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  #11  
Old 08-15-2016, 09:51 AM
stefanj stefanj is online now
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Thanks Verna! Saving those links to pour over.
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  #12  
Old 08-15-2016, 10:13 AM
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Quote:
Originally Posted by Rocket Babe
The size of the model and choice of engines doesn't matter. It's a simple choice of powering what you build and how you wish to enjoy it. Do you want low & slow, or fast and out of sight? How far do you want to take it, a simple cluster, or staged AND clustered? It all comes down to the builder/flyer.


It does matter. In fact, you verify below.

Quote:
I like to cluster everything. For the Estes 1/100 kit, it flies just fine on a SINGLE D12 under the RIGHT conditions. It also flies well on a 5 engine cluster or as an 11 engine 3 stage. Just determine what you wish to do with a particular kit and make the upgrades.

Clustering is not a problem with most rockets but what you must remember is that anytime you upgrade any rocket you have to upgrade other things as well, i.e. launch equipment and size of field.


Too many people try to do things the model wasn't designed for, and then blame the model for the issue. Any time you add power, you add stresses that weren't designed. You then must reinforce, which adds weight. If you don't choose the proper delay, set the proper CG/CP relationship, strengthen accordingly, and fly in the right conditions, bad things happen.
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  #13  
Old 08-15-2016, 10:16 AM
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Jerry Irvine Jerry Irvine is offline
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I saw a stock (motor mount modified) Estes Comet (BT-55) fly on a 29mm full H successfully and that was white glue construction.

Most rockets are over reinforced.

Jerry
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  #14  
Old 08-15-2016, 10:33 AM
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Well after reading all these testimonials I guess I have nothing to say but good job Estes. You have a great product. Keep up the good work.

Know seriously thanks for all the good information. I like hearing all these successful reports. I have flown my Saturn V on D motors but its always a hold your breath time with the Estes Saturn. With the Alway or Zooch Saturns, they are fun flights. I'm not worried about crashes.

I guess as Roseanne Rosannadanna would say "never mind."
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  #15  
Old 08-15-2016, 10:39 AM
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Quote:
Originally Posted by Jerry Irvine
I saw a stock (motor mount modified) Estes Comet (BT-55) fly on a 29mm full H successfully and that was white glue construction.

Most rockets are over reinforced.

Jerry

The issue with the stock Centuri/Estes Saturn V with bigger motors is the tendency to not stay vertical through ejection with the higher and faster flight profile. The plastic chutes are fine for what it was designed for, but not for bigger motors because it will usually be moving along pretty good at ejection. Odds are the Comet didn't have a stock recovery system.

My point in the original post is that the model is perfectly good for what it is intended, but a person shouldn't blame the model when they start doing things beyond its design. It becomes their fault when it fails at that point. Failure modes may be due to poor motor/delay selection, flying in too much wind, bad CG/CP, which all lead to poor trajectory and high ejection speeds. They then build them like to make up for poor decisions.

I'm not saying don't modify or don't use anything but recommended motors. I'm just saying there's absolutely nothing wrong with a stock Saturn V when used within its design scope.
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  #16  
Old 08-15-2016, 11:00 AM
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luke strawwalker luke strawwalker is offline
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You DO realize of course that Estes DID produce a smaller Saturn V?? The K-39 semi-scale Saturn V from the late 60's-early 70's. Here's a link...

http://www.ninfinger.org/rockets/ca...1/711est40.html

The kit was based on a BT-60 main body tube (for the S-IC and S-II first and second stages respectively) and a BT-50 (IIRC) for the third stage tube above the transition (for the S-IVB stage), which is not *exactly* proportionally correct-- meaning the scale diameter of the S-IVB is "too small" compared to the lower body of the rocket (it needed a fatter upper body tube, but the next size up, BT-55, was too big; I don't know why they didn't use a BT-52 which might have been closer (BT-52 is the size tube for the service module in the regular full-size Saturn V Estes kits IIRC). At any rate, it WAS designed strictly as an "easy build sport flying version" of Saturn V.

Now this leads to a bit of history-- Wes from Dr. Zooch (founder and owner) had saved up his pennies as a lad mowing lawns (like the rest of us) and bought one of the semi-scale Saturn V's to fly. Most of us remember the anticipation of scrimping and saving for a kit, laboriously earning extra money cutting grass in the summer to buy that "special kit" we had burning in our minds, and the excitement when "the day" finally arrived and we got the kit. SO Wes finally his much-anticipated semiscale Saturn V, and eagerly tears into it, and is sadly disappointed-- it kinda looks like a dog, as he goes through the build, and loads it up and flies it, and it flies like a dog. The whole experience was a big letdown, and after SO much hard work and anticipation building in his young mind, earning the money and mailing it off and waiting eagerly by the mailbox for that special package to arrive, only to be let down and depressed by reality when it arrived.

Fast forward a few decades, and Wes is now starting his own model rocket company. His first foray into this new venture-- the "ant-scale" semi-scale Saturn V. Remembering the disappointment in his youth, Wes set out to "perfect" the Estes kit he remembered and make the model that he ANTICIPATED getting... to make a GREAT semi-scale Saturn V kit-- one that looked great (for its size) but would be easier to build than the 1/100 Saturn V (not take a bazillion hours to build) and would fly great. He used the same tube sizes and designed paper wraps for it, designed it to fly with "almost scale size" fins (instead of the fugly clear plastic fins of the Estes version) and added details to make it look more real, all in a kit an eager kid could build with average skills and that wouldn't cost a fortune. Hence, the Dr. Zooch Saturn V, which is basically a COMPLETELY IMPROVED version of the Estes original "sport" Saturn V. Not long after, he did the same treatment to the Saturn IB, releasing it (in fact all versions of the Saturn I save the finless early ones, which he designed and flew but never released as kits).

Now, IMHO what's SADLY LACKING is a BT-80 based version of the Saturn V. NOBODY has EVER offered one, and that's VERY sad, because IMHO it's the "perfect size" for a Saturn V. The 1/100 scale version Estes makes is a VERY impressive kit to be sure, but it's complicated to build and not a terrific flyer, and certainly complicated and expensive enough that they're not flown often-- one has SO much money and time invested in building one that most are probably only flown once or twice and "retired" to be shelf queens for fear of having a dreaded lawn-dart destroy all that time and money. For "sport flying" on a regular basis, the BT-60 Dr. Zooch kit is a TERRIFIC choice-- it's small enough and easy enough and cheap enough to buy and build, and it flies great, so the odds of it getting smashed up are negligible, and even if it did suffer a cato or lawn dart, it's fairly easily and cheaply replaced. One CAN "superdetail" the Zooch Saturn V, but the BT-60/BT-50 tube combination kinda "sticks out like a sore thumb", ie you can TELL VISUALLY that the scale size of the upper body tube does not "match" that of the lower body tube-- it's visibly undersized, but there's really nothing you can do about it. Besides, the whole idea was to make a "cheap" everyday sport flying kit that was easily attainable by the masses, which requires using commonly available "off the shelf" body tubes like the BT-60 and BT-50, not the much more arcane and harder to find BT-52 (which would be closer in size but still "off" from what it should be). Also, the BT-60 kit is pretty small... it's a neat rocket and great flyer, but being SO "small" compared to the prototype (approximately 1/195 scale IIRC) it limits how much detailing you can do, because lots of details are simply "invisible" at that small of a scale, and become near impossible to make and glue onto the rocket.

A Saturn V based on the BT-80 body tube for the lower stages works out to 1/152 scale. Now, the BT-80 tube was invented for the 1/100 Saturn V, which used basically a 3.96 inch diameter (BT-101) size tube for the lower stages, and at 1/100 scale, the upper stage S-IVB would be 2.6 inches (1/100 of the original S-IVB diameter of 260 inches). Hence the BT-80 tube became part of the tube inventory. Many cool "big kits" have come out of that tube size over the years, and in fact, it's one of my favorite size rockets-- big but not TOO big! By lucky happenstance, the BT-80 is *almost* proportionally exactly between the BT-60 and the BT-101. SO, if you build a Saturn V with a BT-80 first and second stage, then you can use a BT-60 for the third stage S-IVB tube and it appears "visually correct" and not undersize. It's not a 100% correct size-- it's actually a LITTLE undersize, because if you divide out the 1.637 tube size of the BT-60 by the original S-IVB size of 260 inches, it comes out to about 1/158 scale, compared to the 1/152 scale of the lower stages-- but basically the BT-60 is only off by 4% undersize, which isn't much. One can give it a wrap or two of printer paper and basically be "spot on" for size-- IOW, nobody's going to know unless they whip out a micrometer and start measuring your rocket. Visually, it LOOKS correct and proportional. Another happy accident is, you're 1/152 scale BT-80 Saturn V will perfectly match the scale of the Dr. Zooch Saturn IB, which uses a BT-60 tube for it's own S-IVB upper stage just like the Saturn V used, so basically you can build the entire Saturn family of I's, IB's, and the V, proportionally to scale with each other! Kinda neat.

Of course, since NOBODY ever decided to offer a BT-80 based Saturn V for whatever mysterious reason, you have to scratchbuild your own. It takes time and effort, but it's rewarding. I'm about 90% finished with my own that I started a few years ago and kinda got sidetracked on, and it's an impressive size model about 2 feet tall or so (I can see it sitting with my collection on top of the bookcase across the room, calling to me to finish it, which I need to get back to sure enough... but that pesky 'real life' gets in the way too much. In fact I did a build thread on it because I was doing a parallel build at the same time of a BT-60 based "Saturn I-F", which was sort of a "what if" vehicle based on the idea that was floated around about building 260 inch twin F-1 engined liquid rocket boosters for the sides of Saturn V, which would have made a terrific monolithic 260 inch first stage for the Saturn IB by putting a 260 inch S-IVB second stage on top (and shutting down one of the F-1's partway through the first stage flight to keep the acceleration within limits, most likely, or powering it by a single F-1 or F-1A engine instead). At any rate, I'm building this rocket alongside the BT-80 Saturn V in the same scale. I've got a build thread of it here...

http://rocketshoppe.com/forums/showthread.php?t=9820

Of course my BT-80 Saturn V isn't the first-- I was inspired to build it by another excellent scratchbuild I saw on another forum years ago.

What's nice about the BT-80 size, is that you can "superdetail" it rather easily, by carving bits of balsa and basswood and bamboo skewers into all the little "bits-n-pieces" like fairings and tunnels and stuff without working in crazy small-sizes like you would have to do on the BT-60 kit. If you want a simpler build, you can also omit some of the detailing or make it "rougher" without it taking too much away from the visual appeal of the finished rocket. Basically, the larger the rocket, the more detail it HAS to have to "look right" and the more precise those details have to be for it to look good. Estes does most of the work for you in this regard with the vacuum wraps and details on the 1/100 kit. The smaller Dr. Zooch Saturn V can "print the details on" as patterns on the paper wrap and it look acceptable for everyday flying, or you can carve and add more of the larger detail bits yourself, and simply omit the smaller detail bits, without it looking "off" simply because of the smaller size. The BT-80 size rocket, being the middle, requires more details be added due to the larger size than the BT-60 size rocket.

ANYWAY, if you're looking for a "sport flying" Saturn V, you really can't beat the BT-60 Zooch kit. The Estes version from back in the day was much inferior.

Later! OL J R
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  #17  
Old 08-15-2016, 11:15 AM
jdbectec jdbectec is offline
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The Estes bt-60 kit did use a bt-52. The Dr Zooch uses a bt-50. Still a nice little kit.I own one of each.I agree a bt-80 or even bt-70 would be a nice size.

Add me too the list of people who have never had a problem with their Centuri kit.I did have a chute failure on an E15-4 flight possibly due to late ejection but the damage was easily repaired.
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  #18  
Old 08-15-2016, 11:43 AM
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The Estes 1/100 Saturn V is a great flier on the 24mm Aerotech engines (SU or RMS) E18, E28/E30, F24, and F32 even when built in STOCK configuration. These engines add little added mass and turn in a decent flight. The only way I'd describe a 1/100 Saturn V flight on a D12 is LACKLUSTER at best, and that's ONLY if there is zero wind. It flies so low you could fly it in an average small supermarket parking lot.
Flying a 1/100 Saturn V on a D12-3 is slightly less thrilling than flying an Astron Alpha on a 1/2A6-2 and far more risky.

As far as the Estes BT-60 based semi-scale K-39 Saturn V, that thing was BY FAR the worst JOKE of a kit ever bagged by Estes. Some things are TURDS that should never make it past pre-production...some good examples of this are the Pontiac Aztek, the Estes K-39, and the USAF/USN/USMC F-35
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  #19  
Old 08-15-2016, 12:49 PM
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Well said Luke Strawwalker. I think you understand what's on my mind. You did a lot better job saying it. THANKS.
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  #20  
Old 08-15-2016, 02:23 PM
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Comrades:

I totally agree that a BT-80 size Saturn V is long overdue. Before Carl passed, I had designed the balsa necessary to make a BT-80/Series 16 Saturn V on the Semroc Nose Cone Designer. Someone else had done something similar as well. This would have had a .997 diameter Service Module (probably Series 9 tubing). We'd still need a capsule.

Certainly do-able within the Semroc catalog. A Skylab would be even easier.

Randy, are you out there?
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