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Question: Why is glass or carbon better than more traditional materials?

Answer -- Composites are so much more durable… they weigh a bit more, but the materials are incomparable when it comes to strength and longevity. A traditional rocket from paper or phenolic gets a bit “tired” after a few flights. There are many examples of glass or carbon rockets that have had dozens of flight. Finally, don’t let the weight scare you – it is easy to build a rocket that is under optimal mass. Once you use glass, if you are like me you’ll never go back.

Question: Are there kits that I can use to certify L1 and L2, or L2 and L3?

Answer: Absolutely. The Little Dog Dual Deploy is a great L1/L2 combo. For L2 and L3, take a look at the Intimidator 4 or the Competitor 4. It is a great way to “double dip” and save a few bucks.

Question: How much finishing is involved with these kits?

Answer: As much or as little as you like. Most folks leave the carbon unpainted. For glass, the typical finish is a coat of primer (I like “Kilz” in spray cans, from Home Depot or Lowes). For paint, a lot of Krylon gets used. There are no seams to fill and finishing is usually a breeze!

Question: What is the difference between “filament wound” and “convolute wound” glass?

Answer: Think of it this way—filament wound materials are wrapped a bit like a barber pole, at an angle. They are also wrapped in the opposite angle, giving the material an overlapped effect. Filament wound is very strong. Convolute wound is more like the paper on roll of paper towels. The fabric is wrapped in one direction over itself again and again. Like filament winding, convolute is very strong!

Question: So what is better – convolute or filament?

Answer: I’m a huge fan of convolute because it sands, cuts, and drills way cleaner. Filament wound fibers often “splinter” when drilling and they try to re-fill the hole. Convolute wound drills like the material is made out of sugar. The holes are very crisp. If you have to sand an end to make it square, perhaps after a less-than-perfect cut, you can do it easy with convolute. It will take you a while with filament.

Question: Cats or dogs?

Answer: Next question, please.

Question: Tripoli or NAR?

Answer: I belong to Tripoli, but for many years I belonged to both. If you are into EX and you want to go to those launches, go with Tripoli. If you are more of a sport flyer, NAR is a terrific organization.

Question: Is glass or carbon better?

Answer: Complicated answer! Carbon tends to be a bit lighter and it is stronger. That said, I’ve never been able to crumple a convolute glass rocket, and I’ve pushed some to nearly 100 gees. On the other hand, when people see our carbon, they typically are astounded by the gorgeous appearance. Carbon costs more, carbon is prettier, but glass is strong enough – and if you are going to paint it, go with glass.

Question: What is the very best place on earth to fly rockets?

Answer: I’m biased. I like Black Rock a lot, but it is a long ways away. Northern Colorado Rocketry, where I fly, has an extraordinary field.

Question: What is your favorite rocket or kit?

Answer: Whichever one I am working on. (I’m serious). I have as much joy building a 38mm rocket as what I do building an 8” diameter “O” project.

Question: Why “3 Dogs” Rocketry?

Answer: My wife and I rescue Boston Terriers on the side. We have “3 Dogs” now, and we have had for some time. After founding 3 Dogs Rocketry I noticed that this was a common theme in the business… Don’t forget Animal Motor Works, Mad Cow Rocketry, Skunk Works, Polecat Rocketry, etc.

Question: Is there a place for paper and / or phenolic?

Answer: Absolutely. 29mm projects are often built to be as light as possible, and they may not need to be as bulletproof as bigger rockets. I will say that once folks go to glass, they seldom go back. If you’ve ever lost a rocket for a month out on the prairie, you will find out about the durability of glass vs. paper. Also, you can typically get by with much smaller chutes when using composite materials.

Question: What is your highest flight?

Answer: I’m still working on it. Like golf, you have never had “your best shot”. I once got parts to 59,000’. My highest clean recovery was about 35,000’.

Question: EX motors or certified? Which is better?

Answer: It is very cool to “roll your own”, but like you, I have constraints on my time. I’ve worked on some enormous motors, up to a Q. It costs a lot less (once you are set up) but it takes a real commitment. The vast majority of my flights are commercial loads.

Question: Hybrids or solid motors?

Answer: Depends Hybrids have their own set of challenges, but I really like RATT Hybrids, especially the M900. What is not to like about a 13 second burn? Solids are a lot easier to use. For those, I am personally an aficionado of the Loki K350. I am also a huge fan of Cesaroni’s product lineup. See more at HYPERLINK "http://www.lokiresearch.com" www.lokiresearch.com and HYPERLINK "http://www.pro38.com" www.pro38.com

Question: What is the best material for shock cords?

Answer: I like Kevlar. Nylon is great, as long as you don’t let it get cooked with ejection charges.

Question: Are pistons better than Nomex or other material?

Answer: I’m a huge fan of pistons, as long as you are using glass or carbon. If your airframe gets “dinged”, the piston can jam. If you have a nosecone shake loose (see the question on shear pins below) then the ejection charge may very well just blow on by and you will not get your laundry out. A piston will indeed get the chute out – and you will never burn a chute with a piston.

Question: Are shear pins a good idea?

Answer: I’ll let me bias show here. I am a huge advocate of shear pins. I use them on EVERYTHING, for both apogee (drogue) and main charges. For 54mm and below, I use 1/16” polystyrene rods, available from hobby shops. For anything bigger, I use either #4 or #6 screws – depending on the mass and geometry of the project. By the way, this is another area where glass beats the heck out of paper – the glass (or carbon) shears the pins ever so cleanly. Like pistons, I can’t imagine flying without them.

OTHER QUESTIONS?

Answer: Ping me at HYPERLINK "mailto:3dogsrocketry[at]comcast.net" 3dogsrocketry(at)comcast.net and your question will be promptly answered, and it may even make it to these FAQ pages!