HPR noob trying to get a handle on dual deployment.

The Rocketry Forum

Help Support The Rocketry Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.
some altimeters come with test programs.....but I'm sorta lazy, so here's my test (and a good way to start DD)
1. Set up your rocket with motor ejection for your mains, but put in both apogee and main ematches. Just have your upper shock cord attached to the top of the ebay and the nose cone. Fly it on motor eject, let the nose cone eject at the lower altitude. Watch that happen during the flight. Get the rocket back and look to see if the lower (would be the apogee charge, but you have your chute in the fin can) charge fired as well. Then move your chute to the payload tube, and fly again (still with motor, it's a good backup). This time you've got the correct DD set-up AND you know it's all gonna work.....


JMHO
 
Read these:https://www.adeptrocketry.com/VCK2-VACBOTds.htm This explains the theory for you.

https://www.adeptrocketry.com/adeptQA.htm

Second one will answer many questions ya haven't thought of yet.

You can do the same by simply taping all holes in AV-bay but one....that one you will suck the air out of, either by syringe or just the "old fashioned" way.....suck it out.

This will REALLY show ya how leaky most av-bays are. Usually you will have to wrap tape around av-bay lids and coupler to get airtight fit.

Hook up Match only or X-mas mini lights, then suck air out . Release....the rest will happen on it's own.If it doesn't....ya got problems.

If ya just want to test the naked altimeter any plastic jar with screw on lid will work, make your own.
 
Thanks guys, that helps. So I guess the first time these boards actually fire charges, they will be at altitude no matter what.
 
Ematches for the charges:

I know Quest Q2G2 ones are great, but I'd like to buy more in bulk and drive the cost down. I also don't really want to get into making or dipping my own yet. Any suggestions.
 
I'm just gonna keep dumping questions here as they come to me....

When making the AV bay....is it common to glue one of the bulk plates on and leave the other removable, or leave them both removable?

I keep both ends free on my bays. I don't really see any advantage to gluing one side in but that is just me.
 
Ematches for the charges:

I know Quest Q2G2 ones are great, but I'd like to buy more in bulk and drive the cost down. I also don't really want to get into making or dipping my own yet. Any suggestions.

Get on Quest's mailing list. On their site, look for the link, "Sign up for specials". When they had a sale, I bought several bulk pack's of Q2G2's. Otherwise, they tend to be a bit pricey.
 
Ematches for the charges:

I know Quest Q2G2 ones are great, but I'd like to buy more in bulk and drive the cost down. I also don't really want to get into making or dipping my own yet. Any suggestions.

Quest has a sale once in a while and you can et their (24?48?) pack for a decent price. Honestly the price for them on hobbylinc is pretty good (89 cents per q2g2). You can get the longest e-match known to man from wildman but they are $1.50. I have not had any issues with either one and the cost certainly is affordable if you ask me.

I don't know how much cheaper you can get without dipping your own. Personally, I will use roll your own for lighting motors on the ground but I don't trust my skills for an ejection charge. It's worth the 3 bucks to me for commercially made.
 
Do they have sales often? I am on their mailing list but all I've ever seen is the Christmas 40% off sale and it had a $100 minimum.
 
I think they have sales 2 or 3 times a year but I think that all of the 40% off is $100 minimum.

Still....under a buck for a reliable commercial igniter is pretty cheap when you think about it. Granted you can get a set of Xmas lights for under a buck and have potentially 50 igniters if you are willing to put the work into it. For me, the reliability outweighs the small cost.
 
I think they have sales 2 or 3 times a year but I think that all of the 40% off is $100 minimum.

Still....under a buck for a reliable commercial igniter is pretty cheap when you think about it. Granted you can get a set of Xmas lights for under a buck and have potentially 50 igniters if you are willing to put the work into it. For me, the reliability outweighs the small cost.

I agree. The reliability of the Q2G2 is well worth the small cost of them. And think about it, the motor for my first dual deploy flight is going to be about $50. What's another two bucks for ignitors?
 
I agree. The reliability of the Q2G2 is well worth the small cost of them. And think about it, the motor for my first dual deploy flight is going to be about $50. What's another two bucks for ignitors?
Just found this old post, but now that quest igniters are more illusive than unicorns, where are you all getting igniters for DD?

Nate

Sent from my SAMSUNG-SM-G930A using Rocketry Forum mobile app
 
I recently bought some of Jim's and they work great with dual deploy, highly recommended.
 
Here is what I use for my lighters(wildman) and the charge containers caps or vials from AT reloads. Just poke a hole in the end and pull lead wire thru till the head is at the bottom ,seal with whatever( masking tape or glue) so powder doesnt leak , fill ffffg ( the amount you need for the purpose) add dog barf to fill the empty space and cap off. The Missile Works RRC2+ and sled , battery holder and switch have been very good to me.

151196483487967582940.jpg
 
Just found this old post, but now that quest igniters are more illusive than unicorns, where are you all getting igniters for DD?

There are also the MJG Firewire Initiators, which claim to be the only ones that are ATF non-regulated. I'm nearly through my first box, fortunately our local vendor carries these so I'll probably pick up another box on Saturday. I just wish they had an option for even shorter leads, even at 3' I'm always throwing a large portion away. It would appear that CTI is even using these as ignitors on the loads they've shipped since the fire (though I'm not sure if they've had any other special treatment, and maybe they just look the same, it's an assumption on my part).
 
We are instructed to put barf, wadding, and/or a nomex shield between the motor and the chute, but there is not much about what to put between the ebay charge and the chute. First time I did electronic deploy, the chute and the underside of the ebay were covered with hard to clean black stuff. I've since tried putting wadding and barf between the charge canister and the chute, that seems to help but is not perfect. Any better ideas?
 
There are also the MJG Firewire Initiators, which claim to be the only ones that are ATF non-regulated. I'm nearly through my first box, fortunately our local vendor carries these so I'll probably pick up another box on Saturday. I just wish they had an option for even shorter leads, even at 3' I'm always throwing a large portion away. It would appear that CTI is even using these as ignitors on the loads they've shipped since the fire (though I'm not sure if they've had any other special treatment, and maybe they just look the same, it's an assumption on my part).

I've started saving the excess leads for use as wiring :D
 
We are instructed to put barf, wadding, and/or a nomex shield between the motor and the chute, but there is not much about what to put between the ebay charge and the chute. Any better ideas?

Yes the answer is found in #66 of this index of my build thread:

https://www.rocketryforum.com/showt...-quot-Stock-quot-3IN-DARKSTAR-CJ-Step-By-Step

By the way it's a ["sticky"] at the top of this High Power thread. There you will find many answers to your high power questions that are applicable to any build, besides the Darkstar.
 
Wow this is an old thread....currently the Jolly Logic chute release is a good way to go to eliminate some blackpowder residue..also CO2 deployment...but also piston eject (public missiles LTD)combined with the chute release would keep your laundry clean .
 
Thanks, just ordered some from Ebay to start playing with dual deploy.

I use them more for ground testing, I don't fly DD much anymore. But when I did, I made some brass "brackets" to zip tie the tubes to, so they didn't flop around.

392_brackets.jpg

394_brackets.jpg

395_brackets.jpg
 
I use them more for ground testing, I don't fly DD much anymore. But when I did, I made some brass "brackets" to zip tie the tubes to, so they didn't flop around.
That's a neat and logical alternative to charge wells / cannons when using vials. Nice one!
 
Back
Top