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  #31  
Old 04-01-2008, 02:48 PM
Rocket Doctor Rocket Doctor is offline
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Quote:
Originally Posted by Tom Swift
You got me trying to figure out a way to add adjustable amounts of nose weight to a single NC. After a while I had an idea worked out involving epoxy, all-thread, a spacer tube, a nut, and varying numbers/weights/diameters of washers.

Then I used Google and found an almost identical solution had been done already.
http://www.chmara.com/bt/rocketry/m...gnosecone.shtml


Estes used washers on one of their shuttle kits.
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  #32  
Old 04-01-2008, 03:05 PM
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Quote:
Originally Posted by Rocket Doctor
Estes used washers on one of their shuttle kits.

That be the Estes Shuttle Starter kit.......made of TufLight
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  #33  
Old 04-01-2008, 03:42 PM
GIJoe GIJoe is offline
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Quote:
Originally Posted by Rocket Doctor
You could get additional Baby Bertha nose cones and change the nose weight. I was working on a "D" powered BB and I was going to call it the "Silver Bullet", plenty of nose weight and I'm sure it would had flown like a "bullet" .

I have three prototypes, never finished them off.


If I went with additional nose cones it technically wouldn't be the same rocket. I was just looking for a way to get "A" thru "E" motors in the same airframe. Local club proposed an Alphabet challenge for this years launching. It turned into self paced since I couldn't compete with the Level 3 guys after "I".
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  #34  
Old 04-01-2008, 03:52 PM
Rocket Doctor Rocket Doctor is offline
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Quote:
Originally Posted by GIJoe
If I went with additional nose cones it technically wouldn't be the same rocket. I was just looking for a way to get "A" thru "E" motors in the same airframe. Local club proposed an Alphabet challenge for this years launching. It turned into self paced since I couldn't compete with the Level 3 guys after "I".


So, instead of changing nose cones, and, it might be difficult to make weight changes with the standard Baby beretha nose cone, why don't you just build a fllet of rockets, paint them all a different color to distinguish them from each other and possibly have a drag race. It would be most impressive.

If you have any photos, please post them for all to see.
Best wishes
RD
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  #35  
Old 04-01-2008, 03:58 PM
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Quote:
Originally Posted by GIJoe
Hey Doc just finished my "E" powered Baby Bertha, planned to fly as a Motor Alphabet project. I call it A to E Flat Jam. I flew it on an E in March and it really did scream. In April at our club launch I will fly it on from A to E. The nose weight will make the "A" Flight the hardest. If I get that nailed down the rest will be easy. Great design, I am also planning a 4" diameter version for 38mm motors G-I.

What A were you planning on using?
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  #36  
Old 04-01-2008, 08:02 PM
GIJoe GIJoe is offline
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Probably the A8-3, ideally I would have preferred to a shorter delay. With a little better pre thinking I could've just built motor mounts into a BT-60 coupler and used 4 Quarter "A's". But I can't seem to get two 13mm engines into a 24mm mount. Rocksim claims I will get about 150 feet and stable velocity off the rail. I only have a half ounce of nose weight installed maybe a little more (Used Clay epoxy). If I remember correctly from the Estes Forum you were the man behind the little rocket. Great little flyer, I currently have three of them. The original Baby I built, one my son put together a couple of years ago and now the 24mm. I also have plans for a 4" upscale (38mm). If I get a photo of it I will post it. Right now I am holding off on painting till the weather warms up. So the newest Baby doesn't have any clothes.
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  #37  
Old 04-01-2008, 08:23 PM
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Quote:
Originally Posted by GIJoe
Probably the A8-3, ideally I would have preferred to a shorter delay. With a little better pre thinking I could've just built motor mounts into a BT-60 coupler and used 4 Quarter "A's". But I can't seem to get two 13mm engines into a 24mm mount. Rocksim claims I will get about 150 feet and stable velocity off the rail. I only have a half ounce of nose weight installed maybe a little more (Used Clay epoxy).
You might want to consider the A10-3T. It gives you a bit more of a power spike to get the load moving. But you can compare the two here....

http://nar.org/SandT/pdf/Estes/A8.pdf

http://nar.org/SandT/pdf/Estes/A10T.pdf

You can always use the "insert smaller motor into the larger motor casing" method for motor mount adapters. When simming it, make sure you add the weight of the empty motor case as mass.
Quote:
Originally Posted by GIJoe
If I remember correctly from the Estes Forum you were the man behind the little rocket. Great little flyer, I currently have three of them. The original Baby I built, one my son put together a couple of years ago and now the 24mm. I also have plans for a 4" upscale (38mm). If I get a photo of it I will post it. Right now I am holding off on painting till the weather warms up. So the newest Baby doesn't have any clothes.


No, that would be Ken (Rocket Doctor). But I use it to make Goonies. My favorite is a design from Phred called the Goony Ghost. I painted it with glow-in-the-dark paint. My niece got a kick out of it.
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  #38  
Old 04-01-2008, 08:40 PM
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Mark II Mark II is offline
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Quote:
Originally Posted by GIJoe
If I went with additional nose cones it technically wouldn't be the same rocket. I was just looking for a way to get "A" thru "E" motors in the same airframe. Local club proposed an Alphabet challenge for this years launching. It turned into self paced since I couldn't compete with the Level 3 guys after "I".

That's really splitting hairs , but I guess you are constrained by the rules you were given for the club challenge, right? But still, simply swapping the nose cone for an identical one that just happens to have a different weight doesn't actually change the airframe itself, so... Are there any Pink Book lawyers out there? (...even though this is not a Sporting Code-related issue?)

If you can't change parts, then are you required to use the same chute for the A flight as you would for the E? What do the challenge rules say about the different diameters between the A-C motors and the E? Do you have to use the very same motor mount, with no modifications, additions or subtractions, for all 5 impulse levels?

This must be some challenge, then.

Mark (working on my NAR JD... )

P.S. Don't take my comments above too seriously... I'm just riffing.
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  #39  
Old 04-01-2008, 08:56 PM
Rocket Doctor Rocket Doctor is offline
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Quote:
Originally Posted by barone
You might want to consider the A10-3T. It gives you a bit more of a power spike to get the load moving. But you can compare the two here....

http://nar.org/SandT/pdf/Estes/A8.pdf

http://nar.org/SandT/pdf/Estes/A10T.pdf

You can always use the "insert smaller motor into the larger motor casing" method for motor mount adapters. When simming it, make sure you add the weight of the empty motor case as mass.


No, that would be Ken (Rocket Doctor). But I use it to make Goonies. My favorite is a design from Phred called the Goony Ghost. I painted it with glow-in-the-dark paint. My niece got a kick out of it.


The Baby Bertha is in the top 5 sellers in the Estes line. Gonny's are very popular using the Baby bertha as a basic kit.

If you check out Excelsior Riocketry, Phred has a huge variety of Goony's made from the Baby bertha.
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