Shockwave 29: Finished!

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Aksrockets

Now with 8% more aluminum
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After a long Sunday of talking with my brother, Ive decided to take up a new project. The Mach-Mobile 2, replacing my Mach-Mobile 1 (pronounced automobile, minus the auto, plus the mach). The MachMobile2 will be 29mm minimum diameter rocket, built like a tank. The tubes will be 2 wraps of fiberglass and 3 wraps of 2x2 twill carbon fiber. The fins will be of my own creation, I will be pressing my own fiberglass sheet and laminating it with more 2x2 CF. I dont have plans for a nose cone, possibility a ShockWave 1.14in Fiberglass one.

This project is largely inspired by Jim Jarvis's Articles on Rocketry Planet and Tfish's videos. I will be following most of the steps the RP articles, including the epoxy coating and T2T carbon. Right now, I'm in the designing stage, drawing up Openrocket files, designing for maximum sexy-ness. Tonight, I might make the trip to ACE to see if I can find a good dowel for the mandrel.

Tonight or tomorrow, I'll order the CF, FG, and Peel-Ply from Aircraft Spruce.

Also, THIS IS A VIDEO BUILD!!!! You will see me do everything instead of me just telling you everything. I want to format it similar to Tfish38's videos. I will narrate the build as I go but I'll speed up the boring parts to make this more enjoyable. You might be able to help me more that way.

Most likely, this will be a long build, so go pop some popcorn. :pop:

So, without any further delay, Let the building begin! :D

Alex
 
A few more things.

I drew up the plans for where to cut the CF in study hall. After finding out how much CF I needed, I found the area af the CF and the fiberglass. Figuring the CF was $31 a yard and the FG was $10 a yard, I included epoxy and peel ply and got a price of $21 for the fins and airframe. Whoa. That didn't seem right. I checked my numbers again. Everything was included, CF, peel ply, fg, epoxy. Still, $21-25. There ya go guys! Everything but the NC and recovery for $25!

Another thing is, my family is moving. I will have little time to build In the next two months. I'll do my best, still this'll be a long build.

I ordered the Cf, peel ply and fg from aircraft spruce last night.


Alex
 
Not moving far, a few blocks away from my old house!

While on an orchestra trip to California, I drew up newer, sexier openrocket plans (at least in my opinion)

View attachment mach rocket 1.1.ork

Tell me what you think!

I will also be building a tower to eliminate the need of lugs or rail buttons.

My order of CF and FG came in while I was away. Looks good.

First flight might be on an H410Vmax at hellfire 17 in August :cool: Sims to about 5K at about mach 1.5. Zero to 1137mph in .4 seconds! (according to openrocket)

New name: the "SHOCKWAVE"

Alex
 
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I'm building something like this, only the el-cheapo version: a footlong 29mm phenolic tube with 3 rectangular airfoil fins and a nosecone. I designed and built a minimum-diameter ogive tailcone retainer so I can use motor eject, though I might end up not doing that for the planned H410 flight because it would early eject at 200 ft/s at around 9000 feet.

Some questions:
How do you plan on implementing a tailcone like that? The CTI 29mm tailcone closure doesn't taper nearly that much.
What are you using for deployment? (I plan to get a Telemini for tracking and deployment on mine, but CF will impede tracking for you)
Why is the streamer so small? OpenRocket predicts a 150-200 ft/s landing speed depending on the motor you put in (quite a crater that'll make!).

Also, if you can find a lighter nosecone strong enough for supersonic flight than the Shockwave, you would get significantly more speed. The Shockwave is kinda heavy.
 
Some questions:
How do you plan on implementing a tailcone like that? The CTI 29mm tailcone closure doesn't taper nearly that much.
What are you using for deployment? (I plan to get a Telemini for tracking and deployment on mine, but CF will impede tracking for you)
Why is the streamer so small? OpenRocket predicts a 150-200 ft/s landing speed depending on the motor you put in (quite a crater that'll make!).

Also, if you can find a lighter nosecone strong enough for supersonic flight than the Shockwave, you would get significantly more speed. The Shockwave is kinda heavy.

Sorry, I don't have the tapered retainer yet so I don't know the specs.
For deployment I'm using motor eject, tracking smoke and a pair of sharp eyes.
I will have several streamers on site, I'll just choose one depending on wind conditions

what would you suggest for the nc?

Alex
 
I don't have any alternatives to suggest for nosecones, other than making one out of balsa or something, I was just stating the fact. I'm probably gonna have to use a Shockwave because the extreme compact size of my rocket requires the tracker to go in there.
 
So far I haven't seen any videos. Something wrong?

Actually quite a few things went wrong.
I wont make a video for this post because I dont see the point.

I went to ace with my 29 3g casing to try to find a mandrel. I browsed around and found a 1in dowel that looked to be the same OD as the casing. It matched up pretty well, anyways. I took it home and wrapped it in plastic and made my fiberglass tube . Unfortunately, this tube was stuck to the mandrel. I filmed the process but will not post the video.

The I went to ace again and bought the same mandrel. This time, I took it home and wrapped it in parchment paper. I gave it 3 wraps of 6oz glass. After the epoxy cured, the tube slid off and the parchement paper peeled off easily. However the tube was to small for my casing #$@@**!!!!!!!!!!!!!.

Anyway, now i'm really pissed off. :mad::mad::mad:

CHANGE OF PLAN.

I do have a 29mm motor mount tube. I will peel off 75% of the outer layer on the tube. At this point, the tube will be very weak, flimsy and thin. I will wrap the tube in 3 layers of carbon fiber and voila! a 29mm carbon tube (well, almost).
This way I dont have to worry about the fiberglass getting stuck or small mandrels.

The catch is, the new tube is only 21in long, 8in shorter then the original tube. Still, it's stable and will work nicely.

Does that sound like a good plan?


Alex
 
May I ask, what made you think that 1" tubing would work as a mandrel for 29mm motors? 1" is 25.4mm.

You probably should have looked into getting a properly sized mandrel before even buying the materials for the rocket.

Anyway, the thin paper tube + carbon will probably work fine, just make sure that it's absolutely straight and still round after peeling off the outer layers. Are you using peel ply on the surface?
 
It's finshed. I only made one video but took lots of pictures, i'll put the video on first (making the tube) followed by the pictures.

Hows about a teaser....
IMG_4741.jpg

Alex
 
Very pretty.

I'm beginning to think this isn't going to be full of videos.

Sorry to be a hardass. You promised videos galore.

Bryce
 
Very pretty.

I'm beginning to think this isn't going to be full of videos.

Sorry to be a hardass. You promised videos galore.

Bryce

Sorry about that, videos are a pain in the butt to make! I've had every single video problem imaginable, my tripod broke, the camera needed a new battery (couldn't recharge) I spent several hours just TRYING to upload an hour and on top of that, our computer's memory was full so it deleted itself. Then about half an hour of editing and another hour of exporting, I spent twice as much time on the video then I did actually building! I realized that I couldn't build like this so I decited to make just one.

Sorry for the dissapointment.

Alex :(
 
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Looks awesome! When will it fly?

I'll put it up on an H410 vmax at hellfire 17. Should be a nice little pop.

Video is boring, just skim through it but it gives you a general idea....
[YOUTUBE]q4nK2G26kX8[/YOUTUBE]



Pictures to follow...

Alex
 
I expect about mach 1.3-1.5 ish and about 1 mile high. Some crazy acceleration, 0-mach 1.3 in .4 seconds (openrocket)

After the tube was done, it was time to make the fins, I set a peice of parchemnt paper on a book and gave it a generous coat of epoxy. Then, I laminated a layer of carbon fiber. After the carbon i put on 12 layers of 6oz fiberglass. After the fiberglass came another layer of carbon. I pressed more parchment paper on top of that and set another book on top of that. I placed about 80lbs of weight on top of that.
I got a nice, stiff carbon fiber-fiberglass sandwich. I took pictures of the entire process, unfortunately they were accidentally deleted.

I cut the fins out using a jig saw.

IMG_4688.jpg

IMG_4690.jpg

IMG_4695.jpg

IMG_4693.jpg
 
I cut out a fin guide using The Payload Bay.com. The fin guide is made out of a shoe box and worked nicely. I roughed up the bottoms of the fins and attached them with CA.
IMG_4702.jpg

IMG_4705.jpg

IMG_4710.jpg

IMG_4715.jpg
 
After that was the Chopped Carbon fillets. I mixed finely chopped carbon with proline thin epoxy resin and smeared it along the spot where the fin meets the BT. This created very strong (but ugly) fillets.
IMG_4718.jpg

IMG_4719.jpg


Alex
 
After the carbon fiber fillets came the cosmetic fillets. I wanted a black epoxy but did not have any thick proline on hand. So, I mixed super fine graphite with epoxy and used that. It's glass smooth and has a nice dark black color. IT smoothed out nicely and created good, clean fillets.

IMG_4739.jpg

IMG_4741.jpg

Alex
 
After the fillets, it was time for finishing.

I sanded down the tube, first with 220 grit, to remove the rough texture, I worked my way up to a 400grit wet sand.

After the wet sand I applied 3 coats of Rustoleum clear gloss with the following results:

IMG_4720.jpg

IMG_4750.jpg

IMG_4746.jpg


Still waiting on an NC
Alex
 
If you put peel ply on chopped carbon fillets, it keeps them smooth without them needing as much of a cosmetic layer on top.
 
If you put peel ply on chopped carbon fillets, it keeps them smooth without them needing as much of a cosmetic layer on top.

I would have never thought of that.
I kind of just wanted to try out the graphite/epoxy mix and I think it turned out quite nicely. Sure, Proline would be stronger but this is fine for now. The fins are ROCK SOLID also, not even the slightest wiggle. This thing is built like a tank. She'll look even better with a shock wave nose cone. I just got allowance (yes, i still get that, I'm 15) so I'll purchace one shortly.

I'll try again with some pics that didnt upload the first time...

IMG_4744.JPG


IMG_4722.JPG


Alex
 
You can also adjust the epoxy:filler ratio to be much, much much leaner on epoxy, keeping the fillet weight down while keeping the strength up.
 
Well, it's pretty much finished.
I received my shockwave 29mm NC. It's good quality, fells very sturdy and pretty smooth. No gel coat.
I spread some bondo on the high spots and primered with Rustoleum 2x grey. I gave it a coat of rustoleum 2x aluminum and it was done!

IMG_0420.jpg

I masked off the fin can and painted one of the fins aluminum with a little pointy thingy.

IMG_0406.JPG

I made my own decals with chrome monokote trim. I printed out what I wanted, taped it to the Monokote and used a hobby knife to cut out the letters.

IMG_0408.JPG

I dont think I did to bad. Well worth a few weekends and $50!
IMG_0401.jpg
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More pics in the next post!
Alex
 
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