The Aliens are coming . . .

[EMiR]

Howdy from the Land Down Under…

I'd like to share with you guys, if I may.. A little 3" Carbon Fibre build of mine called…..

The Alien Rocket


Desktop Background - click for full size (1600x1200)​

This is the third version in a series of designs for the Alien Rocket, it’s a design I came up with over 3 years ago, and has evolved over the years into this latest version.
It started as a little glow in the dark 2 stager using 18mm/24mm engines, before growing up, into a 2.5” single stage, single deploy rocket. And now… It’s big brother had arrived, and means business…

Some images of the Alien evolution..

Mini 2 stage Alien

2.5" Single Stage Alien - Alien v1

If you’d like to see more the alien v1 (2.5”) build, you can check it out at - Alienworks Rocketry


Back on it’s big brother..
Here’s a little list of parts I’ll be using for the build..

Scratch Build Parts;

2 - 3” x 30” Carbon Fibre Body Tubes (pre-cut), 5 layer, 7.7oz 2k Twill
1 - 38mm x 25” Carbon Fibre MMT (pre-cut), 5 layer, 7.7oz 2k Twill
3 – Aft Fins – Ply wood and Carbon Sandwich. (6 carbon layers, 2 ply wood layers)
3 – Forward Fins - Ply wood and Carbon Sandwich. (6 carbon layers, 2 ply wood layers)
2 – 3” to 38mm Centring Ring - Ply wood and Carbon Sandwich. (6 carbon layers, 2 ply wood layers)
2 – Av-Bay Bulk Heads - Ply wood and Carbon Sandwich. (6 carbon layers, 2 ply wood layers)
1 – 3” x 7.5” AV Bay tube, 5 layer, 7.7oz 2k Twill
1 – 25” X-Form Drogue Chute – Rip-stop
1 – 50” Octagonal Main Chute – Rip-stop

Off the shelf Parts;

1 - Aeropack 3” to 38mm Clear anodised Boat Tail Retainer
1 – 3” 5:1 Fibre glass nose cone
2 - 120” x 1” Nylon Shock Cords
Misc Stainless steel eye bolts/hardware.
2 – 10x10 Rail Buttons
2 – Raven Flight Computers
2 – Raven Screw arming switches
2 – 12v Lipo Batteries

The Design - 3" CF
This has been a very challenging design to say the least, being it’s odd shaped multi fin design, it posses quiet a challenge in keeping CP/CG relationship good, whilst keeping the look of a design / Fin shape and size balanced.

So after many, many hours of playing around with Fin shape/sizes, this Roc-Sim Screenshot is the closest
to what the finished rocket will be..
(I will be posting later, pictures of differing fin shapes)

Here’s what I would expect the final assembly stage build to look like, (Post finish coats and Graphics)

So like me, I’m sure there are many of you who get just as much enjoyment out of building such creations, as watching them launch.
The following posts of the build process was taken of a period of 12 months, and I must say I have enjoyed every minute of this build, What a great hobby we are involved in.
To get such enjoyment from building such things, and then the icing on the cake, being able to watch them launch..
Fantastic..

On with the build..

-------------------------
Ashley Stonehouse (aka EMiR)
TRA L2 - 12474
Brisbane, Australia

Alienworks Rocketry

 

[JAL3]

You have a think of beauty there.

 

[troj]

That's a really slick design!

-Kevin

 

[UPscaler]

this thing just screams bright green LEDs

 

[EMiR]

To start, First of I like to say a big thanks to Jim Jarvis, for his outstanding Guide to using Carbon Fibre in rocket construction.
It was a truly an inspiration to me, and gave me the motivation to produce this Rocket along the same lines.
Thanks Jim

Link To Jims building with Carbon Fibre Guide


This is my first Carbon fibre built rocket, and not quite up to doing a tip to tip, as in Jims build, I’m sure with a little more practise, I may get to that level of technique.
At this stage I’m happy with the way the alien has come out. For a first go..
So in posting this, I hope this will inspire others also to try some more complex rocket build techniques.
The only hard bit is trying…


First part of this build, is of course gathering the bits needed. This post is about making the parts need for the build, and how I went about it.

Rolling the Tubes

Well a good mandrel is the first place to start with any scratch built tubes, In this case I went with Randy’s from Always Ready Rocketry - beautiful full length Blue tube Couplers (48” long).

I made up a stand from Aluminium as a mandrel stand, as its important to keep the carbon fibre strait as it goes on to the roll..
The releasing layer I used in this was Grease proof paper (baking paper). It was wrapped once around the mandrel, and butt joined using a strip of scotch tape. As described in Jim guide.


First tube I rolled, was the 38mm MMT, As this is not seen, it’s a great place to have a bit of a practise run, of getting finish line of the carbon strait.

I used a Small paint roller to apply the epoxy, and coated about ½’ at a time.

Martials used in this part;
7.7oz 2k Carbon Fibre Twill
Araldite 3600 epoxy

MMT Tube is 3 Layers thick, and ended up with a 1mm wall thickness

38mm MMT

Happy I’ve got a feel for rolling CF, I proceeded with rolling up the Body tubes..

Martials used in this part;
7.7oz 2k Carbon Fibre Twill
Araldite 3800 epoxy

Body Tubes are 5 Layers thick, and ended up with a 1.7mm wall thickness
2 layer of peel ply was added, to compress the layup.
Then the Whole lot went into a heat box for a few hours..

The Layup

2 Body tubes ready to go

Tubes have had a thin coat of epoxy after the peel ply was removed, to protect the carbon, and as a sanding layer for later in the build process.

Next is the Fin Stock and CR's

----------------------------
Ashley Stonehouse (aka EMiR)
TRA L2 - 12474
Brisbane, Australia

Alienworks Rocketry

 

[BsSmith]

That design is amazing!

I just found inspiration for my next scratch build.

 

[EMiR]

Fin Shape and Design

So after many hours in the Sim playing with fin shapes, it was time to see them in real life.
These were the 2 best shapes of about 10 or so.

I decided to go with the fin on the bottom of picture, though being a bit more lower in height and moving CP forward slightly,
I felt it had the best look..

Fin Design / Template

Now I have my templates, I proceeded to make up the Fins..
The fins are made from a sandwich of 2 layers of carbon, 1 layer of ply, 2 layers of carbon, 1 layer of ply and 2 layers of carbon.
Compressed between 2 sheets of MDF and clamped, then heated in a hot box for a few hours.

Image of the Carbon/Ply layup.

I chose Liteply over G10 sheets, as weight thing, as the rocket design has a close CG/CP relationship,
Every bit of weight I can save in the lower section, the better.

Picture below is 1 fin that just came out of the hot box, with rough edge still on, and 1 that has the edges cleaned up.

The inner ply layers were cut correctly, off the template, the Carbon layers
were made slightly larger, this is so that there was no change of carbon
layer not reaching the edge, and made it easier when cleaning up the edges,
and to know to stop when the ply was exposed.

Fin Stock

So after months of cutting templates and doing layup’s, heres the complete body section parts needed to start assembly.

Parts Stock

Ready to start assembly…

-------------------------------------

 

[EMiR]

[Assembly]

Like all kits, this first place to start is the Fin can..

First up, I will make up a Fin Guide, to get the Fins nice and square off the tube.
Also this makes marking the Fin Slots in the body tube a lot more accurate.

I’ve seen many ways of getting Fins square, but for me this is the only true way.

Making up a guide like this saves any change of getting it wrong.

A quick way of checking your guide is symmetrical and square, is lay it on a piece of paper draw an outline of the cuts, and then rotate the guide it to check that all the slots line up with paper after each rotation, do a rotation for number of slots you have.

If they all line up after each rotation, you’re good to go.

A good fin guide can be as simple as a piece of cardboard. And will give you great results every time.

The one in the picture is the 3rd one I made, the first two I wasn’t happy with the line up, as per the method of checking I just stated. They were a few 100th of an inch off.

The 2 failed ones became the rocket stands, as seen later.

Fin Jig

Fin Jig completed

Time to mark up the body tubes, and prepare to cut them out.
Here the square edge set up ready for the Dremel with a cutting wheel.

Slots Marked

I would have preferred the method of a router on a slide setup, with the tube in a box. But being carbon, I would say the router bit would have lasted a whole of 10 seconds.

So I opted for this method, and as you can see still gives a pretty strait cut.

And you guessed it, it made hell of a mess, Carbon dust every where,
Very important to have a good quality breathing mask and goggles on during this type of activity, your eyes and lungs full of carbon is not a good thing..

Cutting Slots

On to the Fin Can assembly,

Being a Carbon MMT, and the fact carbon is a great heat transfer, all parts that attach to it will be done with JB Weld, to ensure that the heat coming off a live motor fire, will not soften any of the stress points.

Starting with the forward Centring Ring,
First I sanded down the top 1” or so until the carbon fabric was exposed
Then I used JB weld for the bond, and gave it a heat cure..

Forward CR

Then attached the middle CR in the same fashion.

Moved on to preparing the fins of attachment, here’s giving the Fin edge a cross hatch with the Dremel and cutoff wheel. This give the JB-Weld a nice grab on the fins.
And of course sanded the MMT down into the carbon where the fins touches.

Fin Cords Cross Hatched

Time to start tacking on the Fins, Got out the trusty fin guide. And started attaching.
I used JB-Weld, and enough not only to give a good bond on the cord edge, but enough that it overflow out the side, and forms a small fillet ether side of the fin.

I did this whilst the MMT was out, pushed on the fin, then slid the whole thing into the Body tube and guide.
So there was no change of getting JB on the body tube slots, and sticking the MMT in.

Fin Attachment

I slotted the middle CR and Fin edge to line up with each other. This helped to keep the Fin edge in place when attaching to the MMT.

Tacking on is complete, the next part was, internal fillets, Here I used Carbon fibre Strips over the small JB weld fillets, with a West systems resin and milled glass mix, to wet out the carbon and to fatten up the fillets

Internal fillets

Last thing to do is get the Shock cord on before it gets glued in. being a 3” tube, not really shown in the picture, I used a little piece of off-cut from my Carbon-ply sandwich to beef up the anchor point.
Welded Stainless Eye bolt used and JB welded in place.

Lower Shock Cord

---------------------------

 

[EMiR]

Posting some more in the next few days,

Thanks to guys already posted for the great replies..

 

[epickett]

That's a cool looking bird!

 

[Sandy H.]

Awesome design and great build so far!

Sandy.

 

[Brent]

Very Cool!

 

[EMiR]

Time to glue in the can,

A little step I missed getting a picture of, is I cut the corners off the middle centring ring,
So I could get a good fillet all the way down to the forward CR, so I just cut enough off
The CR to let the epoxy flow past, and small enough the fillet would back fill the little bits I cut off.
I did this so I didn't have to do ejection fillets

I knew the epoxy had reached the forward CR, when I saw it start leaking in that area,
I let it pile up a bit, and rotated around a bit to get a fillet on the backside of the forward
CR, then tipped the rocket back, until the epoxy started to run back out of the rocket, then
laid flat until cured, did 2 internals at a time.

This was a West Systems and Milled Glass mix, and was the consistency of honey.

internal fillets

I got the Fin Can glued in, and the forward fins tacked on as well,
The forward fins are half the cord length as through the wall, for about 1/16”
Then coat in the inside with West systems epoxy and Chopped Carbon.
Ready for the external fillets..


Internals done

I started with the forward section, and did my external fillets like most people here on
the forums, I taped off, and used a piece of balsa with a rounded end to the size I wanted
the fillets to drag across to give me a nice clean fillet.

I used West systems, Milled glass, and a black epoxy die.
Mixed up to about the consistency of peanut butter.
The best way to check if you have your epoxy/milled glass mix right, is
get it the point, where it will not drip/fall of your mixing stick.

Once all the fillets were done, I bevelled the Fins edges, and gave the
whole thing a good sand down with 120 grit sandpaper, being careful not
to sand into the carbon.
But ensuring I have no shiny bits anywhere..
As Jim points out, sanding is best done a boot polish style, across the tube
rather than sanding up and down the tube, this will ensure your tube stays nice and round.

Then gave it a good wipe coat of west system epoxy

Though it not showing up in the picture, this stage still has a lot of
scratching still visible from the sanding with heavy paper.
This is the first of about 4 sand and coat processes.

--------

 

[EMiR]

Time to make the AV Bay,

As you can see I beefed up the tie points with strips of the Carbon/ply leftover from the CR/Bulk head lay-up.

The tie rods and Eyebolts are 3/8” Stainless, the sled is G10 with aluminum slide tubes.

AV_Bay

Hers the booster section after it first good sand down, with 120 grit paper Dry sand,

Booster 1st Sand

After 2 thin wipe coats of epoxy

Booster 1st Coat

Next will be adding the Bevels to the leading edges of the fins, then a another all over sand with 400 grit wet and dry paper.(Dry sand).

Another thin wipe coat of epoxy, then sand down with 600 grit Wet & Dry, (Wet Sand),
And finally a another 2 thin wipe coats, to bring up the shine


Booster Pre-Finnish

This is the Pre-finish stage..

I still have the Tail cone retainer mounting to finish off, the AV bay,
Launch lugs and of course the graphics. Then its final Clear Coats.

Also Completed the drogue and Main chutes

Chutes

--------------

 

[EMiR]

Did I bit of work today, mounting the Rail Buttons, and preparing the the back of the rocket for the Tail Cone assembly.

Rail buttons - I glued in a strip of Carbon/Ply, and added T-Nuts.

I've added 2 button at the rear of the rocket, to ensure good speed before the rocket leaves the rail.

total is 3 lugs, 1 forward and 2 rear.

Also Started work the AV-Bay...

Launch Lugs

AV_Bay_Sled

----------------------

 

[G2Rockets]

Oh shoot, I just realized that there is something very wrong with your rocket.
I hate to be the one that points it out, but feel I must. The problem is that I don't have one.

I couldn't resist. VERY NICE!!!!!!!!

John

 

[EMiR]

hehehe, well you could have 1,

if your hassle Randy over at Always Ready rocketry, I do believe he may have some 3" blue tube versions getting kitted up.

 

[epickett]

Time to make the AV Bay,



This is the Pre-finish stage..

I still have the Tail cone retainer mounting to finish off, the AV bay,
Launch lugs and of course the graphics. Then its final Clear Coats.

--------------

Dude, that is BEAUTIFUL!:clap:

 

[kelltym88]

What a great design! That's gonna be a great flier. Thanx for sharing.

 

[Wiley]

Those are some gorgeous tubes! And this is your first time at it:eyepop:? Just a quick question. What type of epoxy did you use to make these tubes. I'm leaning heavily toward using US Composites epoxy for my composite parts. If the epoxy you used wasn't US Composites epoxy, would it work just as well as whatever you used? Thanks!

 

[rockie]

Thats one of the colest and original rockets i have seen. Nice job !

 

[EMiR]

Those are some gorgeous tubes! And this is your first time at it:eyepop:? Just a quick question. What type of epoxy did you use to make these tubes. I'm leaning heavily toward using US Composites epoxy for my composite parts.

I used Araldite LY3600 CI Resin with Aradur 3600-2 CI hardener
To do the tubes.

If the epoxy you used wasn't US Composites epoxy, would it work just as well as whatever you used? Thanks!

Being in Australia, we dont get US composite stuff down here, So I can't make a real basis, if its any thing like west system, I'd say you could use it for a carbon application like this, maybe not that best system for it though.

 

[EMiR]

Both Ravens' have arrived, and I a little time to do some more on the AV bay this week...

The 2 Ravens mounted... as well as getting the 2 LiPo Batteries sourced. (7.4v 800mAh)

I used little T-Nuts and Screw off too.

 

[Bravo52]

Absolute best design I've seen in a while. Stunning. Excellent design. Excellent craftsmanship.

Keep posting. Please!

I want one.

 

[n3tjm]

Wow, amazing design. I think it looks cool just the way it is . What do you plan to fly it on for its first flight?

 

[EMiR]

It would be nice to launch it on a CTI, Green or sparky motor.
but unfortunately here in OZ we can only get Aerotech motors, and we're limited to 1 supplier.
And being he is the only supplier has an attitude to match

So it will come down to what ever Aerotech RMS I can get in 38mm
most likely a J350W

How lucky you Americans are..
having such a great choice and availability.

 

[UPscaler]

It would be nice to launch it on a CTI, Green or sparky motor.
but unfortunately here in OZ we can only get Aerotech motors, and we're limited to 1 supplier.
And being he is the only supplier has an attitude to match

So it will come down to what ever Aerotech RMS I can get in 38mm
most likely a J350W

How lucky you Americans are..
having such a great choice and availability.

Come visit some time. May I suggest the black rock desert in Nevada? XPRS. That way I can see this beautiful bird

Also has a 100,000 foot (not a typo) waiver. So you can fly it on all the high thrust heart pounding motors you wish to

 

[EMiR]

I certainly will, have been meaning to come to the States for awhile now.

Come, check out some of these big launches you guys have.

I'll have to pull my finger out, and try and line it up with a shuttle launch.
before they are gone ...

 

[UPscaler]

I certainly will, have been meaning to come to the States for awhile now.

Come, check out some of these big launches you guys have.

I'll have to pull my finger out, and try and line it up with a shuttle launch.
before they are gone ...

I would love to see a shuttle launch as well.

-Braden

 

[bandman444]

I couldn't find a rocksim file on this thread? Have you made one? I would be very interested in a 5.5" upscale? Bluetube?

Amazing design.