I feel the same...I mostly fly F and G loads in this, but have never had a need to build the igniter into the motor during assembly. Sometimes I've had to with copperheads in the 24/40, but never with anything in the 29/40-120.I have found that a lot of the time, the 29/40-120 igniters fit through the nozzle and don't need to be installed before the motor is closed up, but I test the fit of the igniter tip through the nozzle before assembling, just in case. At the pad, I have to feel around a bit with the igniter tip to find the slot but that's not a big deal. The one thing I should note here is as of late I almost always fly G's in my 29/40-120, and I don't know if the nozzles for the E's and F's might have smaller throats.
I have both the 24/40 and 29/40-120 cases. I like them, especially the 24mm. But there is a bit of a hole in the motor offerings. There is no real "mid-F". The 24/40 ends at 49.7NS, and the 29/40-120 picks up at 73Ns for the F52. I'm ignoring the F22, as it doesn't have enough oomph to give stable rod velocity for anything I have. The 24/60 offers some relief with motors up to 57Ns. But I'm not finding it worthwhile to spring for the 24/60 case just for a few use cases. So I supplement my reloads with the F67 (61Ns) single use, which happens to be non-Hazmat.
Like I said in Post #34:The hole pretty much disappears if you include the 24/60.
Like I said in Post #34:
"The 24/60 offers some relief with motors up to 57Ns. But I'm not finding it worthwhile to spring for the 24/60 case just for a few use cases. So I supplement my reloads with the F67 (61Ns) single use, which happens to be non-Hazmat."
Even with the 24/60, there is still a gap from 57Ns to 73Ns.
If you are not going above F the 40/120 case is the way to go. It more different reload options then any other case. I use mine more than any other reload case I and I have a lot, my casings range from 18mm all the way to 54mm, but I have not yet flown the 54mm casingsOk, I'm going to admit to being a doofus when it comes to reloadable hardware. I'm still so new to this. However, it seems that the Aerotech RMS 40/120 case is a popular place to start learning, however, it appears that the 40/120 is different from all other reloadable hardware. The reloads for it are case-specific and even the forward and aft closures are case-specific and won't fit any other 29mm cases.... which is making my head spin.
All that said, how in general does this all work? It appears to me that the longer 29mm tubes are for higher power G and H reloads as I assume they take more "grains" and therefore are for flying 3000+ ft, which I am currently not planning for the next year or so.... SO, I'm looking to start with the shorter 29mm reloads since I don't want to go beyond F, although I may want to stray into "G" territory by the end of 2023 (or at least give it a try).
Anyhow, the 40/120 seems to be the place to start -- but the question is what makes this way to go, and/or is there a better option?
Here are my requirements:
#1) I want to start small -- this is going to work in both 1.6 diameter to 3" diameter rockets, using F power mostly.
#2) IF I want to go into "G", is this still the case to use or do I need something bigger?
I'm currently using single-use F motors in these rockets, but I'm thinking down the road I need to learn about this stuff as I'm hoping to try for L1 in 2024.
Red and green color are subtle below "H". As it was explained to me: Bigger motors burn a whole lot more at once.It is tempting to get a 24/60 case, however, because it offers some different propellant types - like the Redline. Might be worth the price of entry just to see the red flame.
I always test fit the igniter in while I was building. My reason is because different reloads had different length grains so if I fit the igniter in while building the motor I could be sure that the igniter head was positioned at the front end of the fuel grain. I would test fit the igniter through the nozzle and grain, fold the igniter around the end of the nozzle then take it out and carefully set it aside. Then after building the motor I could put the igniter back in and know that the igniter was positioned correctly.I have found that a lot of the time, the 29/40-120 igniters fit through the nozzle and don't need to be installed before the motor is closed up, but I test the fit of the igniter tip through the nozzle before assembling
A sharpie mark on the wire right where it enters the nozzle works well. And is simple.I always test fit the igniter in while I was building. My reason is because different reloads had different length grains so if I fit the igniter in while building the motor I could be sure that the igniter head was positioned at the front end of the fuel grain. I would test fit the igniter through the nozzle and grain, fold the igniter around the end of the nozzle then take it out and carefully set it aside. Then after building the motor I could put the igniter back in and know that the igniter was positioned correctly.
|F41-7||46 N-s||1645 ft|
|F35-7||58 N-s||1944 ft|
|F30-7||74 N-s||2386 ft|
I highly recommend getting the Zephyr. I have one and love it. It was very easy to build and you can use it for your Level 1 cert flight. It comes with a 38mm mount but it's easy to use a 38mm to 29mm adapter for less expensive motors. If the Zephyr is your first high power capable rocket, Apogee has video instructions making the assembly almost fool-proof.Not just that, but @heada has me thinking I should *also* get the 24mm reloadable as that could also lead to some extra excitement with my existing batch of 24mm rockets. But yes, I know what you are saying as I clearly see a 4" Zephyr and a 38mm motor in my future only 12 months or so down the road. But we'll see. Maybe I'll run out of money before that (although I understand they pay pretty good for a kidney these days).
I'm still a bit of a chicken over higher altitudes, given that most of my flying fields have trees or other hazards nearby. So my ventures into F motors is with bigger, heavier rockets, like my North Coast Bounty Hunter. In that, little Fs are basically unflyable (~300ft), mid Fs are comfortable (548ft), big Fs (822ft) need to be reserved for places with fewer trees. (These are altitudes actually reached.) So I'm flying mostly with the mid level F67. I have a couple venues that I go to maybe twice a year that can easily handle G class, but for anywhere local I need the mid level.I'm not certain how much of an issue the "hole" in the mid-F range is, in practice. I ran quick and dirty Open Rocket sims on the Estes Hi-Flyer XL with three different F motors. There are, of course, differences in performance but how big are those differences?
I couldn't do a screenshot so here's a summary. Going from baby-F to mid-F increases apogee by about 300 feet or 18%. Mid-F to full-F, a bit more than 400 feet, 23%. To me, a difference of 300-400 feet on a flight to 2000 feet isn't terribly significant unless you have a target apogee in mind; YOMV (your opinion may vary )
The differences in average thrust and burn time undoubtedly have some effect as well, though I doubt those effects will be very large.
Motor Total impulse Apogee F41-7 46 N-s 1645 ft F35-7 58 N-s 1944 ft F30-7 74 N-s 2386 ft
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