Chute Release - Questions, Tips, & Issues

Being one of those who just received Jolly Logic's new Chute Release device, I thought I'd begin a new topic for use questions, user tips, or potential issues.

In another place comments have been made regarding the small buttons - easy to use for some, for others with 'stubby' fingers no so much. My resolution is to use a small piece of 1/8" dowel as a depression tool.

Next item is chute folding tips. The user manual (pg 7) notes there are some on the Jolly Logic website, but I've not found them. Perhaps John hasn't yet had the opportunity to post them?

Last item is a general use question. Is there any real disadvantage to testing and then prep'ing a rocket a week before a launch? In cold weather fingers and small parts don't always work well together, so doing the setup & prep ahead of time would be handy.

None of this is meant to suggest any real problem with CR, but I think it's worthy of discussion...

Prepping in advance with the cold will depend on your chute material.
If you are using a plastic chute like from Estes, the cold will make them stiff and they won't open. When I fly when it is cold I keep those chutes in an inside pocket to let my body keep them warm and only take out and pack just before flight
If you have nylon chutes this is not as big of a problem, but still may depend on if they are thin mil or not - again you need to judge based on past experience with your chute material and its stiffness in the cold

John responded to my comment regarding the use of a small dowel on the NAR FB page that I thought should be noted here...

Do *NOT* use any hard item like a dowel to press the buttons. They will dent. Instead, just mash them hard with your finger.

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Fortunately I did not get the chance to use my "tool" and based on John's reply, I won't...

If you're having trouble pressing the button (btw - I had trouble until I used my pinkie), how about keeping a spare igniter/starter plug or two in your pocket to push the button? IMHO it's not too hard nor too soft and you should have some on hand. I think the white D size ones would be good.

My advice would be to put your finger on it and just mash down really hard. It's not like you're going to crack that case.
I know it doesn't look like a typical button, but it's supposed to be impossible to accidentally hit, yet still press-able.
So it has a distinctly different tactile feel from, say, our other altimeters (which are very clickable).

If it ends up being a major issue for folks, I'll look into changing the button in a future production run.

I've got enough meat on my fingers, that with a little pressure, they will press the buttons. It took a little practice to learn consistant pressure.

Operational, I've tested mine quite a bit, and, occasionally, the servo pin (?), that engages the release pin, will not drop back down enough to properly lock the release pin in place. When it happens, a slight wiggle of the release pin will allow it to drop down and engage.

Apologies if this has been answered elsewhere, but is there a minimum operating temperature?

Here are a couple of pics of the occasional issue I mentioned. First one is with the pin down, as it should be. Second, is with it stuck up, not catching the release pin. Like I said, frequency has decreased with continued testing, and, when it happens, a wiggle of that cylinder will allow it to drop into place.

Would pressing the button with the eraser end of a pencil be acceptable?

John Beans said:

My advice would be to put your finger on it and just mash down really hard. It's not like you're going to crack that case.
I know it doesn't look like a typical button, but it's supposed to be impossible to accidentally hit, yet still press-able.
So it has a distinctly different tactile feel from, say, our other altimeters (which are very clickable).

If it ends up being a major issue for folks, I'll look into changing the button in a future production run.

Click to expand...

I say try the pinkie!

BTW - Big :clap: to you John for such quick shipping...WOW! I ordered on Tuesday night and got it Friday...CA to NY in record time I think!

wighty44 said:

Is there any real disadvantage to testing and then prep'ing a rocket a week before a launch? In cold weather fingers and small parts don't always work well together, so doing the setup & prep ahead of time would be handy.

Click to expand...

I had a situation awhile ago with a new nylon chute that had a slightly tacky feel to it, and I was using a deployment bag and packing firmly. Fortunately during ground testing I discovered that if it had been packed for over about 12hrs the gores would stick to themselves and it would only partially open. Washing the chute and coating it with talc helped but I couldn't get it to open consistently enough during testing so it got retired. I haven't had this issue with any other chutes however thought it was worth a mention if you are planning on packing chutes well in advance.

Looking at the tether it appears to be made of a thin, braided, colored material - perhaps Kevlar? It occurred to my that there might be time when a longer tether may be needed. I have some 380 Lbf, 1/16th inch, braided Kevlar that should do that job quite well.

Take note that it is the release of the button after you press that initiates the action, NOT the press of the button

wighty44 said:

Looking at the tether it appears to be made of a thin, braided, colored material - perhaps Kevlar? It occurred to my that there might be time when a longer tether may be needed. I have some 380 Lbf, 1/16th inch, braided Kevlar that should do that job quite well.

Click to expand...

Yep, that'll work great.

Swissyhawk said:

Would pressing the button with the eraser end of a pencil be acceptable?

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Probably be okay, since it's soft, as long as you don't apply more pressure than necessary. But not as convenient as a finger.

asheriff said:

Apologies if this has been answered elsewhere, but is there a minimum operating temperature?

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The battery would be the main factor, and during discharge it's rated by my battery supplier from -20C to 40C.

If I were you, on a really cold day I'd just keep it in my pocket when not flying, and then mount it and use it just prior to walking to the LCO table or pad. Probably unnecessary, but just as a little performance booster.

In the past, we've had LCD displays that would stop responding in the freezer, while the batteries continued to operate. I'll toss one in the freezer and verify later that 0C is okay.

Thanks John. I left mine out in the garage overnight and it worked just fine in the morning. Probably 20F.

I froze one for a couple of hours, and even though it released, it was obvious that it was not as peppy as it was after warming up for 5 minutes.

So I'll put an advisory on the website to keep them from prolonged freezing temperature exposure prior to flight.

Got a bunch of ground tests on mine now. Some folding advice that has worked for me: However you fold your chute, make sure you fold it in a way that the lines are folded over at least once inside the parachute. If they are not, when you pull on the shroud lines, they'll just slide out of the parachute.

My thoughts on the unit without having flown it: Holy crap! Even the packaging is nice! The case seems extremely durable. I see a second in my future for redundancy in larger rockets. As far as the button goes, I use my pinky finger nail to depress the buttons. Works fine for me, as I do it pretty gently. I especially appreciate the countdown the unit goes through when you do a ground test.

I thinking of wrapping my chute in a chute protector and putting band around the whole thing. How do you guys think that will work?

crossfire said:

I thinking of wrapping my chute in a chute protector...

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I would think you'd also want to protect CR as well as the parachute from the ejection discharge heat and particles. Wrap both the chute & CR inside the protector.

crossfire said:

I thinking of wrapping my chute in a chute protector and putting band around the whole thing. How do you guys think that will work?

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Gary, I wrapped my chute, banded that, then wrapped the whole thing in Nomex. That way the device is protected, too. Also, I usually wrap a few lengths of shock cord in the Nomex, as well. If I wrap the Chute Release around the whole bundle, then the rubber band is actually holding some stress of the shock cord instead of just the chute.

Can't wait to get this! Thanks John for such a cool device & the free shipping! I can see getting a 2nd one soon.
I did not see Extra Bands available on the Jolly Logic website. Coming Soon?

I could see where the situation calls for 2 flame blankets. It comes down to factors like altitude setting of the CR, apogee altitude, pack volume of chute, AF compartment size, inflation characteristics of chute being used....
Maybe on a large bulky chutes like the Aerocon's or other mil surplus chutes you could use 2 CR's....one at each end of the pack job?? Yikes! I'll try it.....someday....

This is how I packed a 18" parachute to slide cleanly in a 38mm body tube. It appears to work according to ground tests. I used a long rubber band and went fully around the chute before securing it.

Tonimus said:

This is how I packed a 18" parachute to slide cleanly in a 38mm body tube. It appears to work according to ground tests. I used a long rubber band and went fully around the chute before securing it.

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Are you sure those shroud lines won't pull out of the bundle? Maybe try spinning the chute to see what some tug will do.

I'm pretty sure. I swung the heck out of it. The lines run up and over the top of the chute release, and back down the other side.But even if they do, the chute will still be rolled up and reefed. As a bonus, if I attach the chute release to the shock cord at the same point as the parachute, it can only pull out about an inch. I couldn't get a good pic, but I put 8 pounds on the chute with no movement before I was wary of any more pressure.

I use a ball burnisher for many purposes in rocketry. A tiny one can flip the dipswitches on your MW altimeters, align your #2-56 shear pin holes, and, although I haven't tried it yet, most likely press your Chute Release buttons.

I inherited one years ago. If you Google "ball burnisher for paper", you can find some. They are cheap (~ $3 = $10). Also known as an "embossing stylus". Amazon has them.

Love seeing the folding photos!

1. The button is deceptive: it looks like you need to get in there and just press the brass center. But please try to just press your big giant finger over it and mash down hard until it clicks. Please just try that a few times. Please?

2. Chute Release is built for punishment. I'm not claiming it is completely unbreakable, but you could drive your car over it. I'll give you a fee replacement case if you ever need one. Worry primarily about protecting and deploying your chute.