First DD kit

[AfterBurners]

Do you any of you have any recommendations for a good DD kit. Nothing crazy in size, maybe under 3" and also maybe some recommendations for electronics?

Also what is the smallest diameter that you would go with a DD?

Thanks a bunch!!

 

[teepot]

The smallest diameter is going to depend on the weight. Because of the weight you have to be able to get the right size chute into the tube. The smallest I build is 2.6". The last 2.6" I did was 43 ounces empty. With electronics and a spent motor it's 50 ounces and needs a 60" main which just fit. The electronics I use is Missile Works RRC3. 3 pyro channels and easy to program with the LCD accessory.

 

[WillMarchant]

Well, IMHO, 4” is about an ideal size. While people do DD in smaller diameters (down to 18mm) it gets more difficult to cram stuff in. For a first DD I suggest keeping things a bit simpler by going a bit larger.

We’re living in a golden age of electronics. Missileworks , perfectflite, altusmetrum, and others make great devices. I recommend reading the manuals before buying to make sure you understand what the vendor is saying. Like cars, the different vendors have different “feels” to their systems. You have to really know your electronics.

Prepare a checklist. Use it! Make sure it shows the expected lights or noises your avionics will make. Pay attention to those.

Use motor ejection as backup until you get familiar.

I like the Binder Design Excel series, myself.

Have fun with this!

 

[grouch]

I'm a fan of 54mm tubing for dual deploy although anything larger makes packing and sorting much easier. Anything smaller can be done for sure but it's considerably more tedious. The Missile Works RRC2 makes a fantastic first altimeter as well as a StratoLogger CF if you can find one. They are both fantastic. The RRC2 is supper simple and the dip switches makes it easy to adjust at the launch depending on the weather conditions. Can't say enough good things about them. The StratoLogger is a little more involved but has data logging if that's important.

As far as kits go, anything on the shelf can be made DD with the addition of an AvBay and an extra section of body tube. Pick what you like and start building.

 

[MikeyDSlagle]

My first DD was a 2.6" fiberglass scratch build, which was also my L1 rocket. It is a good size to learn on and easy to get everything in there without getting too heavy.

Smallest I would go is 54mm. Many rockets can turned into dual deploy, some are easier than others of course. For first time DD, 2.6" or 3" would be great.
Specifically:
Binder Excel dual deploy
LOC Deployer
Upgrade either to a 38mm motor if possible. Single grain 38s are fun and Loki two packs ship Hazmat free.

Don't dismiss PML. Their kits are great, a good step up from paper and wood. They will take more rough handling than paper. You will likely have to convert most of them to DD though. Not sure which ones come with DD.

The electronics...
I have flown Eggtimer, Missileworks, and Adept. Had good luck with all of them.
For simplicity, I don't think you can beat the RRC2+. It is fairly small, reliable and stupid simple. Set a few DIP switches, listen to the beeps and fly it. Beeps out altitude afterward. There is now a version, RRC2L, that uses the LCD screen. Adds a bit of complexity but nothing major. I had a rocket come in hot with a RRC2+and an Altimeter 3 on board. The Altimeter 3 was totaled, the RRC2+ still flies. The Missileworks store also has printed sleds, battery connectors and switches; so you can grab pretty much all you need right there.

9 volts will work, have for decades, but I prefer 2 cell LiPos. I still use 9volt in a few rockets.

 

[OverTheTop]

Check out Binder Design and see if there is something there you like.
http://binderdesign.com/
Lots of good choices for altimeters. I have more Ravens than anything else. Great all-round alt IMHO.

As Will mentioned earlier, implement a checklist. It will save your bacon.

 

[Jmhepworth]

For me, a three or four inch diameter rocket is the sweet spot for dual deploy. The av bay is big enough that it’s not a puzzle to make everything fit. If I can make two altimeters fit, I use two. It’s not too bad getting two into a 3 inch diameter av bay. 54mm is doable but more of a challenge. I haven’t tried to get two into a 38mm bay, but one fits nicely. One of my favorites was to put an altimeter into a 29mm Apogee Aspire. Tim’s av bay kit for the Aspire makes it easy. At the other extreme, I launched an Ultimate Wildman yesterday. A 6 inch av bay is cavernous.

 

[Jmhepworth]

For a first altimeter, you can’t go wrong with an RRC2+. It’s simple to use. And if you like to solder, the Eggtimer products are great. But I think I would start with the least complex—an RRC2+. Learn from that and then buy more complexity as you have the need. For example, I have a Raven, a Marsa, and a Telemetrum. But I use those for staging and tracking. Start simple.

 

[David Schwantz]

https://www.madcowrocketry.com/1-6-fiberglass-mini-dx3-dual-deploy/
This has made a GREAT DD kit. Cheap to fly on 29mm and easy to transport.

 

[AfterBurners]

thanks guys this should be interesting. Like I said first time around. Do I need any redundancy? I'll probably go with either a Binder or Madcow design. I've always liked the Patriot and they are about the same price.

 

[bobbyg23]

Loc deployer! Comes with everything you need. Get it from flightsketch.com for free shipping and a great price. Excellent and affordable. Loc kits are awesome. You don't need redundancy.
https://locprecision.com/product/deployer/

 

[bobbyg23]

thanks guys this should be interesting. Like I said first time around. Do I need any redundancy? I'll probably go with a Binder design. His kits seem to come with everything you need.

https://flightsketch.com/store/catalog/loc-30-deployer_243/

 

[Jmhepworth]

thanks guys this should be interesting. Like I said first time around. Do I need any redundancy? I'll probably go with either a Binder or Madcow design. I've always liked the Patriot and they are about the same price.

It’s all too easy to make mistakes when starting with dual deploy. I’ve made so many mistakes I could write a book. Using motor ejection as a backup is wise, as well as a larger than necessary drogue chute, until you build confidence. I like redundancy when I can make it fit. Create (and use) a checklist. I have one for rocket assembly and another that I take to the pad. And let a more experienced flyer look over your setup. Trying something new isn’t the time to think you know what you don’t know. Don’t forget to have fun as you learn. The complexity is both fun and educational.

 

[mtnmanak]

A great kit on the market is the Apogee Level 2 kit - comes with everything except the electronics.

All the Patriots are cool and are easy to build.

The Wildman 3 Dual Deploy is dirt simple to make.

All the Wildman Darkstar rockets are awesome - the 4" Dual Deploy is a great rocket to start with, gives you the versatility of flying anything from an H to an L on it. Only issue is the dual fin setup - that may not be the easiest thing if you aren't used to it.

The Madcow 4" Fiberglass Super DX3 is a classic and another easy build.

Lots of great Black Brant II's out there - Composite Warehouse has a nice 4" kit in stock.

Would second the Missileworks series of electronics. Depends on the size of your rocket. If you go 3" or smaller, the RRC2 series is great - compact and easy to use. Although, I would recommend the newer RRC2L over the RRC2+. The ability to use the MW LCD controller makes the RRC2L much easier to use. You can program it at the field with no problem. If you end up going with an airframe 4" or larger, just spend the extra few bucks on an RRC3. The addition of a dedicated switch port makes it easier to wire up for your first try, rather than trying to figure out how to wire the switch in series to your battery port (as you will have to do on an RRC2). The other nice thing about MW is you can just buy one of their 3D printed sleds and make your life a whole lot easier for your first DD build.

Probably the only thing easier to use for electronics are the Perfecflite Stratologger CFs, but they are notoriously difficult to get ahold of.

As far as how small you can go, I have a fully dual deploy fiberglass minimum diameter 29mm rocket with an RRC2L in it. It flies nicely to about 1500 feet on an F52 and to about 9000 feet at 800 MPH on an I200. It uses a slick little 29mm sled from MW:

 

[thzero]

Why not something like Bt70 based rocket? It's bigger slightly than 54mm tube, but certainly lighter weight.

Means you can learn on smaller motors.

 

[gtg738w]

The LOC Deployer is a great start but as mentioned pretty much anything can be made dual deploy. To start with you can build the kit and just fly motor eject. Then add complexity as you feel more comfortable. That takes some pressure off and almost guarantees a safe recovery even if you miss something in the electronics.

To go smaller, just remember you may not need all of the traditional DD gear. A single altimeter w/motor backup, no drogue and streamer main will fit in very small sizes. You don't have to take a full 4" setup and try to cram it in a smaller tube...

 

[Bat-mite]

Do I need any redundancy?

You don't need it; but if you get a failed ejection and a core sample you might look back and wish you had it.

For a small rocket, I'd go with an AltusMetrum easyMini. Full DD recording altimeter with a standard USB interface, very small form factor, wide variety of acceptable batteries.

 

[DragonRocketry]

This is a good kit to do dual deployment on. I flew it yesterday to 1800' on a G64.

 

[John Kemker]

My first DD was a stock EZI-65 that I retrofitted an altimeter inside the payload bay and put the mains in there. The apogee charge simply separated the payload bay from the main airframe, then the mains charge popped the nosecone off at 500 ft. AGL, deploying the chute. Short walk and all was good.