If you could only fly one diameter MPR or HPR motor range...?

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RocketBuff

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Hey Guys,

Okay... thought this might be a good "belly up to the bar" type of conversation on nothing too specific.

Say for some reason you could only fly one diameter of MPR or HPR reloads for the rest of your life... say you have 50 years left to walk God's green earth... and you intend on flying for all those 50 years and you have lower to middle income resources.

What would you fly?

24mm CTI or Aerotech or ?
29mm CTI or Aerotech or ?
38mm CTI or Aerotech or ?
54mm CTI or Aerotech or ?
75mm CTI or Aerotech or ?
98mm CTI or Aerotech or ?
Or...?

I have heard some people say for the money and the range of loads 38mm is pretty nice.

But then I have heard some people say 75mm for the money and power is also a good choice.

Assume you are whatever level flyer you want to be, but stick within the restrictions of lower to middle income resources.

Any and all thoughts or rants welcome!

-Eric
 

mikec

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These sorts of questions are really too open-ended to be meaningful. Some people want to fly as many flights as possible, some want to fly a few really big or complex flights, and everywhere in between. There are probably as many goals as there are rocketeers.

If flying relatively more smaller flights is what you want, it's hard to beat the 29mm Aerotech line with its hazmat-free shipping. Similar advantages for some of the 38mm AT and 38mm Loki.
 

prfesser

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I will second 38mm. You have every option from A to J (or...doesn't someone make a 38mm baby K now?) Versatile.

As for the airframe I'm I big fan of 4", which can be flown on a G or even an F motor. And can go to the limit.

Best -- Terry
 

NateB

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Can we adapt down too?

I'd go with 38mm Loki. G-K reloads are available with many hazmat free options and the ability to make sugar grains or adapt down for smaller motors. That would let me fly a wide range of rockets with only one system of cases.
 

Speaknoevil

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Can we adapt down too?

I'd go with 38mm Loki. G-K reloads are available with many hazmat free options and the ability to make sugar grains or adapt down for smaller motors. That would let me fly a wide range of rockets with only one system of cases.
I'd also go with Loki 38mm for the range of motors and loads balanced with cost. On the airframe, I would likely go with 3" canvas phenolic from MAC Performance for it's balance of durability and cost; moving down from 4" to get better performance from the 38mm motors.
 

JMX

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1) 75mm and 98mm too expensive and complex. No motor eject which adds to complexity and cost.

2) 54mm can go to to L impulse can get kinda pricey. Plus cases are more too.

3) 24mm and 29mm too small power wise even though they are affordable.

CTI 38mm and get the starter kit that gives you all the cases and spacers you need for G through J impulse.

The good thing about the CTI 38mm is you only have to buy the case. No extra enclosure hardware needed. You just get the cases and then buy the reloads. Easiest and most sensible reloading ever.

CTI 38mm gets my vote.
 

JohnCoker

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I agree with 54mm, but 38mm has good options too.
Here are the choices in 54mm (195): 54mm
and in 38mm (186): 38mm
Of course, if you restrict to a single manufacturer, it gets a lot smaller, but these are the most popular HPR sizes.
 

o1d_dude

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Given one diameter, one brand, moderate financials, I’d have to go with the 38mm Aerotech line.

Full disclosure: I have 29-54mm Cesaroni hardware as well as the Aerotech line. In my experience, Aerotech is just easier for me to acquire on the field and I don’t want to be known as “that Haz-Mat guy” in my neighborhood.
 

beeblebrox

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I prefer making my own motors...24mm, 29mm and 38mm are the favs, but 18mm is fun and challenging! Cheaper than reloads...
 

Flyfalcons

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Personally I think some of the best motors in a reasonable price range are found in 54mm flavor, but some of them require altimeter deployment. So if you don't want to mess with that, that precludes using those motors. You can fly a wide variety of rocket airframes on 38mm, and the big J570 on 38mm is no joke of a motor. I could probably find enough enjoyment with only 38mm motors to fly those exclusively if I had to.
 

hobie1dog

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1) 75mm and 98mm too expensive and complex. No motor eject which adds to complexity and cost.

2) 54mm can go to to L impulse can get kinda pricey. Plus cases are more too.

3) 24mm and 29mm too small power wise even though they are affordable.

CTI 38mm and get the starter kit that gives you all the cases and spacers you need for G through J impulse.

The good thing about the CTI 38mm is you only have to buy the case. No extra enclosure hardware needed. You just get the cases and then buy the reloads. Easiest and most sensible reloading ever.

CTI 38mm gets my vote.
+1 exactly, living on SS Income dictates an affordable decision
 

jqavins

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38 mm. I have the CTI 3 and 6 grain cases and two spacers, but I'd have to take another look at the market offerings before committing to a brand.

If I want to go higher power I become a cluster fan. CTI 6GXL reloads crack 1000 Ns, so a nice 7 motor cluster would be M class impulse.

And I'd pitch a fit if you also wanted me to give up good old 18 and 24 mm low power.
 

jqavins

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Hey Guys,

Okay... thought this might be a good "belly up to the bar" type of conversation on nothing too specific.
How about adding a poll to this thread? There isa limit to the number of poll choices, so I think you'd only be able to include diameters.

Incidentally, since responding 38 mm, I've waffled over my second choice and settled on 29 mm.
 

John Kemker

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Definitely 38mm Loki. Most of the reloads are non-HAZMAT shippable and you can go from a G through K impulse. Plenty of nozzles available for Research motors, including an idea I had for trying a single-grain F motor...
 

BDB

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I agree with everyone who posted 38 mm Loki. That easily constitutes >50% of my HPR flights. The only caveat I would say is that most MPR kits have 29 mm motor mounts. For example, all of the LOC Park Flyers and the Estes Pro Series kits have 29 mm motor mounts. So if that is where you plan to start, you will need to invest in 29 mm DMS motors or some 29 mm hardware from either CTI or Aerotech.

This is really just another way of saying that I wish Loki still made 29 mm hardware and reloads.
 

Jozef

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1) 75mm and 98mm too expensive and complex. No motor eject which adds to complexity and cost.

2) 54mm can go to to L impulse can get kinda pricey. Plus cases are more too.

3) 24mm and 29mm too small power wise even though they are affordable.

CTI 38mm and get the starter kit that gives you all the cases and spacers you need for G through J impulse.

The good thing about the CTI 38mm is you only have to buy the case. No extra enclosure hardware needed. You just get the cases and then buy the reloads. Easiest and most sensible reloading ever.

CTI 38mm gets my vote.
X2
 

Back_at_it

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At this point in the hobby I think I would top out at 29mm. I've only flown a few of them as space is limited in my area so I can't see myself needing to go any larger. I don't see myself flying rockets heavy enough that I would need to go larger.

If I moved out west where spaces was unlimited I could see myself going up to 38mm
 
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grouch

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No question, for me it's the AT 29mm motors. I love both the AT and CTI 29mm loads but if I had to pick a single brand it would be the AT line simply because I can mail order the bulk of them without HAZ. This is exactly where I am at in my flying, I decided a while back to step back to 29mm because I like them the best for several reasons. I don't see myself building anything in the future with a motor mount larger than 29mm.
 

Jozef

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For MPR, I would say 29mm. you can always adapt down to 24mm. Lots of single use motors to choose from so hardware cost is not a factor.

For HPR, Id say a 54mm hole with adapter capability for 38mm. Again, good selection of single use motors from Aerotech. If one is income challenged, HPR can get expensive.....motors, altimeters, trackers, etc
 
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