The Noob Tube: Lvl 2 Cert Scratch Build

[user 26092]

Hello all,

My name is Shane and I'm new to the forums. I got started with rocketry in college. The team I joined regularly participated in the NASA Student Launch competition. After getting my hands dirty with HPR, I've now begun my own quest to continue building big and bad rockets.

I'm currently in the middle of building my first L2. I've designed it loosely off of the PML Callisto kit (which I got my L1 cert on).



"Low and slow" seems to be the mantra when flying for a cert flight. For that reason, I'm looking at flying a J280. Sims show the Noob Tube hitting around 2900ft which is the lowest I think I can get for 54mm motor.

I was looking for simplicity when designing the rocket so I decided to omit an ebay and hope for the best using the piston ejection. I'll be flying a 50" chute from Top Flight. According to OpenRocket, I should weigh about 7lbs at burnout but I'm willing to bet I build the Noob Tube heavier than is simulated (or I can add some weight to make it so). At a decent rate of 20 fps, I'm looking at about 2.4 min of drift time so windy conditions will be considered before I decide to launch.

I'll be adding pictures and more commentary of the build in future posts.

Any comments and feedback is greatly appreciated.

 

[qquake2k]

I'll be watching with interest. I did kind of the same thing for my L2. I upscaled an Estes Shadow with LOC 5.5" tubing. I think it weighed 11lbs on the pad. I decided on a 38mm motor mount, and used a CTI J400 for my cert flight. I built it zipperless with a 58" chute. I have since put a 78" chute in it. It was a fun project.

 

[chris m]

Man from the title I was thinking it was a tube fin rocket . My L3 is a tube fin monster

 

[Handeman]

Welcome to the forum Shane.

I glad to hear you're going on you own for a cert after the SLI experience. We had three SLI team doing launches at our last club launch. I'm always amazed at the technology and engineering they put into their rockets. I'm also surprised and amazed at some the questions they ask because they don't always understand some of the basics of flying hobby rocket and usually don't have the experience with rocketry when they start flying large L2 SLI rockets.

Have you had many L1 flight on your Callisto? I've been flying mine since 2003. It's a great rocket. The more experience you get with that, the better and easier your L2 will be.

If you don't mind, a couple of suggestions on your L2 design. With the piston, make the shoulders at least as tall as the BT diameter. Also, put the bulkhead in the piston to the aft end of the piston, not the forward end like PML has you built them. That won't make a big difference but if you search, there are numerous threads and websites that explain the advantages of having the piston bulkhead aft.

With a weight of 8 lbs I'm assuming the rocket is fiberglass. You shouldn't have problems with the piston, just keep the inside of the BT clean. If it does use LOC type BT, I suggest you spray paint the inside of the tube before you glue things together. Getting a coating of paint on the inside will make the piston work much better for much longer. You'll just have to be more selective with adhesives if you paint the inside of the tube before assembly.

The other suggestion I would have if you are going to fly with motor ejection is to use a Jolly Logic Chute Release. It really makes high flights with motor ejection land much closer to the pads. It's just as effective as DD and in some cases, even more. Just practice with the JLCR before the cert flight. I use on in my Callisto and 3K flights are no problem.

The last, if you do intend to make this rocket conventional DD at some point, I would design it with the DD and then drop back to using just a nose cone. It will make it much easier to add the DD later if it was designed for that from the start.

Anyway, good luck and best wishes.

 

[Bat-mite]

If you don't want to do dual deployment, consider a Jolly Logic Chute Release. Dramatically increases your chances of getting it back.

 

[user 26092]

I'll be watching with interest. I did kind of the same thing for my L2. I upscaled an Estes Shadow with LOC 5.5" tubing. I think it weighed 11lbs on the pad. I decided on a 38mm motor mount, and used a CTI J400 for my cert flight. I built it zipperless with a 58" chute. I have since put a 78" chute in it. It was a fun project.

Thanks for the support and great looking build! I'm hoping my finished product will look as sharp when I'm finished.

Have you had many L1 flight on your Callisto? I've been flying mine since 2003. It's a great rocket. The more experience you get with that, the better and easier your L2 will be.

Sadly, I only had two flights on my Calisto before it became a victim to the apple orchards of northern Ohio. Searched for a couple of hours that day and found about 5 other rockets while I was out there. Everyone was sad for my loss but very grateful I was able to save them the effort of finding theirs.

If you don't mind, a couple of suggestions on your L2 design. With the piston, make the shoulders at least as tall as the BT diameter. Also, put the bulkhead in the piston to the aft end of the piston, not the forward end like PML has you built them. That won't make a big difference but if you search, there are numerous threads and websites that explain the advantages of having the piston bulkhead aft.

I remember seeing this in some older threads when I was researching piston ejection. Unfortunately I assembled the piston this past weekend in the conventional PML method. I can't believe I forgot. I'll be sure to remember in the future though.

With a weight of 8 lbs I'm assuming the rocket is fiberglass. You shouldn't have problems with the piston, just keep the inside of the BT clean. If it does use LOC type BT, I suggest you spray paint the inside of the tube before you glue things together. Getting a coating of paint on the inside will make the piston work much better for much longer. You'll just have to be more selective with adhesives if you paint the inside of the tube before assembly.

I've taken PML phenolic and added a fiberglass layup. I'll be sure to give a thorough wipedown of the tube interior before launch. Would you recommend painting the inside of the PML tube? I'm not familiar with LOC products or their similarity to PML.

The other suggestion I would have if you are going to fly with motor ejection is to use a Jolly Logic Chute Release. It really makes high flights with motor ejection land much closer to the pads. It's just as effective as DD and in some cases, even more. Just practice with the JLCR before the cert flight. I use on in my Callisto and 3K flights are no problem.

I'll highly consider the Jolly Logic. The price is a bit steep but not as much as losing the entire rocket.

As you mentioned before, we learn to build really great rockets in NSI but we miss a lot of concepts since some of us are fairly new to the hobby. I figured the forums would be a great place to grow as a rocketeer so I really appreciate the feedback.

 

[user 26092]

So here are the majority of my materials for this build.



I decided to go with mostly PML components since it is what I am familiar using and comfortable working with.

The airframe is 4" x 48". The cost wasn't much more than a 3" airframe and included some features I was looking for in this build such as increased drag for a lower altitude and more space to work with when installing the motor tube and centering rings.

The additional components pictured include 4" plastic nosecone, 54mm motor tube, 50" parachute w/ kevlar shock cord (considering switching to thicker nylon tube for fear of zippering), 54mm HAMR retention, and 1/8" G10 centering rings and fins.



In addition, I purchased fiberglass sleeve and heatshrink from Soler Composites (The 3" sleeve is for a friends build). I've done CF layup for our SLI projects and wanted to try my hand at doing composites on my own. I also think the added strength will be needed for future flights if I decide to fly bigger and badder motors.

If everything goes together as I imagine it, the final product should look something like this:



I've spent the last two Saturdays doing my composite layup and beginning some assembly. Once I compile my photos, I'll be sure to share my progress.

 

[qquake2k]

Looking good. This is the nylon webbing I use in my bigger builds.

https://www.rei.com/product/610111/bluewater-58-climb-spec-tubular-webbing

 

[user 26092]

It's been a few weeks but I've been working off and on for the build. Here's some pics from the fiberglass. The heat shrink tubing gives a great finish.

 

[NattyDread]

At that altitude, and a little wind, clouds, you might lose this rocket too. You could get a motor tube reduction kit and run a 38mm. That would bring down your altitude for the cert. In my experience, you need a dual deploy option above 3000 feet so you don't loose it. Much above 3000, or larger rockets w larger chutes, a gps will get you your rocket back.