Dual Deploy Kit Suggestions

[dr wogz]

Oh yes!! Binder design kits rock!

 

[Jee3300R]

Also, ARR has some 4" blue tube kits with 54mm mounts at a good price. They go together nicely with some wood glue and build much like cardboard rockets. Blue tube is stronger than cardboard. A 4" blue tube rocket will survive any 54mm motor and should still be light enough to go on some H's.

 

[heada]

Estes StarOrbiter (less than $20) with Apogee BT-60 av-bay (less than $20) and either a Quark or EasyMini or SLCF (if you can get one) (between $20 and $100)

29mm but still still fly fine on 24mm so low cost per flight *and* can fly as Class 1 (non-HPR)
Low over-all investment
If you can DD in 1.6" then 4" will seem so easy it's crazy

 

[caveduck]

My altimeter is going to be an EggTimer Quantum. I built an EggFinder tracker for my L2 flight and it worked perfectly. I picked up the Quantum during the holiday sale along with some of Cris’s new apogee deployment flight controllers to practice on a smaller scale.

Good stuff. I really like the Quantum, great combo of size, price, capability and WiFi remote goodness. Switching on both the hot and ground sides is a great safety feature. It's my go-to flight computer now.

 

[Scott_650]

Estes StarOrbiter (less than $20) with Apogee BT-60 av-bay (less than $20) and either a Quark or EasyMini or SLCF (if you can get one) (between $20 and $100)

29mm but still still fly fine on 24mm so low cost per flight *and* can fly as Class 1 (non-HPR)
Low over-all investment
If you can DD in 1.6" then 4" will seem so easy it's crazy

That’s my plan for the tubing and nose cone from my old Custom Rockets Equinox - it’s beat up from multiple hard landings so it’s heading for a total refit as a much shorter EDEX - electronic deploy experimental - with an Eggtimer Apogee and an Easymount. Can’t get much more low buck than parts from a rocket I already have and Eggtimer stuff bought during the Black Friday/Cyber Monday sale.

 

[SecondRow]

That’s my plan for the tubing and nose cone from my old Custom Rockets Equinox - it’s beat up from multiple hard landings so it’s heading for a total refit as a much shorter EDEX - electronic deploy experimental - with an Eggtimer Apogee and an Easymount. Can’t get much more low buck than parts from a rocket I already have and Eggtimer stuff bought during the Black Friday/Cyber Monday sale.

I’ve got an Estes Prowler that I’m thinking about retrofitting with my Apogee and Easymount to practice electronic deployment.

 

[Scott_650]

I’ve got an Estes Prowler that I’m thinking about retrofitting with my Apogee and Easymount to practice electronic deployment.

Those Estes E2X PSII rockets are great for modding - should work well with an Apogee. Post your progress...

 

[DAllen]

If you want to make nicer looking fillets than what plain wood glue can deliver get some Titebond Mold and Trim a.k.a. Quick and Thick.

 

[SecondRow]

If you want to make nicer looking fillets than what plain wood glue can deliver get some Titebond Mold and Trim a.k.a. Quick and Thick.

Done!

 

[Ronz Rocketz]

It’s inevitable. Don’t you know?

For any thread x, \[ \lim\limits_{t \to \infty} \ Topic_t(x)= Glue \]

What is the derivative of Glue?

 

[Donnager]

What is the derivative of Glue?

Sanding dust and hand boogers.

 

[SecondRow]

Those Estes E2X PSII rockets are great for modding - should work well with an Apogee. Post your progress...

Seems like the Prowler may not work. I need a one inch hole for the Apogee, but that will interfere with the shock cord mount. See here.

I can cut all that off and insert a bulkhead, but the chamfer is so steep that after I cut it off, I’ll be left with only a 5/8” shoulder for the NC. Is that long enough? The original shoulder is 2 inches long.

After giving it a little more thought, I could probably epoxy a coupler in there to extend the shoulder, couldn’t I?

 

[Scott_650]

Seems like the Prowler may not work. I need a one inch hole for the Apogee, but that will interfere with the shock cord mount. See here.

I can cut all that off and insert a bulkhead, but the chamfer is so steep that after I cut it off, I’ll be left with only a 5/8” shoulder for the NC. Is that long enough? The original shoulder is 2 inches long.

After giving it a little more thought, I could probably epoxy a coupler in there to extend the shoulder, couldn’t I?

That’s an option. Though you might be able to install the Easymount off center, lop off the molded eyelet and drill two holes in the angled shoulder to loop the shock cord through - it might all fit then. Try it that way and if it d fit you can still use a coupler and bulkhead...

 

[_kestrel_]

I’m thinking about a 4” 54mm rocket. Big enough to fly H and I motors to low altitudes for DD practice, but still able to fly J and K when I feel ready. Also, big enough to lay out the electronics easily. I’m looking for cardboard tubes and wood fins - I don’t have the setup to do a lot of epoxy construction. I don’t feel like working with FG, phenolic, etc.

I understand your decision to avoid fiberglass. I had a lot of the same concerns but went ahead and bought a Mach 1 Warhead when it was on sale last year. I've found fiberglass to be easier to work with than expected. I have (an unfinished) build thread going on for the Warhead, modified to head-end dual deploy. All I have left to do is add shear pins, vent holes, and paint. I'll finish it up when it isn't below zero.

I also picked up a Madcow Python ( https://www.madcowrocketry.com/54mm-fiberglass-python/ ) when they were on sale over Black Friday. I'll be building that with an Eggtimer Apogee. The key thing there was the low cost of launching and refining electronic deployment techniques. The Python sims to around 1000 feet with the Aerotech F67 motors. That will keep the rocket in sight for the full flight and will only set me back about $12/launch. I'm lucky to have an Aerotech dealer that comes to our launches and have ready access to these lower cost motors. I can get 3 or 4 flights of the Python to one flight on the Warhead with a 38mm DMS motor. This is similar to what you proposed above with the Prowler.

Sticking with cardboard and plywood, how married are you to the idea of the 54mm motor mount? The Loc Athena ( https://locprecision.com/product/athena3/ ) is a 3" rocket that could be easily modified to dual deploy. The 29mm motor mount could be a plus or minus, cheap to fly but limiting when it comes to letting 'er rip if the waiver and conditions allow.

The Athena's big brother might fit the bill too. The Mystic Buzz ( https://locprecision.com/product/ybuzz4/ ) is a 4" cardboard and ply rocket with a 54mm mount that would be an easy conversion to dual deploy.

There are a ton of options out there and I am following this closely as I am in a similar place to you, just getting going with electronics and wanting to learn. Thanks for starting this thread - I'm getting lots of ideas for future rockets to build.

 

[Dan Griffing]

Apogee Katana is a good choice. Comes with EVERYTHING, sans motor retention. Includes all the fundamental parts for an electronics bay. Excellent instructions.

The Apogee Katana is an excellent choice and is probably the best buy for a complete solution.

The only downside is that its a cardboard airframe rocket. But fiberglass alternatives cost much more and are more difficult to build.

 

[Dan Griffing]

Good stuff. I really like the Quantum, great combo of size, price, capability and WiFi remote goodness. Switching on both the hot and ground sides is a great safety feature. It's my go-to flight computer now.

I love Eggtimer DD controllers and GPS trackers. I especially like the 6-channel Proton because it allows you to have primary and backup drogue chute deployment channels, as well as primary and backup main chute deployment channels, each set to different parameters.

The ejection charge power can be switch-isolated from the electronic power, and the remote WiFi arming, and remote ejection charge testing and essential features.

 

[thzero]

The Apogee Katana is an excellent choice and is probably the best buy for a complete solution.

The only downside is that its a cardboard airframe rocket. But fiberglass alternatives cost much more and are more difficult to build.

More difficult? Not really. Some additional precautions certainly, especially if not using epoxy with the carboard kits, but otherwise its same process.

 

[SecondRow]

That’s an option. Though you might be able to install the Easymount off center, lop off the molded eyelet and drill two holes in the angled shoulder to loop the shock cord through - it might all fit then. Try it that way and if it d fit you can still use a coupler and bulkhead...

The amount of space available was less than the 1” I needed for the Easymount. It wouldn’t fit, even off-center. I ordered a coupler and bulkhead from Erockets. When the parts get here, I’ll start a separate thread and we can see how it goes.

 

[SecondRow]

I understand your decision to avoid fiberglass. I had a lot of the same concerns but went ahead and bought a Mach 1 Warhead when it was on sale last year. I've found fiberglass to be easier to work with than expected.

It’s really because of my workspace. It’s not cut out for a lot of epoxy use and FG. Wood glue is easier to clean up than epoxy when I accidentally get it on the desk or carpet.

Sticking with cardboard and plywood, how married are you to the idea of the 54mm motor mount?

I’m all in on 54mm for this one.

The Athena's big brother might fit the bill too. The Mystic Buzz ( https://locprecision.com/product/ybuzz4/ ) is a 4" cardboard and ply rocket with a 54mm mount that would be an easy conversion to dual deploy.

I like this one, too. But it looks like LOC is out of stock on their 4” electronic bays.

 

[Bowman]

I had a 3" Mystic Buzz years ago. Nice flying rocket and nicely kitted.
I believe it was manufactured by Yank IIRC.

 

[Scott_650]

It’s really because of my workspace. It’s not cut out for a lot of epoxy use and FG. Wood glue is easier to clean up than epoxy when I accidentally get it on the desk or carpet.


I’m all in on 54mm for this one.

I like this one, too. But it looks like LOC is out of stock on their 4” electronic bays.

Other vendors have those 4” e-bays in stock - Buyrocketmoters shows it on their website.

There is much to be said about building with non-toxic, water based stuff if you’re working in a shared space. My fiberglass kits are waiting for warmer weather when the garage shop is habitable - it’s a balmy 20F out there right now.

 

[Scott_650]

I had a 3" Mystic Buzz years ago. Nice flying rocket and nicely kitted.
I believe it was manufactured by Yank IIRC.

LOC and Yank are together - the current owners of LOC were the guys behind Yank, Dave Barber and Jason Turicik. They were the ones who moved LOC to Wisconsin. I remember being annoyed that I missed the sale they had here in NE Ohio before the move because I was busy at work - if only they’d have waited until I retired I did score some discounted 1” kits via mail order.

 

[Pete.D]

The Apogee Katana is an excellent choice and is probably the best buy for a complete solution.

The only downside is that its a cardboard airframe rocket. But fiberglass alternatives cost much more and are more difficult to build.

Definitely Katana. I built mine using wood glue and got my L2 on an J335 with 2 lbs ballast. The motor ejection was 4 seconds late (possibly my fault since I set the delay); it partially shredded the chute and landed hard on its side with NO DAMAGE. Tough rocket, especially considering the ballast needed to avoid blowing through the 3000 ft waiver.

 

[Scott_650]

Definitely Katana. I built mine using wood glue and got my L2 on an I335 with 2 lbs ballast. The motor ejection was 4 seconds late (possibly my fault since I set the delay); it partially shredded the chute and landed hard on its side with NO DAMAGE. Tough rocket, especially considering the ballast needed to avoid blowing through the 3000 ft waiver.

Not to derail this into the deep, muddy ditch of a glue discussion but any quality PVA glue will yield a bond stronger than the wood or paper being joined. Epoxy definitely has some advantages - for me the biggest two is that it doesn’t “seize” like PVA glues can when joining tubes and inserting motor mounts and it doesn’t shrink so as to cause dimples around centering rings. The downside is the toxicity and oder. Don’t discount the toxicity of epoxy, I know of more than one person who developed rather severe allergies to epoxies and fuels after working with them for years - nitrile gloves are a must!

The Katana would be a good choice, I don’t really care for the fin design but that’s a style thing - nothing to do with it’s functionality. My L1 rocket is built and thoroughly test flown just waiting on decent weather for the next club launch. It could work as my L2 rocket as well but I’m about to pull the trigger on a little bit different choice - an OOP U.S. Rockets Stiletto built for full dual deploy. Unless I chicken out and just fly my Crayon rocket with a baby J and call it done

 

[Dan Griffing]

The motor ejection was 4 seconds late (possibly my fault since I set the delay)

First, congrats on your L2. You got lucky by having no damage to your Katana after suffering from a partially shredded parachute.

I’m not criticizing you, but it would have been possible to use a dual deployment flight computer to fire ejection charges at the apogee and still have used single deployment and used motor ejection as a backup.

I got my own L2 cert with an Apogee Zephyr on a J270W, modified for dual deployment with the Apogee DD kit. Mechanically, except for the fin design and 54mm motor mount, this was a very similar rocket to your Katana.

In addition to having motor ejection as a backup, I used the Eggtimer Proton flight computer for redundant drogue deployment at apogee, and with redundant main chute deployment.

The Proton also has an option for firing the main chute charges if it detects a failure of the drogue deployment after the apogee is detected. So for parachute deployment to fail entirely, the motor ejection must fail, AND four instances of ejection charge firing by the flight computer has to fail as well.

Instead of regarding dual deployment as adding risk to successful chute deployment, I regarded it as an added insurance policy because I was wary about relying on motor ejection.

Ironically, at the launch a month later, I was relying on motor ejection only for testing single deployment with JLCR. On the third launch of the day, the ejection charge failed to blow off the nosecone and deploy the parachute, and the Zephyr came in ballistic from 2,000 feet, and was destroyed.

 

[Pete.D]

First, congrats on your L2. You got lucky by having no damage to your Katana after suffering from a partially shredded parachute.

I’m not criticizing you, but it would have been possible to use a dual deployment flight computer to fire ejection charges at the apogee and still have used single deployment and used motor ejection as a backup.

I got my own L2 cert with an Apogee Zephyr on a J270W, modified for dual deployment with the Apogee DD kit. Mechanically, except for the fin design and 54mm motor mount, this was a very similar rocket to your Katana.

In addition to having motor ejection as a backup, I used the Eggtimer Proton flight computer for redundant drogue deployment at apogee, and with redundant main chute deployment.

The Proton also has an option for firing the main chute charges if it detects a failure of the drogue deployment after the apogee is detected. So for parachute deployment to fail entirely, the motor ejection must fail, AND four instances of ejection charge firing by the flight computer has to fail as well.

Instead of regarding dual deployment as adding risk to successful chute deployment, I regarded it as an added insurance policy because I was wary about relying on motor ejection.

Ironically, at the launch a month later, I was relying on motor ejection only for testing single deployment with JLCR. On the third launch of the day, the ejection charge failed to blow off the nosecone and deploy the parachute, and the Zephyr came in ballistic from 2,000 feet, and was destroyed.

Thanks Dan, your comments are well founded. Indeed I was lucky; I believe the problem in my case revolved upon the use of ballast: besides lowering the apogee as intended, it screwed up my delay calculation (which I had determined using RockSim) and placed a more severe load on the parachute when it did come out.

I'm familiar with the Zephyr; it's very popular around here for L1 certification flights, and a nice rocket too: with its thick plywood fins it's as tough as the Katana, but a straight-in ballistic touchdown would destroy anything over a few ounces. I had used a MadCow Torrent for my L1 due to its potential for future DD; it was quite inexpensive from Apogee back then, but the price is MUCH higher now for some reason. It's too light for L2 cert around here anyway; ballast to remain comfortably under 3000 ft on a J would have doubled its weight.

I had been advised to "keep it simple" and avoid the use of electronics for my cert flights, especially since I had no experience with DD techniques. Using DD in a redundant mode is smart, and is apparently required for L3 certification flights. I'll be progressing to DD in the Spring; I've completed and tested an Eggtimer Quark, and a Proton is on the build pile along with their tracking system. Eggtimers are very cost effective as long as you're handy with a soldering station; I've soldered all my life and have some experience with surface-mount components.

 

[Dan Griffing]

Thanks Dan, your comments are well founded. Indeed I was lucky; I believe the problem in my case revolved upon the use of ballast: besides lowering the apogee as intended, it screwed up my delay calculation (which I had determined using RockSim) and placed a more severe load on the parachute when it did come out.

I'm familiar with the Zephyr; it's very popular around here for L1 certification flights, and a nice rocket too: with its thick plywood fins it's as tough as the Katana, but a straight-in ballistic touchdown would destroy anything over a few ounces. I had used a MadCow Torrent for my L1 due to its potential for future DD; it was quite inexpensive from Apogee back then, but the price is MUCH higher now for some reason. It's too light for L2 cert around here anyway; ballast to remain comfortably under 3000 ft on a J would have doubled its weight.

I had been advised to "keep it simple" and avoid the use of electronics for my cert flights, especially since I had no experience with DD techniques. Using DD in a redundant mode is smart, and is apparently required for L3 certification flights. I'll be progressing to DD in the Spring; I've completed and tested an Eggtimer Quark, and a Proton is on the build pile along with their tracking system. Eggtimers are very cost effective as long as you're handy with a soldering station; I've soldered all my life and have some experience with surface-mount components.

According to the onboard Altimeter3, my Zephyr DD L2 apogee was 3,032 feet without additional ballast.

The recovery system consisted of a Dino Chutes 18” X-Form drogue, a heavy, 48” Fruity Chutes Iris Ultra main chute, doubled Nomex oversized flame protection, the stock 1/2” 25 foot shock cord, and two additional sewn looped 25-foot Kevlar harnesses, and multiple heavy duty swivels and D-ring Quick Releases. The electronics bay contained an Eggfinder Proton flight computer, and GPS Tx, and a 1000mAh LiPo battery.

After fully configuring the rocket, I was surprised how heavy the rocket was. The launch weight was 8.24lbs.

The Montana launch sight was at an altitude of approximately 6 thousand feet, so this rocket’s apogee would have been under the 3,000 foot launch ceiling at lower altitude sites.

 

[Pete.D]

According to the onboard Altimeter3, my Zephyr DD L2 apogee was 3,032 feet without additional ballast.

The recovery system consisted of a Dino Chutes 18” X-Form drogue, a heavy, 48” Fruity Chutes Iris Ultra main chute, doubled Nomex oversized flame protection, the stock 1/2” 25 foot shock cord, and two additional sewn looped 25-foot Kevlar harnesses, and multiple heavy duty swivels and D-ring Quick Releases. The electronics bay contained an Eggfinder Proton flight computer, and GPS Tx, and a 1000mAh LiPo battery.

After fully configuring the rocket, I was surprised how heavy the rocket was. The launch weight was 8.24lbs.

The Montana launch sight was at an altitude of approximately 6 thousand feet, so this rocket’s apogee would have been under the 3,000 foot launch ceiling at lower altitude sites.

Well at 132 oz you actually WERE carrying quite a bit of ballast, in the form of your added electronics bay, electronics, forward body tube, heavy duty parachutes and associated hardware: the "book" weight of a Zephyr is 42 oz with its stock recovery system, and the motor you used added 23 oz more.

So your actual launch weight was over double that of a "stock" Zephyr, and was nearly as much as my Katana (which launched at 139 oz, or 8.69 lbs including 2 lbs ballast). I don't know how high the Katana went since it was carrying no electronics and only a single light-weight stock parachute, but apogee was estimated at 2500 ft AGL and the intended 10 second motor delay stretched out seemingly forever (hard to say for sure without instrumentation, but it was around 4 seconds past apogee). Amazing how the weight adds up; my unloaded Torrent weighs only 60 oz, and that includes an (empty) electronics bay and forward body tube.

I'd say you got good performance out of your custom recovery system; I'll consider that in future launches of my heavier rockets. I've noticed that many of the high-end kits don't even include a recovery system, likely because of the wide range of options available.

 

[Dan Griffing]

at 132 oz you actually WERE carrying quite a bit of ballast, in the form of your added electronics bay, electronics, forward body tube, heavy duty parachutes and associated hardware

It wasn’t exactly ballast, although it was almost everything but the kitchen sink.

My primary motivation wasn’t to add additional weight to limit the altitude, or to provide a 5x redundancy over simple motor ejection.

Instead it was because I was pushing my L2 certification just a month after my L1, and as a retired engineer new to HPR, I wanted to go well beyond the minimum L2 requirements by demonstrating my mastery of complex, advanced recovery techniques that are really required for L3 certifications.

It just so happened that this also made the rocket much heavier and increased its deployment reliability by adding a rugged and redundant recovery system.

You’ll probably discover for yourself that doing the same ruggedization and recovery reliability to your Mad Cow Torrent, or any other similar rocket, will add a similar amount of weight.

 

[Pete.D]

I was pushing my L2 certification just a month after my L1, and as a retired engineer new to HPR, I wanted to go well beyond the minimum L2 requirements by demonstrating my mastery of complex, advanced recovery techniques that are really required for L3 certifications.

Amazing, we're almost in the same boat: I"m also a retired engineer new to HPR, and my L2 flight this past November was similarly a month after my L1 cert! I'm planning next to subsequently develop my DD and redundancy skills, but probably not specifically for L3 since that would require a REALLY large and heavy rocket to avoid busting the local waiver on an M motor. You never know though; there's a NAR/Tripoli prefecture 3 hours away that regularly hosts LDRS events with waivers over 15,000 ft: I've never been there but it's on my list for a visit next summer, COVID permitting.