L3 - really?? Tekcub 3L

I started in rocketry in the early 1960's.
Exciting times with the space race - Mercury - Gemini - Apollo - Moon Landing - WOW
Then I faded out - went to college - got a job - married - kids
And the kids ended up with opportunities to do rockets - Hey - I did those when I was young!
So in 1998 I got back into it. Built several kits with the kids. They lost interest, but I continued on.

In 1999 I discovered the ESTES NCR kits, and F&G motors - OMG!

Joined NEPRA and at the 2003 NSL I got my level 1. Cool.

Mostly built LPR and some MPR. Happy with the L1.

Looked at L2, but always said "Nah - too expensive. I'll stay with my LPR"

BUT.... Rocketry Warehouse had other ideas. They offered their new X-Celerator with an introductory 1/2 off price...
Next stop L2. 2011

All right. Enough's enough. Got my L2 on a J. That's it. Wait DMS K motors? I'll try one.... Cool.
Hmm - Black Friday sale on a DMS L motor. 8360' - All time high altitude for me

Enough's enough though. This is getting expensive.

Fast forward to 2017. LDRS 36. Furthest I ever traveled for a launch . And Tim offers a deal on an Ultimate, casing, and motor. Ahh - it's only money!


L3 here I come! Been thinking and planning the design for a bit. Time to get moving

The obligatory parts pix for the Ultimate Darkstar.



And some of the parts I need to supply. Teddy's One Bad Hawk Kevlar harnesses, B2 Rocketry 15' chute, Wildman Recon Recovery drogue chute, Stickershock decal, Basswood, Plywood, Loc tubes and nosecones (say what?), Aeropack retainers, and other parts



You will notice in the above picture the plywood rings. Those are the first rings I've ever made using a fly cutter. I know, simple stuff for many of you but a first for me...

Back to those nose cones, tubes, and basswood. Where do they fit in.
Well, a while ago I got bored with 3FNC builds. Basically they are all the same.

At least the Darkstar has split fins, just like my L2 X-Celerator. But I want something different, so.....

I present ... The Tekcub 3L

View attachment 340281 View attachment 340282


(sorry for the double pix - re-added and original came back)

The basswood will be for the strakes
The LOC nose cones and tubes will be split and added as pods by the fins

Wow this should be cool! Will be watching. L3 is expensive but you don’t have to fly it all the time. Hope you have room for it!

I will say that anyone the walks into my garage, sees and , well they are conversation starters that’s for sure.

Looks like a very unique design and the Ultimate Darkstar will take any motor you can put in it (well I don’t know about the N10,000 - guess that could be build dependent) but 98-6XL will push it if you ever want to. Always been impressed with your builds so this design will be a crowd pleaser

Where do you plan to fly it? Might have to take a road trip for this



Sent from my iPhone using Rocketry Forum

The Ultimate Darkstar was my L3 rocket. Great fun to build and to fly. I used a Loki M900 and it was a great show. It's a little on the edge of being not quite enough push off the pad, but an 8ft rail and calm wind made for a nice straight flight. I went a little nuts with Stickershock and did a full wrap.

https://www.rocketryforum.com/showthread.php?140216-L3-build-Wildman-Ultimate-Darkstar

Nick@JET said:

Where do you plan to fly it? Might have to take a road trip for this

Click to expand...

URRF 5

For those interested, my Rocksim file. It will be tweaked as I work the build.

With the M2500 motor the sim shows just shy of 10,000'

View attachment tekcub_3L.rkt

les said:

For those interested, my Rocksim file. It will be tweaked as I work the build.

With the M2500 motor the sim shows just shy of 10,000'

View attachment 340354

Click to expand...

I like the name “Tekcub”. Sounds like it should be on a Tsil.

If I start flying 98mm then my rocket might have to be named Ecrovid.

Did some work on the motor mount. I messed up the drilling one ring (used a paper template instead of cardstock and the paper shifted)
This is attempt 2. Inserts mounted into the plywood ring. Added some dados for fin clearance.

Been doing some planning

Attached picture shows planned Drogue connection. Thanks to Teddy for the suggestions and for the harness. Great work from him, as usual.



And for my electronics, I will be using the Raven 2 and RRC2 mini that I used for my L2.
The Raven will use its magnetic switch on the Power Perch with a Lipo battery
The RRC2 mini will use a Missile Works screw switch and a 9V battery

I take advantage of the Raven's 4 channels by doubling up the e-matches for the backup

I dry fitted the mount pieces together - unless anyone believes blue masking tape can handle an M motor :lol::lol::lol:

The partial plywood rings were wood glued to the other ring. Those are my targets for the screws for the 1515 rail buttons
The foam ring is to help contain the epoxy when the fins are glued on.

I wanted a ring at the top so the harness would not rub against the edge of the motor tube (since replacing it will be virtually impossible.



No pix were taken, but I glued two 1/4" basswood sheets together. After drying I started cutting the strakes

Didn't make as much progress this weekend as I hoped.

But not to split hairs, I did split some tubes and nose cones.



And right now I don't have a need, but I decided to modify the nosecone bulkhead to allow access to shove something into the cone.
Cut out a ring and plug. Gluing the ring to the bulkhead.

Now, two questions....

1) - For the metal tip on the nosecone, do people normally allow it to be removable or make it permanent? My concern with being removable is if you try to remove it and the internal hardware may drop. Yes, I now have an access, but getting it all back together would be a pain. I'm tempted to go permanent but are there any reasons NOT to?

2) - A bit more unusual question/thought. I was trying to decide between using a deployment bag or not, and if I did whether to use an integrated configuration (nosecone and body remain attached) or independent configuration (nosecone come down on its own separate chute). Based on a few recent threads, there is no "right" way. Some feel the deployment bag is good, others feel it adds a failure mode. And if used, some want to keep it all together and others feel 2 separate pieces minimizes entanglement issues. And someone suggested I should not try something new, like the deployment bag, for a cert flight. So I had an unusual thought...... Skip the deployment bag. But still connect a pilot chute to the top of the main chute. Figure a 3' chute with a 25' cord. It can help pull the main out if needed. With the long cord, it should be up high enough that the main won't totally block the airflow. So, crazy or what? Anyone ever do this?

Its looking great. How do you physically break the connection between your Raven 2 and your pyro's?

And I would use a deployment bag. But don't like the idea of finding two halts of the rocket with the free bag style.

With a lower flight, finding two pieces (nosecone and everything else) is no big deal. At 10k ft, I think it might be a bad idea. You don't want to fail your cert because you couldn't find the nosecone. Granted, they won't separate until the main (low altitude) charge.

I did my nosecone on a separate chute for my L-3, only because it weighed 15 lbs. My flight stayed under 5k ft. You are going much higher, limiting visual tracking, and you won't be using large amounts of nose weight, eliminating concerns about bringing things down together. I see no reason to have your nosecone on its own chute.

Hi Les,
Good idea to document your L3 build as we can use this towards the Documentation for your package. I would also like a link to your Roc Sim file but I can wait until your finished and you have the final weights plugged into it so we can be as accurate on your sims as possible. Don't forget to add at least one photo of you working on the rocket and try to get photos of the areas that I won't be able to view once the build is complete, like of the internal fillets and such. I like what I see so far and will follow this thread.

Now as for your question on weather to free bag or not. On all of my large rockets I free bag and that is just my preference, you should do what is most comfortable for you, but when I do free bag I use two trackers, one in the nose cone and one in the rocket body so I can find both parts. Also I have found that even when both parts open and the main comes out, even at 5000' plus, that they tend to follow each other and land within a few hundred feet of each other.

By the way, here is my L3 Cert done at NSL 03 in Clark Summit, PA, and it was my first free bag flight. https://www.facebook.com/mike.dutch.9/videos/10204689203485427/?l=4609594767423528426&__mref=message

By the way, not to influence you or anything, this was also my second attempt. I failed my first attempt when the main would not come out. Which is why I free bag my large rockets now-a-days.

But again, you should do what is most comfortable for you, you decide which route you want to take.

Mdutch said:

By the way, here is my L3 Cert done at NSL 03 in Clark Summit, PA, and it was my first free bag flight. https://www.facebook.com/mike.dutch.9/videos/10204689203485427/?l=4609594767423528426&__mref=message

Click to expand...

The link does not work...

But nice coincidence that I got my L1 the same time/place you got your L3.

Worked for me. Must be 2003 - interesting to see how close to the rocket you’re allowed to be !
Maybe just where the video was taken from.
Nice flight.




Sent from my iPhone using Rocketry Forum

les said:

The link does not work...

But nice coincidence that I got my L1 the same time/place you got your L3.

Click to expand...

As long as you have a facebook account it should work.

Nick@JET said:

Worked for me. Must be 2003 - interesting to see how close to the rocket you’re allowed to be !
Maybe just where the video was taken from.
Nice flight.




Sent from my iPhone using Rocketry Forum

Click to expand...

In all truth of the matter we only had a 400 foot cable to reach out to the pad I brought to fly my rocket on. We were at the mod roc pads, but your right it was too close. One of the NEPRAH guys complained about that. Only, the rest of the club's BOD and the fact that we were all experienced rocketeers, (and crazy too), they let us launch from there as we were 400' from the rocket, the rest of the spectators were 500' like they should be.
I think that the fact that it was the first 'M' motor to fly on that field, and everyone wanted to see it fly, might have had something to do with it too.

Mdutch said:

As long as you have a facebook account it should work.

Click to expand...

negative. the post is missing or unavailable!

Eric said:

Its looking great. How do you physically break the connection between your Raven 2 and your pyro's?

Click to expand...

I was told the need for switches to break the connection to the pyro's was dropped.

I would check with your L3CC on the switches.

My L3CC was the one who told me.

"that requirement was removed around 3 -4 years ago. Now as long as your altimeter completely removes power to the charges when turned off you don't need an extra pair of switches to them. And almost all altimeters now meet that requirement if not all of them."

les said:

My L3CC was the one who told me.

"that requirement was removed around 3 -4 years ago. Now as long as your altimeter completely removes power to the charges when turned off you don't need an extra pair of switches to them. And almost all altimeters now meet that requirement if not all of them."

Click to expand...

Are you considering turning off the Altimeter as "disconnecting power" from the pyro's? Or is your switch inline with one of your battery leads?

When the magnetic switch is turned off. Everything is still "connected".
But what ever your L3CC signs off on is good. My powerperch plan was denied.

Sent from my VS988 using Tapatalk

My L3CC was the one who told me..... "that requirement was removed around 3 -4 years ago....."

Read the rules. It's there or it's not.... There should be no ambiguity.

FredA said:

My L3CC was the one who told me..... "that requirement was removed around 3 -4 years ago....."

Read the rules. It's there or it's not.... There should be no ambiguity.

Click to expand...

National Association of Rocketry Level 3 High Power Certification Requirements (Link to PDF)

2.4 The capability must exist to externally disarm all pyrotechnic devices on-board the rocket.
In this context, ‘disarm’ means the ability to physically break the connection between a
pyrotechnic system and its power source. Simply turning off the device controlling the
pyrotechnic(s) may not be sufficient.

Click to expand...