LPR / MPR / HPR: What's the Easiest Size of a Rocket to Build.

In regard to building a rocket, what have you found is the easiest rocket size to build?

  • Low Power - Single Motor

    Votes: 9 27.3%
  • Mid Power - Single Motor

    Votes: 17 51.5%
  • High Power - Single Motor

    Votes: 9 27.3%

  • Total voters
    33

lakeroadster

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I've come to the conclusion that MPR, 2-1/2" to 4" diameter, are the easiest rockets to build. LP rockets just seem to be tedious during construction and are so delicate they are easily damaged.

I'm betting that a lot of LPR folks don't realize that and would really enjoy MPR, and that they don't realize the HPR Level 1 rockets aren't as difficult to build as they might imagine.

I'm wondering if that's the same thing you folks have experienced. :dontknow:

This isn't about price... just the build itself.

Thanks!
 

neil_w

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I have not built all three sizes so I didn't answer the poll... but I would say that for sure, as size gets smaller, certainly things get more difficult, especially finishing. Sanding and painting rockets with very small nooks and crannies is a real chore. And my getting-older-eyes aren't too happy dealing with really small stuff anymore. I admire the Dr. Zooch stuff but it's not for me.

For me, anything in the 1.3"-2.2" size feels very comfortable, with 1.6" probably the sweet spot. I haven't built anything yet larger than that.
 

boatgeek

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Midpower because you can be less concerned about final rocket weight. If it’s a little heavy, throw a higher thrust motor in. The QJets have changed that equation a little though.

Once you get to high power, 4” and above is a lot easier to work in than 3” and below. It helps to be able to get your whole arm inside.
 

Bruiser

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I like to build in the 2 to 3 inch range using 29mm motors. I can add details and don't have to worry so much about weight. You can also use most of the same materials and techniques as in lpr, some with slight modifications.

I do have some 24mm stuff that I built back when I was finding my feet as a BAR. I still haven't flown most of them.

-Bob
 

Daddyisabar

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Low power with plastic fin cans like Apha III are the easiest to build. Sleek, lovely 3-4FNC rockets that fly great, are safe and give great amusement. Mid power beauties like the Estes Pro Series could be easier for the shaky, nearly blind and somewhat forgetful old dudes. Any HiPo needing to mix epoxy is a whole other level above.

The more complexity, the more misery. Tiny scale kits like the Flis 1B skill level five are on the other end of the scale.

Smaller, crazy scratch builds with too many motors and lack of fins or fins and motors in the wrong places are the worst. ;)
 

Handeman

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I haven't built anything except fiberglass with electronics in years, but remembering back, a 4" cardboard with 38mm to 54mm MMT with motor eject is about as simple and easy as it gets. Big BT, big MMT, easy to handle parts, wood glue all around.
 

techrat

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I find that LOC 1.6" to 2.6" tubes are the best size for my hands.
They are substantial enough to take a bit of knocking around (no chance of getting destroyed in the car on the way to the launch). The smallest tube I can work with these days is BT-55, and even that I think I'm trying to move away from and build bigger. And yep, that's all MPR, with 29mm Motor tubes in the 1.6 to 2.6 category. I took the poll -- but be aware that I have never built an HPR rocket yet... a 3" diameter 3-1/2 foot tall "American Daddy" is the biggest I have built (w 29mm motor mount, so MPR), and I have a 3" dia, 5-foot on it's way to me from BMS, to be built over the winter, but again, still MPR. So currently, MPR is my happy place.
 

DRAGON64

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2.6" has always been the sweet spot for me to use in mid, and the low to mid high power range. Once you go above this size airframe, the use of materials and consumables (i.e. epoxy adhesives and paints etc) goes up exponentially. 4" is a nice step up, and 5.5" is nice for being able to "turn wrenches" on.

These are my 3 favorite size airframes.
 

Zeta

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I enjoy building rockets in a wide range of diameters....but the thing that gets me is trying to make filets inside when the gap between MMT and the airframe is tight ... maybe a foam pour is the way to go there ?
 

Donnager

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I could write a short book on why the 4" dia airframe is the sweet spot, but chp. 1 would be about getting your hand inside the airframe. :)

Mine might mention that in the foreword. I've realized that all my long wire hooks, loops, & fish tapes are unnecessary when the airframe goes above 3". Putting internal fillets on a 6" or 8" is childs play compared to a 3" with a 54mm hole.

I was really liking the big mid power and small high power stuff, but packing recovery gear, electronics, chute releases, and trackers make those difficult to fly with sporty motors at our site.

I'm generally moving toward one or two 4"+ flights (with a couple of motor options, depending on conditions) per club launch rather than trying to jam half a dozen different sizes in.
 

jqavins

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Once you go above this size airframe, the use of materials and consumables (i.e. epoxy adhesives and paints etc) goes up exponentially.
I suspect that's quadratically or cubically.

Anyway, I rarely build anything that requires any real internal work, so small is fine. Little tiny things can be a bit fiddley to handle and anything BT-50 or smaller doesn't have room for parachutes. Big ones can be ungainly and need cubically more time on finishing. I'm happy with BT-60 for most things, but maybe a little bigger would be a little easier. With internal structures to build, three to four inch would probably become my go-to.
 
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