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Do you build your motors and ejection charges at the launch or ahead of time?

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How much pre-prep do you do?

  • None. I build my motors and ejection charges at the launch.

  • Some. I bond motors that need case bonding and weigh out my ejection charges.

  • A lot. I build my motors ejection charges ahead of time but I don't install them in the rocket.

  • As much as possible. I pre-prep everything but I don't connect the electronics to the charges.

  • Everything. I have the rocket ready to put on the pad and turn on the electronics.


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ChrisAttebery

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I'm curious to hear what your thoughts are on building motors and ejection charges ahead of time. I've found that the more I get done ahead of time the more I relax and enjoy being at a launch. So, how much pre-prep is too much?

For the record I've been at #2 for a couple years. For the upcoming XPRS launch I'm at 2.5. I bonded my motor and built my charges. I'm trying to decide if I should complete the motor assembly and assemble the rocket, but leave the ejection charges disconnected until I get to the launch (#4).
 

djs

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I voted at #4, but sometimes I attach the charges to the electronics on the shear pinned side of the av bay beforehand. I don't really want to mess with shear pins, etc at a launch site.

Usually when I'm at the launch I attach the charges to the drogue side of the av bay, attach the tracker, pack the drogue chute, assemble the rocket (av bay into booster), and go.
 

djs

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One thing you also forgot to ask was batteries. I know some people put fresh batteries in at the launch (or that morning). I usually charge lipos the day before, and do a voltmeter test on 9v batteries. I don't want to have to mess with zip ties or whatever on the launch day.
 

Cl(VII)

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I voted 4, but I do usually have the charges in, and the magnetic switches hooked up. Typically all I have to do at the field is put the motor in the rocket, turn on tracker and fill out the flight card.
 

Dave A

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I load all motors ahead of time.
I load A/V bays with new batteries, ready to install, sans BP. I wait to see which rocket flies 1st, then load the charge.

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cerving

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I build the motors, charge the batteries, install the charges, and basically do everything except hook up the power (I'm using WiFi switches or Quantums, typically). You have to do all that in the field anyway since the AV bay has to be opened to connect the battery. Even with a mechanical switch, I don't connect the battery until I'm in the field. If I didn't do it the day before, I'll repack the chutes too.
 

Wayco

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I'm ready to fly when the waiver opens. Motors in and batteries connected. Usually my charges are prepped, but some of the larger charges are prepped at the launch. My pre-flight is install the tracker to the drogue shock cord, add dog barf, close it up and fill out the launch card. Some of the launches I already have launch cards done.
 

Ravenex

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I put four, but I'm between 4 and 5, I use mag switches so I charge the batteries a few days before leaving for the launch and prep everything as far as possible. My rockets both separate on both sides of the av-bay and are easier to transport broke in half. My charges are very small 0.14g in my 54mm and 0.3 in my 4" so I make them with the tip of a glove and tape so they're not as protected as charge wells. Since I don't want to have them hanging free off the av-bay I prep the side that's more difficult if it comes loose with the charges and pin it at home. I pack the other side and cover it so the chutes stay in place. When I get to the field I put in the charges on one side of the bay, pin the halves together, turn on the tracker, and head for the flight line. On my rocket ExPAC there is a bit more prep because of the stabilization system, I bolt the canards on at the field.
 

michigander

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#3 motors built and charges @ home night before , , launch sight is 3 1/2 hr drive each way less work at site

note if flying Motor deploy I don't add BP until prepping rocket on site
 

OverTheTop

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The more you do at home the more SNAFUs you find in advance. Makes for a relaxing and social launch day.

I usually start prep around a week before for any dual-deploy flights. Checklists are essential as over the days you need to remember what has been done and is still to do.
 

farsidius

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I only pre-prep my charges at home. I never assemble a motor (unless it needs bonding) until I'm at the field and have assessed the flying conditions for that day. Weather can be finicky in some parts of the country. (this was more of a problem when I lived on the east coast) And, as much as possible, I bring 2-3 motors for each rocket (yes, I hoard motors) so I have a choice and can always fly something.

-brant
 

markkoelsch

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I prep as much as I can at home. Usually that means everything except for tracker and nosecone shear pins.


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Handeman

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I voted 5, but it really depends on the rocket and motors. I will pre-build my EX motors, but not commercial, especially the 38mm and smaller. I don't use motor eject for EX so the charges get assembled and connected to the ends of the av-bay on the larger rockets the night before. With a DD rocket and EX motor, everything is ready to go, just turn on electronics, insert igniter and launch. The EX powered rockets will either fly or not, the commercial motor rockets get a choice to match conditions. Wind conditions, cloud deck, etc. are all things that affect the choice of motors and can't be determined the night before, so commercial motors get assembled at the launch.
 

dhbarr

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Very much depends on Real Life. Optimally I'd like to be 100% safe-ready day of, but usually I fall well short.
 

Buckeye

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#5 Everything, including flight card.
 

djs

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I would also say this is weather related.. if it's a 20F day at QCRS in Princeton, IL.. it's not easy to wire things up with gloves on :) If it's 80F in summer at Bong, I have more time and inclination to do stuff at the launch site.
 

seth_cooper

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Everything prepped and ready the week before the launch.

Launch day I turn on the electronics and insert the igniter.
 

mpitfield

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I am in the some category, but admittedly the more I do this the more I move towards the everything category.

I fly Loki, CTI and Aerotech so a lot of the prep depends on what I am flying. If a Loki 54mm and up I bond the grains even though you don't have to bond them on most 54mm loads, but it can't hurt and like most of what I do, it is good practice. For CTI if there is a delay grain I will adjust it ahead of time but beyond that, up to 54mm anyway, I just leave the motor prep for the field. Aerotech is one that I like to prep and assemble in my hotel room, which is a new a new thing for me.

Deployment charges I weigh the night before, as well as test and wire the e-match and charge up my Li-Pos, then at the field I connect my Li-Pos, do a continuity and voltage test, turn off then do the final prep on the charges.
 

Binder Design

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I'll build motors way ahead of time, but I'm not driving around with prepped charges in the car, disconnected, shunted or otherwise.
 

emckee

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I will charge batteries in the week ahead of the launch and pre-build motors generally the night before the flight. Deployment charges and other BP are kept separate and unassembled.
 

Nytrunner

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I like to prepare as much as possible.

Allows for more interaction and sightseeing at the actual launch (provided I keep away from those that DO like to do it all at the launch lol)
 

patelldp

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Do it all aside from turning electronics on. I'm paranoid about it though, so I make sure that any charges or components that are separated by charges are perpendicular in the car and not pointing at passengers. I also make sure that any screw switches have the heads facing toward the ground. The vibrations of the car could cause them to close while driving, I'd rather lose a screw than make a connection.
 

muddymooose

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Before I started going to club launches I thought I would be anxious about having stuff ready ahead of time. Now that I've been to club launches I've realized it's pretty laid back and I have all day to get stuff together. I'll assemble motors and prep stuff in between watching launches. No rush, makes for a nice long relaxing day.
 

Handeman

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Before I started going to club launches I thought I would be anxious about having stuff ready ahead of time. Now that I've been to club launches I've realized it's pretty laid back and I have all day to get stuff together. I'll assemble motors and prep stuff in between watching launches. No rush, makes for a nice long relaxing day.
That's fine if you aren't doing some time at LCO/RCO, catching up with friends you haven't seen since the last launch, gawking at the new rockets that show up, debating the ins and outs of various techniques, helping the new guys assemble motors for their cert attempts, helping the TARC teams, or just being a nuisance to anyone that will put up with you for a while. By the time you've done all that, the launch is over and you haven't prepped a thing..... Had a great time, absolutely, but not much in the air..... Any I wonder why I only get one flight in some days....
 
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