Sneak Peak: Jolly Logic's Easy Dual Deployment

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Do me a favor... Post pics of your packing technique for those 38mm tubes!

Will do.........................once I dial it in myself.

Like I said, it's going to take some VERY careful and creative technique. I can see that it can work, but I'm still figuring out the best way to accomplish this.
All I've done so far is to see if I could stuff it all in there, and yes I could, but it was by no means something I felt I could rely on just yet. What I had was a very tight fit but also some airspace around it, which would very likely result in the nosecone ejecting but the CR and chute bundle refusing to come out. So, while I can see that it's possible to make work, I still have some fussing around to do before I feel I can fly and rely on it. I'll keep you posted. In the meantime, anyone else who gets it dialed on their own, I would also love to see how they did it.

s6
 
Anyone have an idea of how big of a rocket this will work in? I'm building a 4" Madcow Sea Wolf that'll end up being around 85-90 ounces. Will that be "too big" for CR to handle?
 
Anyone have an idea of how big of a rocket this will work in? I'm building a 4" Madcow Sea Wolf that'll end up being around 85-90 ounces. Will that be "too big" for CR to handle?

I flew it in a rocket that was a bit over 40 oz on a G57 and it worked fine. I think the weight of the rocket ultimately doesn't matter much if the chute is bundled well, as the CR doesn't handle any of the shock loads. If you are concerned about descent rate before the CR opens, adding a drogue on the shock cord can't hurt (if you balance the location so the nose/booster don't collide).
 
I honestly don't see any reason that it wouldn't work in that situation. It's really a question of the size of the parachute. The CR is meant to be used such that there is no load on it from the rocket itself, the shock cord, etc. The only load it bears is from the band that goes around the chute (if you use it correctly). So, as long as the chute bundle can be held intact via the (pretty stout) rubber band, than the CR should work just fine. It should certainly handle any size chute you would use for that rocket.

s6
 
Anyone have an idea of how big of a rocket this will work in? I'm building a 4" Madcow Sea Wolf that'll end up being around 85-90 ounces. Will that be "too big" for CR to handle?
I built that rocket last Nov. with the specific intention of using CR with it.
111815_Sea Wolf_Comparison.jpg

I'm waiting for some decent weather so I can clear coat it before I launch it...
 
Sounds good. I was hoping that would be the case. I might just use my Sea Wolf to certify L2.
 
Just ordered mine for use at my next launch. I can't wait to try this - it's just a superb idea.
 
I flew a LOC HIGH-TECH H45 on a CTI H151 RL and a CTI H225 BS H last Sunday at the SARA launch and the Chute Release worked perfectly.

Nice packaging, easy to use, a durable have already been said here. Mine arrived in 48 hours direct from Jolly Logic. The only thing to add is that I will need to order at least one more.

A couple of months ago, about the time I started reading this tread, my orange fiberglass 68" tall 38mm minimum diameter DD rocket called the Clementine core sampled. I was left with the nose cone housing a BRB 900 tracker and most of the lower body tube and Acme fin can. With the arrival of the Chute Release I'll try flying the Clementiny at the February SARA launch.

The main issue I had packing the chute for a 38mm diameter rocket was the friction of the rubberband included with the Chute Release.
This morning I picked up some hammer snap fasteners, a snap fastener tool and some 3/8" braided elastic from a fabric store. The snap fasteners are too wide to fit through the slot on the Chute Release body but the "outie" one fits through the ring on the Chute Release pin. Then snap the fasteners and loop it through the Chute Release like you would with a rubber band. The final packed assembly is lower profile and has less friction than with a rubberband. The finished pack will slide out of the tube just holding it upside down. The chute pictured is 28". From experience with Cable Cutters I banded the shock cord together with the chute to prevent any stress on the tether for the Chute Release.

Here are images and an instructional video I found for installing snap fasteners.

Kudos to John Beans for an excellent product .

1CRMOD.jpg
2CRMOD.jpg
3CRMOD.jpg
4CRMOD.jpg
5CRMOD.jpg

[video=youtube;b19t845GuJs]https://www.youtube.com/watch?v=b19t845GuJs[/video]
 
Miles, that is some excellent work. Very nicely done!

I love seeing techniques like this.

During the development of Chute Release (which evolved a lot from its first iteration to eventually settle on using bands), I experimented with a lot of bands and straps. Yours reminds me of one of the ones on my bench, which is an elastic fabric strap that is adjustable. I haven't gotten it quite right yet (cost, adustability, durability, manufacturability), but you're inspiring me to keep working on it so that we can expand the collection we offer to everyone.
 
Received mine today. Charged it and tested it, and now I really can't wait to use it in anger.
 
Miles,
Those were nice flights.
How did you protect the parachute-chute release bundle from the ejection gases?
Ken

Just a piece of nomex wrapping the chute and Chute Release. Lots of room in the LOC High-Tech H45. For a 38mm tube there is no room to wrap the whole bundle in nomex, some a small patch of nomex and maybe some dog barf. I'll ground test first.
 
Question for John. Is it neceesaary to have air holes in the BT for the Chute Release?
 
Question for John. Is it neceesaary to have air holes in the BT for the Chute Release?

I'm not John, but the answer is yes.
It needs pressure sensing capability to know that the rocket has left the ground before triggering the release on descent
 
I'm not John, but the answer is yes.
It needs pressure sensing capability to know that the rocket has left the ground before triggering the release on descent

I'm not John either, but make sure the holes are big enough! I drilled too small of holes when I first started using my AltimeterOne, and it threw off the readings, like the pressure (ok, vacuum...) was not correctly compensated.
 
Question for John. Is it neceesaary to have air holes in the BT for the Chute Release?

No, vents aren't really necessary for Chute Release under normal conditions. The logic (discussed in the User Guide) is that Chute Release needs to be over 100 feet for a while, then it needs to detect falling for a bit, then it opens once the release altitude is reached. It would take very unusual circumstances for that not to work correctly even if the fuselage is airtight.

You could imagine a scenario where your rocket arcs over and heads towards the ground and ejects very very low. In an airtight fuselage, Chute Release wouldn't have time to open before it plows in. If your fuselage was vented, however, Chute Release will have released by then so it would act like a regular parachute upon ejection. Not that the result would be pretty, but the parachute would open probably. That's an extreme case.

If it were me, I'd want to be flying a recording altimeter like AltimeterThree as well, and that needs holes to get real-time readings. If you've seen the graphs AltimeterThree creates on your phone, you can see how handy it would be to immediately know how long it took your chute to release and unfold. For instance, if you set it at 400' and it was at landing speed by 350', you would know that your folding resulted in effective slowing in 50 feet. So then you could be comfortable flying that configuration with a 200' setting for instance.

Everybody flies with different goals and approaches, but for me I like the option of putting an oversize (read: soft landing) chute in my rockets, and opening it up low (so it doesn't drift far).
 
I should also mention that having vents makes it harder to "spoof" Chute Release when you play around with the nosecone (pulling it on and off) on the pad. I tried to make it ignore normal handling like that, but if you tried really hard on an airtight fuselage you could probably slow-w-w-ly pull the nose cone off and make it think it was flying and cause it to open on the pad. Not a disaster (the parachute will open right away upon ejection) but you won't get the benefit of delayed release in that case.

So vents could be considered a good preventative practice. Belts and suspenders.
 
Well today at the LUNAR launch, after seeing the flights other people were doing with the Chute Release, a friend and I broke down and bought one to split. Luckily it came fully charged, so I was able to test it with one of my rockets. I did two ground tests with it, and both worked perfectly. I then put it in my Madcow mini Tembo, which is a 38mm airframe, loaded up a G64-7 now that I wasn't worried about drift, and let it rip! The chute came out and stayed bundled, and released at what looked like 500 feet, which it was set to. Then it landed about 400 yards away, which was way better than what it would be without it. After that one flight I am sold on it, and will now probably use it on any flight that it will work on. And to provide input on the question above, the rocket did not have any vent holes.

Awesome product John!
 
I bought one as well at the LUNAR Snow Ranch launch this morning. Mike from Bay Area Rocketry said he'd brought a box of 10 to the launch. I bought #5 and don't know if anyone else bought one or more after me.

Looking forward to successful "dual deployments" using rockets with no altimeter bays as I'm geezerly and don't much care for those long recovery hikes over hill and dale.
 
I flew mine today and it released at the 600' setting near the end of the line of cars, away from the launch racks, and my rocket unfortunately landed in the creek. Now my chute release doesn't work. I opened it up to dry it out and tried to disconnect the battery but I broke the connector. Will be ordering a new battery in the hopes that the chute release will work once it completely dries out.
 
Best way I know of drying out electronics is to use those desiccant packs that are packed in everything you buy these days. I collect and store them in large glass jars.

Drop your drowned electronic device into the jar or into a zip-lock baggie filled with the packs and leave it there for a day or two. I've also used this method to dry out cardboard rockets that have tried unsuccessfully to swim with excellent results.

I've heard uncooked rice will work as well.
 
Best way I know of drying out electronics is to use those desiccant packs that are packed in everything you buy these days. I collect and store them in large glass jars.

Drop your drowned electronic device into the jar or into a zip-lock baggie filled with the packs and leave it there for a day or two. I've also used this method to dry out cardboard rockets that have tried unsuccessfully to swim with excellent results.

I've heard uncooked rice will work as well.

+1 on the uncooked rice.
 
+1 on the uncooked rice.

I heard a joke along those lines of what the rice is -actually- for..but...I just can't....not here.

But +2 on the rice... My ex wife had had her fancyfone dropped in a 5 gallon bucket of water, submerged for at least a half hour, and the bag of rice trick actually worked.
 
I flew mine today and it released at the 600' setting near the end of the line of cars, away from the launch racks, and my rocket unfortunately landed in the creek. Now my chute release doesn't work. I opened it up to dry it out and tried to disconnect the battery but I broke the connector. Will be ordering a new battery in the hopes that the chute release will work once it completely dries out.

Why don't you mail it to me and let me check it out? Address on Jolly Logic website under support. I'll make sure it's back in fighting shape. Be sure to include your return address.
 
I flew a Chute Release flight at the LUNAR Snow Ranch launch as well, and it worked great. An H399-9 in my 29mm powered BAR Crayon boosted very quickly to 1939 ft and ~40 g's, and motor deployed a 12" drogue chute attached to the nose cone. At 500 feet the CR opened and by ~400 feet the bundled 48" Spherachute had fully deployed for a nice soft landing about 500' away. Perfect flight and I can't wait to fly it more!

It was great to see the number of Chute Releases in the field at LUNAR yesterday. It seems like it was half of the flights! There had to be at least 8-10 flights, and it looked like all deployed right on cue. Jolly Logic has a great product here and it definitely works up through high power. I'll be using this for dual deploy on several rockets now, and can't wait to try some larger rockets and motors.

Here's the flight graph from the A3. The rocket landed on a hill, so it recorded about 2 minutes of extra flight data, so I'm also attaching a screenshot of the Excel output of the flight. Look at the change in descent rate at ~400 ft thanks to Chute Release!
CR_H399_2.jpgCR_H399_1.png
 
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Why don't you mail it to me and let me check it out? Address on Jolly Logic website under support. I'll make sure it's back in fighting shape. Be sure to include your return address.

That would be fantastic John. I will send it to you post haste; I already ordered a new one so when this is fixed, I will have a back-up. I could have used that back-up yesterday :smile: I will include the battery too; perhaps the connectorcan be replaced too and save what is a once used battery.
 
Here's the flight graph from the A3. The rocket landed on a hill, so it recorded about 2 minutes of extra flight data, so I'm also attaching a screenshot of the Excel output of the flight. Look at the change in descent rate at ~400 ft thanks to Chute Release!
View attachment 281795View attachment 281796

Benno, glad we gently delivered that crayon. (Benno was a beta tester, and last time this combo flew we still had the 12.5 minute bug, so it bounced off the turf at October Skies.)

Tip: when you get "extra data" like this, tap the last point on the graph you want to include (it will show then as a big blue dot), then click on the marker/flag icon in the toolbar, and click Flight End. That way the graph will just show the good bits (the data isn't deleted, just hidden). It will also automatically set the Data End (for the spreadsheet) though that's also separately adjustable.
 
I know I should have bought a replacement unit from Mike at BAR, but, at the time, I hadn't decided I needed a replacement. However, by 7 p.m. last nite, I decided I needed one and ordered it from Amazon. At noon today, the USPS delivered it to my front door. That's 17 hours from time of order!
 
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