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Who's used an Eggtimer for airstarts?

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fyrwrxz

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Title says it all. Looking to upgrade a big bird from brand "a" to (my) new Eggtimer. Pics, tips or tricks? I think I can make a sensitive enough "starter" (really hate that term!) to fire off 2 CTI 29mm motors using 3X 2032 batteries. Or just go with a separate lipo. no ground test have been done yet, so it's a work in progress.
 

Tonimus

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I would just use a separate lipo. I've not done any airstarts with one, yet. Plans for The Neutral Zone include two Eggtimers firing three 29mm motors each.
 

blackjack2564

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"Most" 29 CTI [not V-max ] use the BP pellet in top grain of motor. Started by regular ole low current "match"/starter.
Just check the CTI package, where starter is taped on. It should contain a plain match or folded & dipped with pyro one. Either way it's a low current unit & you should be good to go.

I have fired them with a 2032 coin cell or lipo's.

By the way old man......you probably know this & forgot.[like I did today looking for my keys for 45 minutes.....when they were in my hand the whole time]
Split/cut casing from a C motor, remove the BP slug....hard as rock....cut a 1/2 in. section off/box cutter.... press fit into top grain of any motor and you can light it with a low current starter/match!

So no need to make a sensitive starter.... Don't ya just hate that type, I'm always afraid I may hurt their feelings!

PS... you been banned from Hershey Pa. or just went on the "wagon" for chocolate?
 
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fyrwrxz

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"Most" 29 CTI [not V-max ] use the BP pellet in top grain of motor. Started by regular ole low current "match"/starter.
Just check the CTI package, where starter is taped on. It should contain a plain match or folded & dipped with pyro one. Either way it's a low current unit & you should be good to go.

I have fired them with a 2032 coin cell or lipo's.

By the way old man......you probably know this & forgot.[like I did today looking for my keys for 45 minutes.....when they were in my hand the whole time]
Split/cut casing from a C motor, remove the BP slug....hard as rock....cut a 1/2 in. section off/box cutter.... press fit into top grain of any motor and you can light it with a low current starter/match!

So no need to make a sensitive starter.... Don't ya just hate that type, I'm always afraid I may hurt their feelings!

PS... you been banned from Hershey Pa. or just went on the "wagon" for chocolate?
LOL, brother! Stay tuned on your private channel as I have some hilarious 'reports from the field' FYEO! Not a recovering chocoholic-tried pastries and then bubblegum as substitutes, but I kept swallowing everything. Back to liquor and candy bars and I feel so much better!
 

dixontj93060

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By the way old man......you probably know this & forgot.[like I did today looking for my keys for 45 minutes.....when they were in my hand the whole time]
CJ, no problem we all know you were in deep concentration thinking about that super-duper two-stager--and with that kind of cipherin' going on, who cares about what is in your hand, right?!
 

KenRico

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There is a AUX board kit available for the original eGGtimer if you are not utilizing eMatch for ignition.

The above is the eGGtimer Rocketry eGGtimer altimeter & aux board NOT the one from your kitchen.

I can just imagine Fyrwrxz in front of the RSO arguing for his mechanical eGGtimer with a 6v latern batt strapped to the side of the rocket wired directly to the airstarts "you can twist the dial a hundred times..and it will work a hundred times 100 percent accurate! Before altimers we launched some PETs as timers ..and this is better because the timer doesnt need a battery!"

BTW .. at LDRS Fyrwrxz was wearing an ascot everday , trying to hone in a CJ signature move

Kenny
 
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blackjack2564

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CJ, no problem we all know you were in deep concentration thinking about that super-duper two-stager--and with that kind of cipherin' going on, who cares about what is in your hand, right?!
Your probably correct, the problem is.....I don't remember!!!

BTW .. at LDRS Fyrwrxz was wearing an ascot everday , trying to hone in a CJ signature move

Kenny
Quite the stylish move, I must say!

Although the REAL purpose is to keep from eating dust at so many of those sites where dust devils magically appear.
Of course both of us being old farts & coming from the days of trying to "be prepared".....one never knows, when you may pass a bank or gas station, that is in dire need of "quick funds removal".

This small accessory to ones attire,when pulled up into 'full use mode,' with the addition of 'cool shades'....is a must for keeping old Pyrate's identity discreet.:dark:

Glad to hear your back on grog & chocolate, no true Pyrate can go without sustenance.

Ps Bubblegum has shown a few endearing qualities....plugging holes in leaky bilges.
 
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michigander

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3 channel.jpg

not flown yet 2 stage , I have used as back up drogue testing

onsite motor vendor is going to help with making ematch work for 2nd stage motor ignition

Pic of aux board
 

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fyrwrxz

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View attachment 294814

not flown yet 2 stage , I have used as back up drogue testing

onsite motor vendor is going to help with making ematch work for 2nd stage motor ignition

Pic of aux board
Now THAT is a sexy layout! Pure rocket porn! (there is a joke in there about slutter switches, but I ain't gonna go there!) Thx for the pics!
 

cerving

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Personally I'd use a small LiPo and your favorite dipped ematch (or undipped, for CTI) for sustainer ignition. The Eggtimer won't care... it can pretty much light anything given a big enough battery.

Read the section on airstarts in the manual. Twice. Then again. Then memorize it. For airstarts to work safely and reliably you need to properly set 1) Your CHB setting (breakwire or no breakwire...) , 2) Your CHB "firing time", 3) The LDA, 4) The Burn Timer, 5) The Airstart Delay, and 5) The Minimum Velocity at Airstart setting (if you use it, but highly recommended by TRA). That sounds like a lot, but it's really no different than any other flight computer that will handle airstarts with proper time/velocity controls. Perform a good sim with OR/RocSim, set the Eggtimer to match the sim, and you'll be just fine.
 

fyrwrxz

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Just so everybody knows- KenRico(suave') IS my PR agent!
 

fyrwrxz

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Personally I'd use a small LiPo and your favorite dipped ematch (or undipped, for CTI) for sustainer ignition. The Eggtimer won't care... it can pretty much light anything given a big enough battery.

Read the section on airstarts in the manual. Twice. Then again. Then memorize it. For airstarts to work safely and reliably you need to properly set 1) Your CHB setting (breakwire or no breakwire...) , 2) Your CHB "firing time", 3) The LDA, 4) The Burn Timer, 5) The Airstart Delay, and 5) The Minimum Velocity at Airstart setting (if you use it, but highly recommended by TRA). That sounds like a lot, but it's really no different than any other flight computer that will handle airstarts with proper time/velocity controls. Perform a good sim with OR/RocSim, set the Eggtimer to match the sim, and you'll be just fine.
Cris-Hopefully you'll see it in Vegas or at Roc later this year. I gotta tell ya, that is an excellent manual you wrote up! I can't remember which launch it was you brought the proto to, but you went thru it twice with me. I still can't believe the flexibility! Thanks for the fun at LDRS-the Dude was sooo cool! (and thanks for not putting my name on it!)
 

cerving

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So, what are you building? I'm still looking for the "right" 2-stager... preferably 38mm to 29mm. 3" to 54mm LOC tubing would work, I'll probably end up making something custom...
 

fyrwrxz

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So, what are you building? I'm still looking for the "right" 2-stager... preferably 38mm to 29mm. 3" to 54mm LOC tubing would work, I'll probably end up making something custom...
Me too! I've got too much glass around and it's heavy, so maybe try some of that new canvas phenolic stuff. I could go way old school with paper like in the early 90's? We'll see.
 

woferry

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Every time I see robbdm's RW Double Shot fly I wish I had bought that kit when it was on their Wednesday discount. Seems like that one hasn't shown up on Madcow's site yet (at least when I looked a few days ago). Not quite 38-to-29, if I recall it's 54-to-38 (or maybe 75-to-38). I guess I should ping them on that one, seems like the only unique part would have been the ISC since it's also a transition.
 

Tonimus

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Cris, if you're still keeping an eye on this thread, how many First Fires or First Fire Jrs do you think an Eggtimer could fire at once with a 3s lipo?
 

cerving

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Cris, if you're still keeping an eye on this thread, how many First Fires or First Fire Jrs do you think an Eggtimer could fire at once with a 3s lipo?
How many do you want to light? Four shouldn't be a problem... ground test first, of course. I don't have an all-fire current spec for the First-Fire.
 

KenRico

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I have an extra 6 inch nose cone. .may have to make something for a cluster and try this out.

Kenny
 

Tonimus

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How many do you want to light? Four shouldn't be a problem... ground test first, of course. I don't have an all-fire current spec for the First-Fire.
Six, total. I figured that would be too much, so I planned to use two Eggtimers to light 3 each.
 

cerving

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Six, total. I figured that would be too much, so I planned to use two Eggtimers to light 3 each.
If all six are going to be clustered you need to fire them with one Eggtimer. Ground test all six, pretty good chance it will be fine.
 
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