Chute Release questions

The Rocketry Forum

Help Support The Rocketry Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.

qquake2k

Captain Low-N-Slow
Joined
Jan 26, 2010
Messages
13,574
Reaction score
65
I have a few questions about the Jolly Logic Chute Release. Has anyone ever lost the pin because the rubber band broke? Would it be a good idea to tether it with a length of Kevlar thread, or would that be a chance for a tangle? For that matter, could you use a length of Kevlar thread tied across the parachute instead of a rubber band? How rugged is it? Would it stand up to a lawn dart or core sample? I ask this because I recently demolished a 1st gen Altimeter One in a core sample accident. I'm ready to purchase one, I think it's a game changer in our hobby. But I guess I just need a little encouragement. $130 would buy a lot of motors (at least the kind I fly).

altimeter_one.jpg
 
I've seen the chute release survive a few bad bumps...
Even a no separation at apogee from the motor..
I think it's quite robust Jim...
Even the Alt 1 you broke up must have taken quite a shot....
They're flown so much these days their record is fantastic...

Teddy
 
It seems like every other flight I see at club launches these days has a Chute Release in it. I sure do like the idea.
 
lol..
Me too..
This is the single greatest advance in rocketry's history as far as I'm concerned..
I tell people it's almost cheating..
It replaces the av bay, wiring, batteries, switches, bp charges, e matches..
That's w hole lot of possible fail points to be replaced by this one unit..

Teddy
 
Only if you're flying with a motor that has an ejection charge! Try that with a Loki 54mm!

ha,,,
There are 10,000 ways to fly it and it's super easy to set up and works perfect,,
you have to find a way that's difficult to cite...
Grind out the forward and make a bp well in it,, lol..

Teddy
 
If you're going to Gibson ranch next weekend feel free to try mine before you buy one. Although after trying it I'm sure you'll want to buy one.
 
If you're going to Gibson ranch next weekend feel free to try mine before you buy one. Although after trying it I'm sure you'll want to buy one.

Yes I am going to Gibson Ranch, and I appreciate the offer. But I think I'll go ahead and order one.
 
I have had 5 perfect flights with the JLCR and 1 failure due to rubber band breaking and I did lose the pin. I just have extra pins. Yes it should work out to tether the pin.
One just needs to inspect the band before each flight. When I lost the pin I had chute all wrapped and ready for fight the night before. So thinking the band was stretched for to long of a time and broke.
 
Last edited:
I had a lawn dart at the last launch with my Wildman Sport. The chute release survived unscathed and passed three bench tests afterwards. The Altimeter 3 was toast though, looked a lot like your Altimeter 1 there. My lawn dart was due to my RRC2+ losing power under boost. Or that is what we diagnosed. Had a piece of sled catch the battery clip but not the battery. Barely broke connection but it was enough.

I use my chute release in all flights that isn't dual deploy. I use an altimeter to pop at apogee and the chute release to pop at 500'. The Wildman Sport coming in hot with no apogee event suffered less damage (only damage was clear coat came off nose cone) than it did when it deployed early. I have had bad experiences with delays so all my flights use altimeters at apogee.

Tethering the pin to the chute release itself should work fine. In fact I think I will do that. Added to TO DO list.

The chute release is used on a lot of flights at our launches too. Awesome product and awesome customer support.

Mikey D
 
Last edited:
I recently ordered an Altimeter Three to replace the One. I got a neoprene USB drive case that will hopefully protect it.

case02.jpg

case03.jpg

case04.jpg
 
I don't use my rubber bands to the point that they have any cuts or wear on them. Haven't had one break on me yet. Jolly Logic does offer an accessories pack with extra bands and pins. Shortly after I got the CR, I had it in my 2.6" Black Brant II, but the parachute didn't make it out and it core sampled. After cleaning out all of the dirt and mud, I noticed the CR had in fact still let go of the chute. Of course, it didn't know it was still in the rocket. It was an undersized ejection charge that failed to get the laundry out. Chute Release took it like a champ and still flies at every launch I go to. ImageUploadedByRocketry Forum1492309453.194939.jpg
 
Yes,, this all sounds pretty common to me...
Every launch you go to there are chute releases flying...
For the most I hear positive things about them..
I don't know why Mark had seen otherwise,, maybe just luck I guess...
In any event ( get it,, event,, get it,, aw ferget it..) all Jolly Logic products ship for free from me....

Teddy
 
Out of how many CR flights?

I have seen this a couple times, and a few other issues.

Conversely, I have seen others have great success.

I am sure there is a certain technique to it, but what is I cannot say.
 
In my lawn dart the chute release was open as well. We had 2 fail to work properly that day, causing a near total loss on one rocket, and was kinda "a bad day to be trusting the chute release" attitude. I joke that mine opened at least. Even though my rocket didn't. Not sure why they failed to open. I did hear once conversation about how one successful flight was packed/wrapped different than the KO. I have seen failures caused by the chute getting tangled. The chute release was open, the chute just failed to deploy.

Mine even hung on a power line all night. Beating around on the nose cone from the wind blowing the chute. The things are tough. Just wish my Alti3 would have been that tough. No worries on that though, Mr Beans helped me out there.
 
The chute release comes with extra bands and pins.

My one failure was when the shock cord wrapped aound the chute bundle but the CR had in fact opened...the drogue saved the day. Through recovery train experimentation I have discovered a set up that works reliably with my particularly troublesome rocket (an L2 Polecat Aerospace Goblin 5.5). All other rockets have worked properly.

Use common sense and allow sufficient release altitude for a stubborn chute to fill. Setting an HP rocket to open at 200' is tempting fate. 700' is my HP rocket minimum.
 
I don't own one (It's still a little pricey for a BAR that only really builds/flies LPR/MPR - That $$ can buy a lot of kits and motors at HL with a 40% Off Coupon)... So I can't speak from specific experience, but I would think that adding a lanyard of #100 Kevlar to the pin certainly couldn't hurt. I would make the lanyard equal to the length of the maximum stretch of the rubber band, plus maybe an extra mm or two. That way, if the rubber band broke, not only would you not lose the pin, but you'd potentially still keep the chute trapped until it was programmed to release.
 
Tango

When you finally break down and buy one, and you will, you will be asking yourself "Why didn't I do this sooner!"

It opens up a world of options and let's you fly'em high and fast.

Only current down side is sizer, it won't fit in a lot if smaller rockets, but I suspect that will change in the very near future.
 
Tango

When you finally break down and buy one, and you will, you will be asking yourself "Why didn't I do this sooner!"

It opens up a world of options and let's you fly'em high and fast.

Only current down side is sizer, it won't fit in a lot if smaller rockets, but I suspect that will change in the very near future.

You're right... Eventually I will. :wink: I also read that there is a smaller one on the way, just probably not before next Winter. Maybe by the time I get my Ventris SRB project completed I'll break down and buy one.
 
Use common sense and allow sufficient release altitude for a stubborn chute to fill. Setting an HP rocket to open at 200' is tempting fate. 700' is my HP rocket minimum.

I agree 200ft is too low. But 700ft might be too high. I'll probably go with 500ft. What's the worst that could happen? LOL
 
I routinely use the CR set at 300ft with 2.2, 2.6 and 3" rockets. Check the rubber bands for wear and fold chute as directed, never had a problem. Comes with extra bands and pins.
 
I routinely use the CR set at 300ft with 2.2, 2.6 and 3" rockets. Check the rubber bands for wear and fold chute as directed, never had a problem. Comes with extra bands and pins.

Absolutly + 1.....
It really is up to what type of chute you use and how you fold / pack it up...
Ever notice how some guys get their chutes to inflate quickly and some are more hit or miss,,
no matter whether from an e charge deployment or a chute release...
There's a reason for this....

Teddy
 
I've always used the relatively unrecommended roll method with the shroud lines wrapped around the chute. Never had a problem. My chutes always open pretty quickly.

[YOUTUBE]ICIk50mxalc[/YOUTUBE]
 
I had a band break once, though I'm pretty sure I know why. I've always tried following John's technique of folding the shroud lines inside the chute, but that particular pack I think things were loose enough inside that when things started to pull in air the strap tried to pull the CR further up the chute, and broke the band in the process. So the main came out at apogee, and when I recovered the rocket the band was broken and the pin was missing (so it clearly released at the appropriate time). John sent me a replacement pin and a long piece of the cord, I've been intending to both make a longer loop for the CR attach itself, and considering the rest of it to make a 'backup loop' to hold the pin in case the band breaks (just so that I don't lose the pin), but I am a bit afraid that this extra loop could create a tangle, so I haven't actually done it yet. I do now do a final 'tug' on everything to ensure that the shroud lines are taught with there still being slack on the CR's strap before I wrap my chute protector 'burrito'.

I had a second flight (most recent Snow Ranch) where I thought the band had broken again, the main was out at apogee, but when I recovered it the band was intact. I continue to have terrible luck with AT motor ejects, this was an undrilled J180T-L where the motor charge went off at 6.8s after burn-out instead of the expected ~14s, and I guess the early ejection pulled the chute out of the band without breaking the band, unless it somehow tricked the Chute Release into releasing early. Either way, no parts lost (and I've flown that band 3 more times already), just an early main parachute deployment, leading to it spending about 4 minutes in the air and landing about a half-mile away, still easily found thanks to an Eggfinder TRS.

But lots of other totally successful flights, including two more yesterday on my Nike Smoke, a J401FJ and a J1520VMax, both flights to ~4800' with the main releasing at the expected 500' and short walks even though it was pretty breezy at ground level.
 
Last edited:
The only CR failure I've had was when dumb ass (me) forgot to turn it on:facepalm:

The JLCR does come with several extra rubber bands of various lengths under the foam packaging. There are also extra tethers and pins.
I have found that daisy chaining two rubber bands together for larger chutes takes some of the strain off the bands and still holds the bundle tight enough.
 
I recently ordered an Altimeter Three to replace the One. I got a neoprene USB drive case that will hopefully protect it.

Don't you think it might strip in the slipstream on descent? Maybe duct tape over that hole?

Lost pins? Mr. Beans has more. Ask him. Don't put too many pieces of kevlar string near the device as there is the risk it could tangle the whole assembly.

I've had 3 failures. One where the whole assembly fouled with the harness and two where after ejection the chute protector didn't fall away from the CR/chute. The Chute Release did its thing but the stiff chute protector kept everything closed!
I remedied that by affixing the chute protector on the harness with a little distance between the chute protector and the packed assembly. There's a slack bit of harness between the protector and the chute pack. When the ejection occurs, the chute protector is pulled off the packed chute assembly and is out in the breeze completely. I've done this and it's been 100% so far on the next three flights.

I didn't count the smoky burnout rocket:
burnout.jpg

Forward closure failure. When seeing two colored plumes on liftoff, that's trouble! Rocket was only up maybe 200 feet and tumbling. Charge blew and the Chute Release immediately released but there wasn't enough altitude for the chute to fill. Another 50 feet and it might
have made it. Rocket was repaired with a coupler I painted black so it now flies with what looks like a hole in the side. FG rockets can take a beating with soft farm ground to hit.

20160617_185539.jpg20160617_185333.jpg

Though the kevlar cord looks ratty, it's still plenty strong. The forward cutting plume of propellant came out about 180 degrees on the other side and the Dino shockcord protector which I had encased in a sleeve of the Borate/Boric acid soaked "fireproof" cardboard via duct tape took the brunt of the heat:
pic3.jpgpic2.jpg

Just flipped the Dino protector around as there was a little "melt" injury on the end closest to the forward closure but still a lot of life left in it. Rocket has had four successful flights now with a GPS tracker and Chute Release. Go soak yourself some cardboard in
borate/boric acid fire proofing solution. Can be cut in strips to "protect" a chute protector and can also be used as a divider between a harness and the ejection flames. The end can be folded 90 degrees to help blunt a flame front. Since one can size it to fit loosely it's helpful and cheaply disposable when blown out of the rocket at ejection time.

Kurt
 
Last edited:
Back
Top