Zephyr Dual Deploy Conversion

[TheTank]

Started flying dual deploy a couple months ago after getting my L1 back in July and really enjoy it. I decided to modify my L1 Cert rocket, Zephyr, to dual deploy so I can stuff some larger motors in it and maybe not lose it here in the northeast.

I started planning out what I needed and I need to give a shout out to Tim at Apogee. When I emailed just to confirm I was picking the right tube size to match the OEM Zephyr tube, he pointed me in the direction of his dual deploy kit that i didnt know he offered. I checked it out and it was most of what I needed and cheaper than if I sourced the items separately (included a drogue, chute protector, etc). I ordered that up along with a 48” chute and called it a day. I ordered altimeters and switches from Missleworks. When the conversion kit came in, it appeared to be all quality materials.

 

[TheTank]

The kit included instructions but assembly was simple. Center the vent band and glue. Glue in the inner rings for the bulkheads to sit against, assemble the single bolt sled (a little sanding was needed to achieve my desired fit as it was tight at first). I opted to make this my first dual deploy with redundant electronics so after playing with the layout a bit and the single bolt design, i opted for a side by side layout out of necessity. I used two pvc caps as charge wells along with two fuse blocks and silicone insulated wire. Eyebolts and through bolts came with the kit. I also brushed down the face of the bulkhead with epoxy for easier cleanup down the road from the black powder.

 

[Buckeye]

Agreed, Apogee has everything for one-stop shopping. Very convenient.

Are the chutes the silky-smooth, lightweight ones? Those are SWEET - good quality, easily packed, and inexpensive. I am not a parachute snob, and I can't bring myself to purchase chutes for 100's of dollars when these do the job. Unfortunately, they are made in China, but Tim is upfront about it on his webpage.

 

[TheTank]

Electronics came in which were two missleworks altimeters (RRC2+) and two screw switch setups. I am also using two 2S, 300mah 30c lipo batteries for power per my preference and experience with lipos. Installation was simple and clean with ample space. Batteries are on adhesive foam + straps and altimeters are on Missleworks mounts. Switches in the center which are both accessible through the same vent band hole. I also used to MPX connectors that I had on hand so I can easily unplug one side for dissaembly. They fit perfectly in the pre-cut slots as an added bonus.

I configured the primary to fire at apogee and main at 500, backup for apogee +1 and main at 300. I also differentiated the sound of the beeps so I can be sure both were armed and ready when the time comes. I powered them up and tested continuity with no issues.

 

[TheTank]

Agreed, Apogee has everything for one-stop shopping. Very convenient.

Are the chutes the silky-smooth, lightweight ones? Those are SWEET - good quality, easily packed, and inexpensive. I am not a parachute snob, and I can't bring myself to purchase chutes for 100's of dollars when these do the job. Unfortunately, they are made in China, but Tim is upfront about it on his webpage.

Yes, the 18” drogue he includes is one of his. I purchased a 48” apogee chute as well (As it didnt come with a main) as I have had good experience with them as well and if torch a hole in it, i wont be too concerned. He isnt the cheapest on a lot of things but these chutes are a good deal in my opinion.

 

[TheTank]

In addition to the vent band holes, i added three removable rivets from the kit to lock the payload to the av bay and i opted for two 2-56 shear pins on the cone and a single shear pin on the booster into the av bay as I wanted to ensure I avoided a drag separation. Once that was complete with a little paint, the conversion was done and it was on to testing. Before.... and after... (ive since painted the vent band green to break up the white).

 

[TheTank]

Charge testing complete... A little hot on the charges I feel so Ill back the primary down slightly and leave backup as tested. Waiting on the next event to fly it. Hopefully the weekend after Halloween.

 

[Ganji]

Charge testing complete... A little hot on the charges I feel so Ill back the primary down slightly and leave backup as tested. Waiting on the next event to fly it. Hopefully the weekend after Halloween. View attachment 436556
View attachment 436557

How did you connect the nosecone to the airframe so it didn’t fall out while deploying first chute and it did fall during second chute deployment ?

 

[TheTank]

How did you connect the nosecone to the airframe so it didn’t fall out while deploying first chute and it did fall during second chute deployment ?

Im using two 2-56 shear pins to hold the cone secure during drogue ejection. The second ejection is strong enough to break/shear the pins and deploy the main when the time comes.

 

[markg]

I configured the primary to fire at apogee and main at 500, backup for apogee +1 and main at 300. I also differentiated the sound of the beeps so I can be sure both were armed and ready when the time comes. I powered them up and tested continuity with no issues.
View attachment 436552

Very nice looking AV Bay, great job! For flight-ready setup I'd suggest an extra vertical zip tie on each battery.

cheers - mark

 

[TheTank]

Very nice looking AV Bay, great job! For flight-ready setup I'd suggest an extra vertical zip tie on each battery.

cheers - mark

thanks! I plan on adding another zip tie. Ive gotten lucky so far with the adhesive foam tape with no issues on my other dual deploy rockets... but that luck is probably on borrowed time.

 

[markg]

thanks! I plan on adding another zip tie. Ive gotten lucky so far with the adhesive foam tape with no issues on my other dual deploy rockets... but that luck is probably on borrowed time.

Oh sorry, I didn't see that about the foam tape on my first read. Yeah, that's likely good enough for all but the most extreme cases. It's a nice looking rocket, good luck with your flights.

cheers - mark

 

[Dan Griffing]

In addition to the vent band holes, i added three removable rivets from the kit to lock the payload to the av bay and i opted for two 2-56 shear pins on the cone and a single shear pin on the booster into the av bay as I wanted to ensure I avoided a drag separation. Once that was complete with a little paint, the conversion was done and it was on to testing. Before.... and after... (ive since painted the vent band green to break up the white).

View attachment 436553
View attachment 436554
View attachment 436555

That’s how I upgraded my Zephyr for my L2.

Dual deployment isn’t necessary for an L2 but it helps demonstrate that you’re ready.

But there are many important points to charge and chute configuration and packing that are essential to a successful recovery. I recommend lots of ground testing.

 

[TheTank]

That’s how I upgraded my Zephyr for my L2.

Dual deployment isn’t necessary for an L2 but it helps demonstrate that you’re ready.

But there are many important points to charge and chute configuration and packing that are essential to a successful recovery. I recommend lots of ground testing.

I typically only test enough to ensure the charges are adequate. I use the same packing technique every time I load a chute in any rocket to ensure consistency. So far so good and have about a dozen back to back successful dual deployment flights since I started DD a couple months ago. Once my charges work with my packing technique, i try not to put the additional stress and wear and tear on the airframe, especially a cardboard one.

 

[Dan Griffing]

a dozen back to back successful dual deployment flights since I started DD a couple months ago.

You can’t argue with a whole dozen back to back successful dual deployment recoveries.

Not even a dozen ground tests would tell you more. You must be doing the right thing.

Every BP ejection charge firing puts stress, wear and tear on an airframe tube, especially a cardboard one.

That’s why I hope I can successfully implement the Peregrine CO2 ejection system I have in the DD rocket I’m now building, but with BP as a backup. But I’ve also wrapped the airframe sections with carbon fiber to make it more rugged and durable too.

 

[TheTank]

Dont think I ever followed up on this thread I started after the re-maiden. Flies great. Very happy with the conversion and a great addition to my fleet of dual deploy rockets. The redundant RRC2+ altimeters have been flawless so far. Has flown in the new DD configuration on an RMS 29mm/360 I200W and an H268R. Both flights went slightly under sim projects at 1350 and 1230ft. Now time to throw some larger motors in there.
View attachment trim.63053522-4488-4CC1-B2E0-FE1DD9855280.MOV

 

[TheTank]

 

[TheTank]

Another shot from the maiden the weekend prior at the METRA club. Photo by Andrew Cook.

 

[MikeT]

Just wondering if there was a CG change when you added the electronic bay to the Zepher. I'm doing the same conversion.

 

[waltr]

Just wondering if there was a CG change when you added the electronic bay to the Zepher. I'm doing the same conversion.

With all the DD rocket I have built, the DD bay with electronics and battery does move the CG forward. If you plan to fly bigger motors this is a good thing.

As course it does take long to do a sim in Open Rocket to see how much the CG changes with and without the bay.

 

[MikeT]

Thanks. I kinda figured that.

Mike

 

[TheTank]

Just wondering if there was a CG change when you added the electronic bay to the Zepher. I'm doing the same conversion.

It does, but I think the rocket flies much better extended and in DD configuration. Mine has 4 flights in original setup… 25+ in DD configuration through every J i can stuff in it.

 

[MikeT]

Thanks.
Mike

 

[Lord Rory Gin]

Just wondering if there was a CG change when you added the electronic bay to the Zepher. I'm doing the same conversion.

Both the CG and CP will change. Rocksim will show you by how much for the CP but you should find your own CG point as construction may vary a little from the sim.

 

[rocketman328]

Rocketry 101, kinda of a dumb question

 

[MikeT]

Rocketry 101, kinda of a dumb question

Thanks for your support. Been my experience to inquire with ones that have built and flown a system I'm building. As the old saying goes there are no stupid questions.......But there are stupid replies.

Mike

 

[loopy]

Thanks for your support. Been my experience to inquire with ones that have built and flown a system I'm building. As the old saying goes there are no stupid questions.......But there are stupid replies.

Mike

You are exactly right. I'd rather have people ask these questions than have them make assumptions about things they don't understand and end up crashing things. Ignore the negativity you'll find out here from time to time. As with any site, you'll have the occasional grump, but by and large, we like to help as much as possible.

 

[techrat]

I was just about to note that I thought I saw this rocket at the METRA meet on October 8th, when I was there.... I thought it had been modified because it looked taller than a standard Zephyr, at the time, I thought this was a kit-bash or something, but now I see it's the Dual Deploy version of this rocket. Never realized the plywood fins were so thick on this kit (as I'd only seen youtube videos). But now I see that I'm definitely ordering this when I do my L1. The Zephyr looks like a good solid rocket up close now that I've seen on in real life.

 

[MikeT]

You are exactly right. I'd rather have people ask these questions than have them make assumptions about things they don't understand and end up crashing things. Ignore the negativity you'll find out here from time to time. As with any site, you'll have the occasional grump, but by and large, we like to help as much as possible.

Your absolutely right.

Mike

 

[MikeT]

I was just about to note that I thought I saw this rocket at the METRA meet on October 8th, when I was there.... I thought it had been modified because it looked taller than a standard Zephyr, at the time, I thought this was a kit-bash or something, but now I see it's the Dual Deploy version of this rocket. Never realized the plywood fins were so thick on this kit (as I'd only seen youtube videos). But now I see that I'm definitely ordering this when I do my L1. The Zephyr looks like a good solid rocket up close now that I've seen on in real life.

It's a great L! rocket many of our section members got their L1 with it. I purchased one along with ebay conversion as I'm going to play around with dual deploy and wanted a 38mm to test my electronics. I could have used one of my 29mm rockets but I felt like building something new.

Mike