hand (the hand on the right as you look at the picture.)

There are two lugs, about 2" long each, nested right up against the inside of that detail dowel on the bottom of the rocket, flush with either end.

In addition to the one I described above, if you look at the pic closesly, you can see the other lug peeking above that dowel at its aft end (right in front of the antenna disc in the pic.)
 
Originally posted by OKTurbo
VERY NICE!

That's always been one of my favorites. It brings back memories from when I was a kid.

Can't wait to see it fly at NSL...

John

I'm looking forward to flying it too - but......

One of the first things my son said after I finished applying the decals and we started taking pics was, "Dad, you might really mess this up if you launch it."

UGH! I'm already having second thoughts.... :kill:
 
The only thing I can claim for the design is the calculations to scale it up, and having contacts like Sandman and Astronboy to make some of the scaled - up components.

It's originally an Estes kit, although the original is quite a bit smaller and based on a BT50 airframe. Kit #1283, produced from 1976 to 1980. Plans available here: https://www.dars.org/jimz/est1283.htm
 
Originally posted by Fore Check
The only thing I can claim for the design is the calculations to scale it up, and having contacts like Sandman and Astronboy to make some of the scaled - up components.

It's originally an Estes kit, although the original is quite a bit smaller and based on a BT50 airframe. Kit #1283, produced from 1976 to 1980. Plans available here: https://www.dars.org/jimz/est1283.htm

If it's structurally the same, I guess you're right. If you made significant changes, I would have entered it anyway.
 
I wish I had a way of modelling where the CP is on the thing. With the winglets, deck, and details, it will be very difficult to swing test.....

I'm guessing that it will be somewhere around the leading edge of the pylons for the warp tubes :)confused: )

Even though they are "capped" at both ends, will the warp tubes themselves provide much for stability?
 
If you have the original kit, then you can measure the CG, which tells you roughly where the CP was, i.e. somewhere behind the CG.

In fact if it's an exact upscale you don't need to know where the CP is, so long as you put the CG in the same place as the original, because CP doesn't move when scaling.
 
Originally posted by hokkyokusei
If you have the original kit, then you can measure the CG, which tells you roughly where the CP was, i.e. somewhere behind the CG.

In fact if it's an exact upscale you don't need to know where the CP is, so long as you put the CG in the same place as the original, because CP doesn't move when scaling.

It's a pretty faithful upscale. However, I don't have a clone or an original.

I'm sure that my CG when prepped for launch will differ by many factors: my 3 x D cluster will be 2.5 oz heavier than scaled up weight of a C6-5; don't know how the 1/4" dowels all over the place match up to the original in scaled up weight; the use of 1/8 balsa for the cap discs on the pylons, with 1/8 light ply centering rings behind them for backup and rigidity vs. simply cardstock on the original; the unknown difference in the scaled-up weight of the original cone and my Sandman upscaled cone; the use of a stuffer tube system; the addition of the tube coupler above the stuffers (not present in the original); the weight difference in my recovery system and the scaled-up weight of the original.
 
You could try the "cut-out" CP method Stine mentions in the Handbook. Even though it's an asymmetric design, do a silhouette of the smallest area possible and see where the cut out balances.

BTW, you did an excellent job on your Atlantis. Find a BIG field to fly that from!
 
Originally posted by Fore Check
It's a pretty faithful upscale. However, I don't have a clone or an original.

I'm sure that my CG when prepped for launch will differ by many factors:

I'm sure it will, which is why you might need to correct it back to where it should be. Are there any plans on Jimz that will tell you where the CG is on the original?
 
Sorry, that's confusing!

I meant to say "do the plans on jimz tell you where the CG should be?"
 
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