In Praise of LPR

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What is a spool?

Just what it sounds like, a flying spool:
loc_coolspool02.jpg


the_spool_bell_03.jpg
 
I would love to understand the aerodynamic principles that allow a spool rocket to be stable and fly.

A cone rocket, OK, I kind of get that. All the air has to move, in roughly equal amounts along all paths, down the continuous cone shape. But a spool?
 
I am so sorry. What is a spool?

spool.jpg

This is my newest spool rocket. It's built rather than using a "found" spool like my last one. It has a main body made from a piece of BT80, and end disks made from 1/8" ply. It has a 24mm motor mount with a "long" clip. This one has a parachute for recovery, but smaller/lighter spools (ie. 18mm) can get by with tumble recovery. It has a LOT of drag. When the motor burns out, it pretty much stops flying, so short delays are needed.
 
“Model rocketry” is definitely a “Big Tent.” There is room for just about everything safe, from MicroMaxx to High Power.

the boundary between Low Power and Mid Power is somewhat artificial, somebody said E thru G would be mid power, no regulation, except I think they recommend a 30 foot cord from button to pad and a larger pad and rod (or even better, a rail.)

I have seen some tremendous skill and creativity in High Power, to be sure, although the main thrust (pun intended) in high power seems to be bigger, faster, , or higher, staging, all of which are cool. Also cameras are common and I think add to enjoying the flight AFTERWARD. Disadvantages of high power are cost, and convenience of launch site availability and scheduling (due to need for waivers.). I think High Power builders are less likely to go with designs “outside the box”, perhaps because such designs are a bit more risky to go catywampus. Skywriting with a low power bird is eye catching, frowned upon, but usually merely entertaining. The same with High Power often requires a change of underwear. The cost of replacing a destroyed rocket due to fecal turbine interaction is also dramatically different between the two, as with High Power you potentially lose all the electronics and the case. So perhaps more reluctance to build something with a less than conventional flight profile. Also, not always true but most commonly a builder has put much more of his or her time into a high power build than low power build. A good exception may be @Funkworks
https://www.rocketryforum.com/threads/a-rocket-for-a-smurf.159959/page-11#post-2160863
Which is currently at 13 months and counting, although I think we are getting close! That one is mid power.

MicroMaxx has convenience of extremely low cost, you can often launch from your back yard, so nothing beats it for convenience of launch sites. About the only thing I haven’t seen yet in MicroMaxx is camera Rockets and remote controlled gliders, although they may come eventually. MicroMaxx likely requires more physical dexterity in dealing with itty bitty parts.

Low power is also extremely cheap compared to high power, and the variety is across the board. To me, the classic three fins and a nose cone gets pretty boring early on, but you can branch out into helicopter, AirBrakes, gliders (free flight and radio controlled), cameras, staging, scale models, fantasy style models, saucers, Odd Rocs (flying potatoes, hot dogs, cola cans, tape worms, Cranes, Skeletons, outhouses, the sky is literally the limit.). There is also competition for MicroMaxx and Low Power. Note all of these (except competition) CAN be done with High Power, and many of them HAVE been done, but much less commonly. Also launch sites, while still challenging especially in drought conditions, still far much more readily available than high power.

disadvantages of low power: less shock and awe compare to high power. Also lower altitude due to two factors, first the motors are obviously smaller. second (although this too is in process of changing), tracking and recovering a small rocket that goes out of sight and site (likely if it goes over 2 thousand feet) without electronic trackers is sketchy, although FlightSketch may have a tracker that can fit a low power rocket soon, and Jolly Logic has dual deploy for larger low power rockets and I have heard rumors may have something for smaller rockets as well.

mid power? Pretty much the same as low power to me, but a bit more shock and awe, as they are larger, and can carry payloads Such as larger cameras, CAN fly higher (although motor choices can be made to keep them in range on smaller field if wanted) and are much more electronics friendly if that’s (one of) your thing(s). Cost is a bit more, and you need to build a bit stronger.

yes, this diatribe does have a point. There are only two key rules in model,rocketry.

1. Be safe

2. have fun.

doesn’t matter if your rocket weighs a fraction of an ounce and only goes up 50 feet or weighs a few hundred pounds and approaches the Karman Line, it’s YOUR rocket, and as long as those two rules are applied, don’t worry about what anyone else thinks!
 
“Model rocketry” is definitely a “Big Tent.” There is room for just about everything safe, from MicroMaxx to High Power.

the boundary between Low Power and Mid Power is somewhat artificial, somebody said E thru G would be mid power, no regulation, except I think they recommend a 30 foot cord from button to pad and a larger pad and rod (or even better, a rail.)

I have seen some tremendous skill and creativity in High Power, to be sure, although the main thrust (pun intended) in high power seems to be bigger, faster, , or higher, staging, all of which are cool. Also cameras are common and I think add to enjoying the flight AFTERWARD. Disadvantages of high power are cost, and convenience of launch site availability and scheduling (due to need for waivers.). I think High Power builders are less likely to go with designs “outside the box”, perhaps because such designs are a bit more risky to go catywampus. Skywriting with a low power bird is eye catching, frowned upon, but usually merely entertaining. The same with High Power often requires a change of underwear. The cost of replacing a destroyed rocket due to fecal turbine interaction is also dramatically different between the two, as with High Power you potentially lose all the electronics and the case. So perhaps more reluctance to build something with a less than conventional flight profile. Also, not always true but most commonly a builder has put much more of his or her time into a high power build than low power build. A good exception may be @Funkworks
https://www.rocketryforum.com/threads/a-rocket-for-a-smurf.159959/page-11#post-2160863
Which is currently at 13 months and counting, although I think we are getting close! That one is mid power.

MicroMaxx has convenience of extremely low cost, you can often launch from your back yard, so nothing beats it for convenience of launch sites. About the only thing I haven’t seen yet in MicroMaxx is camera Rockets and remote controlled gliders, although they may come eventually. MicroMaxx likely requires more physical dexterity in dealing with itty bitty parts.

Low power is also extremely cheap compared to high power, and the variety is across the board. To me, the classic three fins and a nose cone gets pretty boring early on, but you can branch out into helicopter, AirBrakes, gliders (free flight and radio controlled), cameras, staging, scale models, fantasy style models, saucers, Odd Rocs (flying potatoes, hot dogs, cola cans, tape worms, Cranes, Skeletons, outhouses, the sky is literally the limit.). There is also competition for MicroMaxx and Low Power. Note all of these (except competition) CAN be done with High Power, and many of them HAVE been done, but much less commonly. Also launch sites, while still challenging especially in drought conditions, still far much more readily available than high power.

disadvantages of low power: less shock and awe compare to high power. Also lower altitude due to two factors, first the motors are obviously smaller. second (although this too is in process of changing), tracking and recovering a small rocket that goes out of sight and site (likely if it goes over 2 thousand feet) without electronic trackers is sketchy, although FlightSketch may have a tracker that can fit a low power rocket soon, and Jolly Logic has dual deploy for larger low power rockets and I have heard rumors may have something for smaller rockets as well.

mid power? Pretty much the same as low power to me, but a bit more shock and awe, as they are larger, and can carry payloads Such as larger cameras, CAN fly higher (although motor choices can be made to keep them in range on smaller field if wanted) and are much more electronics friendly if that’s (one of) your thing(s). Cost is a bit more, and you need to build a bit stronger.

yes, this diatribe does have a point. There are only two key rules in model,rocketry.

1. Be safe

2. have fun.

doesn’t matter if your rocket weighs a fraction of an ounce and only goes up 50 feet or weighs a few hundred pounds and approaches the Karman Line, it’s YOUR rocket, and as long as those two rules are applied, don’t worry about what anyone else thinks!
Well said
 
Brock, I completely agree. I have been in and out of this hobby 3 or 4 times in my life for a total of about 30 yrs in the hobby and I'm just now starting to play around with MPR and HPR. I have been a LPR guy my entire life mostly due to the simple fact that I live outside of Chicago and there is NO WHERE around here to fly even MPR unless you have a heavy rocket. I'm familiar with the Bong Rec. area in WI and it's a nice place but there are way too many places for a water landing. Not to mention that most weekends are booked for the special use area. This bit me in the ass last weekend but that's another rant altogether.

I've too love the old Estes, Semroc, Quest, Custom kits. The designs are wonderful and I really enjoy building them. Since returning to the hobby, we have a place in AZ that we found that is large enough to fly just about anything I would ever put in the air. I've been close to 5K feet. with a Apogee kit a couple of times and actually got it back once :)

One of the aspects of the hobby that I have found that I really enjoy is upscaling some of my old favorites. Rockets like the old Ninja, Wizard, Sizzler, Hawkeye that were originally small BT20/BT50 kits can easily be upscaled to BT60 and BT80 and still fly on the Estes D and E motors. The Upscale builds I'm working on and planning will be light enough to put up a few hundred feet here at home with something like a E12-4 but will be shipped to AZ where I can stretch their legs with larger 29mm composites.

Then there is the question of what is LPR and what is MPR. For me it's simple and I know this isn't the technical definition so no one needs to correct me :) LPR to me is Estes Black Powder motors. 13 to 24mm, A thru E.

MPR are the Composites motors like the Aerotech stuff. Things like the E20, E30, F44, F67 etc. Again, Not technically correct but this is where I make the distinction.

At the end of the day, it's your hobby. Build what you like, fly what you like and be safe out there.
 
I like LPR because they are lower priced and easier to build so I can have more to choose from when I get ready to go to a launch and I won't be as devastated if I lose one. Also the engines are less expensive and easier to get so I can make more launches. I like B through D engines and I find my Big Daddy to be fun to launch.

I do have some MPR and a couple of HPR, and I've been level 1 in the past. I want to dust off my MPR and launch a few and might even do level 1 again, but most of my launches will always be LPR.
 
So, how about talcum powder. Do you slather the parachute in Johnson's Baby Powder like I do? I make it ridiculously powdery. It still doesn't open up every time. Argghh!
Take care. Johnson's Baby powder today is cornstarch, not talcum. It can ignite and it can put pinholed in your parachutes, partly melt them, etc.

BAR here too at 61 years young. I'm loving the hobby even more than I did as a teen because I have FUNDS now! I stopped into Hobby Lobby today to by some D engines and ended up leaving with a Baby Bertha. $7.99! How could I pass that up? BIG Bertha was one of my favorite rockets as a kid. It was orange. It took off slower which made it even more fun to launch. Not sure what happened to it.
My first rocket was the Estes Scout. Tumble recovery fun!

Now I have a workshop, more tools and 3d printer which opens up so many possibilities for modeling.
Amen, and amen! Funding is so important, and the patience, skills and analytical prowess I've developed as an adult are giving me a great deal of enjoyment.
 
I like LPR because they are lower priced and easier to build so I can have more to choose from when I get ready to go to a launch and I won't be as devastated if I lose one. Also the engines are less expensive and easier to get so I can make more launches. I like B through D engines and I find my Big Daddy to be fun to launch.

I do have some MPR and a couple of HPR, and I've been level 1 in the past. I want to dust off my MPR and launch a few and might even do level 1 again, but most of my launches will always be LPR.
Sounds like a great approach!
 
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Hey, Brock,
You are in good company here in Colorado. I am a professed LPR BAR and having a great time with it. Several other of the local BARS I fly with are largely LPR.
Look forward to seeing you soon at one of our upcoming Dove Valley Park launches!
 
Low power is also extremely cheap compared to high power, and the variety is across the board. To me, the classic three fins and a nose cone gets pretty boring early on, but you can branch out into helicopter, AirBrakes, gliders (free flight and radio controlled), cameras, staging, scale models, fantasy style models, saucers, Odd Rocs (flying potatoes, hot dogs, cola cans, tape worms, Cranes, Skeletons, outhouses, the sky is literally the limit.). There is also competition for MicroMaxx and Low Power. Note all of these (except competition) CAN be done with High Power, and many of them HAVE been done, but much less commonly. Also launch sites, while still challenging especially in drought conditions, still far much more readily available than high power.

Note that I am L2 certified . . .

I started in Model Rocketry in 1967, at age 6 ( Dad built my 1st rocket ) . . . I joined NAR ( #26128 ), in 1974, to fly NAR "Pink Book" competition . . . Before HPR was "legal", I flew rockets well outside the Safety Code, starting around 1979, usually clusters of FSI F100 motors, and I joined Tripoli in 1986 or 1987 ( #517 ).

Even though I am HPR-certified, my "first-love" is Estes BP motors, 1/4A - F impulse. I get much more satisfaction out of that than HPR. To me, HPR was a lot more "fun", when it was "illegal" and, today, it has become more about "showing off" and "one-upmanship" . . . Those with the deepest pockets "win".

There is MUCH more "camaraderie" in LPR than there is is HPR, in my experience . . . For me, that is what the Hobby is all about, sharing ideas, learning, and helping others.

Dave F.
 
Many HPR flyers look down on Model Rockets, as being "toys" . . . Unfortunate.

Dave F.
It’s only unfortunate if you take it seriously.

Regarding High Power Rocketry, I just watched Shrek (again) and enjoyed the reference to the size of Lord Farquaad’s castle.

for the record, I went to NSL a couple years back and enjoyed the show, and I have three mid power rockets of my own. As @georgegassaway says (slightly different context), “it’s all good.”

my advice is start with basic 3FNC (or 4FNC if you are a radical!) low power to learn the ropes, read a little (or a lot) about other types of rocketry (not just sizes like High, Mid, and MicroMaxx but also different things like scale, fantasy, gliders, helis, airbrakes, now with @Dotini crunching them out, Horizontal Spin!), ideally attend a club launch where multiple types are launched, and find your own niche.

it is fine to tease others about their different tastes, but at the end of the day make sure it’s all in good natured fun. While there are certainly lots of WRONG ways to do Rocketry, these generally fall into the “Idjit” category, and this category has members from MicroMaxx to HPR, and is usually defined as a practiced disdain for the NAR safety code. I think aside from the two rules I have given above, I don’t think there is Any single “Right” way to do it.
 
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Many HPR flyers look down on Model Rockets, as being "toys" . . . Unfortunate.

Dave F.
It’s only unfortunate if you take it seriously.

What I meant is that many young or new Rocketeers might be "chased away" from Rocketry, if their efforts are being "put down" by other Rocketeers ( especially HPR flyers ), with a "superiority complex" . . . That would be "unfortunate".

Dave F.
 
Pic of Avatar please! :)
I love sci-fi looking rockets, especially "Dieselpunk" ("Flash Gordon" and "Buck Rogers") type rockets.

I have begged the new owners of Estes to bring back the "Galactic Pirates" rockets from the early 1980's. I hope they consider my request!

I love the Galactic Pirate "Patrol Cruiser Excalibur".View attachment 474037
While you wait for Estes to bring it back, you can currently get a reproduction of the kit at,
http://morerockets.com/Reproduction-Rockets/Reproduction-Model-Rocket-Kits/Patrol-Cruiser-Excalibur
 
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