School me on cable cutter, ematch, altimeter options

Looking to get into relatively easy dual deploy on some MPR kits.

I am looking at the Archetype cable cutter now sold by PrarieTwisters.

Where would I get the ematches?

What would be a good cost effective altimeter, or one I can switch around to different rockets?

All info welcomed as searching each topic gave almost too much info rather than specific info I need.

Thanks!

Lots of places for ematches (including E(vil)bay). Get in touch with Crazy Jim here on the forum.
Great, cost effective altimeter? - can't beat the Missileworks RRC2+.

Cable Cutters are great kit, but do keep in mind that many folks need to experiment a fair bit to get their particular methodology down for reliability.

s6

I have two of those cable cutters. While they serve their purpose I've run into a couple of issues: they're difficult to disassemble after use, and more than once the main has not come free during the fall despite the zip tie being cut. I haven't really gotten it down to a science yet so I only use it on my really light fg rocket that descends slow enough under no parachute that it isn't going to hurt anybody. Try and find ematches with smaller and shorter heads as the big ones don't fit well.

I have not yet jumped into DD, but if I were to, I would seriously consider the new Jolly Logic Chute Release.

It seems by the time you buy the deployment computer, e matches, black powder, build an AV bay, backyard testing, etc, it seems the Chute Release would still be less expensive.

Does anyone concur?

McKailas Dad said:

I have not yet jumped into DD, but if I were to, I would seriously consider the new Jolly Logic Chute Release.

It seems by the time you buy the deployment computer, e matches, black powder, build an AV bay, backyard testing, etc, it seems the Chute Release would still be less expensive.

Does anyone concur?

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No experience with cable cutters, but I too am interested in the Jolly Logic chute release system. As for altimeters, I have a PerfectFlite Stratologger. But now they have made it smaller. I like it a lot. Here is link to it's page.

https://www.perfectflite.com/SLCF.html

I have use cable cutters with 100% success in limited flights (3).

I cinch the cable tie very tightly so that the parachute tends to pop out when the tie is cut. It still takes 1-2 seconds, though.

I use Quest Q2G2's to fire the cable cutter. I use a bit more than the recommended 0.1g of 4Fg powder. I have a hard time measuring that small of an amount, so when I'm close / slightly over, I use that.

The altimeter I use is the Adept 22.

I'm a bit nervous about having that length of wire wrapped around the shock cord, but I have plenty of excess to account for it. As I said, in limited trials, so far, so good.

I have bought the chute release product and am waiting on good weather to fly it. It solves several of the basic dual deploy problems for me:

Less hazmat: This is really the big one. I didn't see how to do dual deploy without adding either black powder or a homebrew hot wire system. I don't really need another thing that goes foof or bang in my garage.
Reliability: It's a commercial product and I'm pretty confident it's been tested pretty thoroughly. I don't especially want to home-brew.
Portability: I can loan it to someone else, I can swap it in and out of my rockets, my daughter's TARC team can borrow it for testing. How often can you loan dual deploy to someone?

If you've invested nothing at this point, I'd have to recommend the Chute Release from Jolly Logic as well. You will still need to rely on motor ejection at apogee for seperation, as opposed to using altimeter based seperation. Weight gain will only be .6oz, and, the only modification needed is a small pressure relief hole.

f you go the cable-cutter route, the absolute cheapest deployment altimeter is the Adept DDC22. It does not log anything, nor tell you the altitude reached. It just sends a current at apogee and/or preset altitude as desired. You can have one in your hand for about $41.

I just purchased Chute Release but haven't tried it yet. As others have said, same exact function, no e-matches or black powder required. Easily moved from rocket to rocket.

Bat-mite said:

f you go the cable-cutter route, the absolute cheapest deployment altimeter is the Adept DDC22. It does not log anything, nor tell you the altitude reached. It just sends a current at apogee and/or preset altitude as desired. You can have one in your hand for about $41.

I just purchased Chute Release but haven't tried it yet. As others have said, same exact function, no e-matches or black powder required. Easily moved from rocket to rocket.

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However if you can solder a Eggtimer Quark kit is a $20 altimeter. I like my ematches, BP, and stuff, however I will eventually buy myself a Jolly Logic Chute Release.

Looks like the jolly logic route for me. That about takes care of everything. I tried to buy BP the other week in anticipation for cable cutters and ejection charges etc.. wasn't a good experience.

Rob702Martinez said:

Looks like the jolly logic route for me. That about takes care of everything. I tried to buy BP the other week in anticipation for cable cutters and ejection charges etc.. wasn't a good experience.

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Whoa, what happened?

Bat-mite said:

Whoa, what happened?

Click to expand...

When I bought BP, I am now on 'The List'...Big Brother -knows- I have it.

Though I obviously don't have malicious intent, the fact that I had to give all my personal information just to purchase it kind of irked me..

You should have asked here, what to do to buy FIRST...before going to a store!

Never...ever..mention BP is for rockets.

A very simple solution is what I always do when asked. "It's a birthday present for my cousin. He hunts using a muzzle loader."
Don't know what kinda rifle....his wife suggested I get him some.

Never fails.

Last spring when I purchased, they called over the manager. After the normal questioning, I asked why.

"Last week we had a hokum come in wanting 25 lbs. When asked what for...he replied ....for pipe bombs... now in prison awaiting trial.

So ya see there are idiots out there after all. Stores have tightened up security immensely & I don't blame them. If you put there mind at ease, you will not have issues.

Yea It didn't occur that it was such an issue as I see it for sale all the time. I know better now. I understand the reasoning behind it, just didn't like the way I felt walking out. I didn't go into detail about the specific use or loosely use the term rockets, just explain it's for ejection charges for parachutes for a hobby i enjoy, and use less than half gram. If I would have walked in with a lip full of dip, camo hat, wranglers, boots and a hunting shirt it would have been no problem.

Ask the vender at your local club. They usually carry it. No questions asked!

That's amazing. When I bought mine, I was all prepared to tell them it was for a muzzle loader. I was even going to tell them that my dad gave me a muzzle loader as a present, and that I have never shot it and don't know much about it, but that he was going to teach me, etc., in case they started asking.

But all they said was that I had to sign a ledger, and I walked out with a pound, no questions asked.

Maybe it's because I asked for Goex instead of Gotex. :wink: (Just funnin' with ya!)

When I bought mine 2 yrs ago, they didn't ask.

Of course, the perfectly correct way is to get the Explosives Permit. That way, when they ask you why you are buying it, you can tell them the truth, and show them the E.P.

Has anyone here WITH an E.P. done just that and still get rejected?

McKailas Dad said:

I have not yet jumped into DD, but if I were to, I would seriously consider the new Jolly Logic Chute Release.

It seems by the time you buy the deployment computer, e matches, black powder, build an AV bay, backyard testing, etc, it seems the Chute Release would still be less expensive.

Does anyone concur?

Click to expand...

I've used cable cutters with great results. But now that I've got a JL Chute Release, my cable cutters will go unused... I'll never go back. Same concept, simpler setup, easily transferred. No e-matches required. No altimeter required.
Cable cutters work. They're easy. But if you're dropping $130 between the cutters, e-matches and altimeter anyway.... The Chute Release will work for all your rockets with no need to build an av bay.... Seems like a done deal to me.

Dumb question but, you can use the CR to L1, right? And if you were to do dual deploy use 2 of them, one on drouge at one end of shock cord and another at the other end to the main, set at different altitudes? Make sense? Would that satisfy L2?

I'd be wary of that. I'd hate to see a successful launch ruined because your two chutes fouled each other.

Rob702Martinez said:

Dumb question but, you can use the CR to L1, right? And if you were to do dual deploy use 2 of them, one on drouge at one end of shock cord and another at the other end to the main, set at different altitudes? Make sense? Would that satisfy L2?

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I'd guess it would depend on your 'attitude'. I've seen both schools, some get their L1 with a fat rocket, a baby H, and lob it to 1200' for the easy cert, and some have hammered them up with an I in a minimum diameter, stuffed full of electronics.

Your call, but I, personally, would likely take the easy route, get the Cert, -then- get into the gadgets and gizmos.

Rob702Martinez said:

Dumb question but, you can use the CR to L1, right? And if you were to do dual deploy use 2 of them, one on drouge at one end of shock cord and another at the other end to the main, set at different altitudes? Make sense? Would that satisfy L2?

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No electronics are required for Level 2. You need to have your chosen recovery method work, and you need to recover the rocket in reflyable condition. Prior to level three, you will need to have demonstrated electronic recovery success, and use redundant electronics for your L3 flight.

My L1 was a 54mm baby H to ~2500 feet, pop at the top and a short-ish walk. For CR with a drogue, I'd use motor eject at the top to push the drogue and (wrapped) main out, then have CR deploy the main at whatever altitude you like. I would probably try going without a drogue first since that's less chance of fouling and the wrapped main will have some air resistance. Caution: I've never actually done this, so YMMV and people who have done it with cable cutters may have better info.

Rob702Martinez said:

Dumb question but, you can use the CR to L1, right? And if you were to do dual deploy use 2 of them, one on drouge at one end of shock cord and another at the other end to the main, set at different altitudes? Make sense? Would that satisfy L2?

Click to expand...

The chute release is a lovely product but does not cause airframe separation. You could probably use them to bundle or restrict parachutes on either side, but you still need to get separation and get that bundle out. That most likely means you are using black powder to begin with, so you may as well simply release the parachute as normal at that point.

Where the chute release shines, is doing dual deployment out of a single separation, with motor ejection or separate altimeter providing the initial blast.

Keep in mind, also, that Chute Release is a single-function device that releases your chute. If you want any kind of data logging, altitude reporting, velocity reporting, etc., you'll need a second altimeter and an AV bay. So I don't see CR completely eliminating cable-cutters; but for simply releasing a chute at a set altitude, it really seems like the way to go.

BTW, I have a CC and a CR and plan to continue using both.

I'm going to have to try again at some point as my ejection charges are going to require more BP.

"My dad/brother/cousin has a muzzle-loader and there are no gun shops near him. I am buying this for him, and we are going to go out shooting this/next weekend. I don't know anything about it; he's going to teach me when I get there."

Memorize this. :wink:

Bat-mite said:

"My dad/brother/cousin has a muzzle-loader and there are no gun shops near him. I am buying this for him, and we are going to go out shooting this/next weekend. I don't know anything about it; he's going to teach me when I get there."

Memorize this. :wink:

Click to expand...

I used something similar. I was quick on my feet when the sales person asked if I had a muzzle loader, and if that's why I was buying BP.

That's when I said, "No, I don't, but my father in law does..some kinda Civil War reenactment thing I think, but I'm not sure. I'm just the driver"

It worked

My cable cutter experience is limited, was a success even though I didn't see it. I can't find the link here but I copied a fellow who sewed a loop in the apex of the chute canopy. (No spill hole). He then threaded a small ball through the loop to act as a "stopper". I used a piece of dense heavy foam instead of a ball. I put a 10" drogue on the end of the loop. I packed the main 36" chute and used the the heavy foam as a cinch point for the zip tie. The main was wrapped in nomex and gets shoved in first.
The drogue gets placed forward of the main package and I wrapped a little flame resistant tissue since the main chute package acts as an erstwhile protector.

At deployment, the package is expelled and the 10" drogue is deployed for initial slowing. When the cable cutter blows/severs the ziptie, the drogue keeps the chute aligned and aids with extraction from the nomex. Worked great on a minimum diameter
38mm J350 rocket that went to 8500 feet. Would'a gone higher if the rail guide didn't bind on the rail.

The download from the EggFinder TRS showed a typical DD pattern of descent. The break from the apogee descent to the main release was a pretty sharp change in line slope so it likely deployed quickly even though I couldn't see the event.
God bless the GPS tracker. Walked right up to it. Kurt