Dual Deploy G-Force

Onebadhawk
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Bat-mite said:
I don't think I have seen anyone plug the igniter wires directly into the altimeter before. How are you going to prevent the ejection gasses from getting into the bay? Are you going to use putty, and add it and remove it each time you insert a new igniter?
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I've flown this way many a time. The key is that you drill a hole just large enough to feed the wire from the ematch through, as that alone will pretty much plug the hole, and then on the end of the wire you are attaching to the altimeter, tie a simple knot a bit further away from the place where the wire would hit the bulkhead when it's all assembled. The knot will act as a strain relief so that you don't accidentally disconnect the ematch from the altimeter, and also will pretty much finish sealing the hole in the bulkhead where the ematch passes through.

I've never used any putty, and never had any damage to the altimeter - YMMV.
 
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RecoRocket said:
I've flown this way many a time. The key is that you drill a hole just large enough to feed the wire from the ematch through, as that alone will pretty much plug the hole, and then on the end of the wire you are attaching to the altimeter, tie a simple knot a bit further away from the place where the wire would hit the bulkhead when it's all assembled. The knot will act as a strain relief so that you don't accidentally disconnect the ematch from the altimeter, and also will pretty much finish sealing the hole in the bulkhead where the ematch passes through.

I've never used any putty, and never had any damage to the altimeter - YMMV.
Click to expand...

Thanks. I like to learn new techniques!
 
Hey how are you guys :) I Got the g force too i flew mine 2 weeks ago They Had too send me a motor an coupler the parachute didnt deploy i Was told too add 4fg powder too help it. Havent try it yet

1408656280882.jpg
 
wildbill126 said:
Hey how are you guys :) I Got the g force too i flew mine 2 weeks ago They Had too send me a motor an coupler the parachute didnt deploy i Was told too add 4fg powder too help it. Havent try it yet
Click to expand...

Yes I add a little more to the ejection charge as well but taking out the cooling mesh and using a kevlar blanket makes a world of difference. Besides it is always getting clogged up. Also do a ground test first to get the BP amount right.
Wrecked my first one when I tried to fly it with the mesh in and a motor that didn't come with enough BP for the ejection charge. Learning the hard way usually gets expensive but in my case Aerotech replaced the rocket.
 
race 58 said:
Yes I add a little more to the ejection charge as well but taking out the cooling mesh and using a kevlar blanket makes a world of difference. Besides it is always getting clogged up. Also do a ground test first to get the BP amount right.
Wrecked my first one when I tried to fly it with the mesh in and a motor that didn't come with enough BP for the ejection charge. Learning the hard way usually gets expensive but in my case Aerotech replaced the rocket.
Click to expand...

This! If you are using motor deploy, definitely check the coupler before each flight and swap the baffle for a chute protector.
 
Got a website where i can fine one or someone that has one laying around? Thanks for information
 
Thank you just too let everyone know i have learning troubles Im just trying too injoy this hobby :)
 
race 58 said:
Yes I add a little more to the ejection charge as well but taking out the cooling mesh and using a kevlar blanket makes a world of difference. Besides it is always getting clogged up. Also do a ground test first to get the BP amount right.
Wrecked my first one when I tried to fly it with the mesh in and a motor that didn't come with enough BP for the ejection charge. Learning the hard way usually gets expensive but in my case Aerotech replaced the rocket.
Click to expand...

The first thing I do when building any kit is throw away the elastic shock cord, and use TN and or Kevlar instead. The second thing is put any baffle or piston into my parts box and forget about then.

The Nomex shields (they aren't usually kevlar, as you don't need the strength, just the heat blocking) are the best way to go, IMHO. Many online site offer them from 3"x3" and up.. 6x6, 9x9, 12x12, etc A 3x3 is around $4, and a 6x6 is around $5, and they are 100% reusable.

Another good way to protect chutes is cellulose insulation (last time a I bought any, a 1"x2"x3' bail of it was about $5 at home deport - and that is enough for about 5 lifetimes of flights!). It's ground up news paper, sprayed with a fire retardant (like the Estes "toilet paper" wadding). put some in the bird loosely, then the chute. Nomex keeps everything cleaner though!
 
Ya i renforce the coupler on g force i put fiberglass inside the coupler an sanded it down Nice an smooth i wish them parachutes Was like kevlar blanket i Got some old ones laying around from mirage. Mirage blow apart a few years ago from forward closure do too a seal my understanding.
 
Lowpuller said:
Drogue ejection charge video

[video=youtube_share;l7tsDRP2D18]https://youtu.be/l7tsDRP2D18[/video]



Main ejection charge video

[video=youtube_share;eMkJMdoy2Hs]https://youtu.be/eMkJMdoy2Hs[/video]


Sorry for the poor quality video


So many rockets, so little time, and money.
Click to expand...

Just my :2: so take it for what it's worth, but to me, it looks like too much charge for both charges. You only need to separate the two halves enough for the drogue to get in the air stream at apogee. Too large of charge leads to main chute deployments at apogee, which lead to shear pins and too long of shock cords and other complicating methods to compensate. Blow it out or blow it up is not a good design principle for recovery systems.
 
Handeman said:
Just my :2: so take it for what it's worth, but to me, it looks like too much charge for both charges. You only need to separate the two halves enough for the drogue to get in the air stream at apogee. Too large of charge leads to main chute deployments at apogee, which lead to shear pins and too long of shock cords and other complicating methods to compensate. Blow it out or blow it up is not a good design principle for recovery systems.
Click to expand...

Ok i Got a question since Im using a g64-4w reload you Got the stock black powder i bought some 4fg black powder how much would i have too stick in the cap on top of that black powder last thing aerotech told me 4fg Is the Same powder in the ejection charge?
 
wildbill126 said:
Ok i Got a question since Im using a g64-4w reload you Got the stock black powder i bought some 4fg black powder how much would i have too stick in the cap on top of that black powder last thing aerotech told me 4fg Is the Same powder in the ejection charge? Ken Allen at aerotech told me to fill cap all way up i want to do it right then kill myself lol :/
Click to expand...
 
wildbill126 said:
Ok i Got a question since Im using a g64-4w reload you Got the stock black powder i bought some 4fg black powder how much would i have too stick in the cap on top of that black powder last thing aerotech told me 4fg Is the Same powder in the ejection charge?
Click to expand...

I just use a pinch more with the G64 but remember what I posted earlier about having at least 6 feet of rail or rod. I prefer a rail cause the Gforce moves around quite a bit with a rod when there's some wind and I have used both.
 
race 58 said:
I just use a pinch more with the G64 but remember what I posted earlier about having at least 6 feet of rail or rod. I prefer a rail cause the Gforce moves around quite a bit with a rod when there's some wind and I have used both.
Click to expand...

Ya i know when i test flew it you Can see it went left would that be the Rod being little off :)

1408849940185.jpg
 
I finally got to test fly today, everything went great. Check out the photos.

ImageUploadedByRocketry Forum1408853309.883168.jpg

ImageUploadedByRocketry Forum1408853333.843968.jpg

ImageUploadedByRocketry Forum1408853345.593427.jpg

ImageUploadedByRocketry Forum1408853359.336379.jpg

ImageUploadedByRocketry Forum1408853379.246866.jpg

ImageUploadedByRocketry Forum1408853396.522835.jpg


The drogue is out

ImageUploadedByRocketry Forum1408853408.513494.jpg


Main ejection charge

ImageUploadedByRocketry Forum1408853421.956448.jpg


Main is out

ImageUploadedByRocketry Forum1408853433.816597.jpg


All the laundry stretched out!

ImageUploadedByRocketry Forum1408853444.723879.jpg

You gotta zoom to see what's happen post deployment.



Sent from my iPad using Rocketry Forum
 
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Video of the flight

[video=youtube_share;70eoPBCovKk]https://youtu.be/70eoPBCovKk[/video]




Video of the recovery

[video=youtube_share;Xbb_P34XndE]https://youtu.be/Xbb_P34XndE[/video]




Sent from my iPad using Rocketry Forum
 
Nice rockets guys!
I've got to build a G-Force one day and dual deploy would be neat.

JP
 
It's a great rocket, just make sure to remove the cooling mesh install a chute protector, and replace the aerotech clip and block with an aeropack or estes retainer so you can fly any 29mm motor. Rail buttons also are wonderful on this rocket, it's a bit too heavy for a launch rod. The quality and build design of aerotech kits are great, I definitely prefer it to plywood fins/CR's.

race, did you upgrade your Gforce to 38mm?
 
Ya i havent done that yet on cooling mesh or chute protector. I rather find one used then have to buy it :/
 
I was considering making my 38mm, but everything I read and heard said the fins could not take it, so I stayed with a 29. Next flight will be a baby H


Sent from my iPad using Rocketry Forum
 
wildbill126 said:
Ya i havent done that yet on cooling mesh or chute protector. I rather find one used then have to buy it :/
Click to expand...
Unfortunately, I don't think you can remove the cooling mesh without damaging the rocket in some way. You really don't want to install it, I've seen a few threads here about ejection failures (and witnessed one at moffet earlier this month). You could probably cut the top of the shock cord mount off and pull the mesh out, and then mount a new shock cord mount to the top centering ring using a well nut. the top plastic shock cord mount doesn't cause issues, it's the mesh only that causes most problems.

Also, I'd be careful buying a used nomex (or any chute protector) considering they get worn and burned over time.

Lowpuller, that looks like it was a great flight! What motor was it?
 
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I flew it on a a G80-7


You pull the mesh out the motor mount using a piece of wire with a hook on the end and a little patience.

I left my mesh in and used nomex wraps.


Sent from my iPad using Rocketry Forum
 
One more photo just leaving the rail!

ImageUploadedByRocketry Forum1408933553.109254.jpg



Sent from my iPad using Rocketry Forum
 
SCrocketfan said:
race, did you upgrade your Gforce to 38mm?
Click to expand...

No it's a 29mm with all the upgrades with the exception of DD but I planned for it later by riveting the coupler instead of glue and attached the nosecone with tape for now.

I plan to put her up on a baby to mid "H" next month if the weather co-operates on launch day.
 
Ya i pulled them out before with coat hanger Got too take your time i done it alot of Times too clean caps out. Thats no big deal :)
 

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