6 shooter 2.0

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Lister

Fresh out of Stasis.
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Feb 26, 2014
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A while ago I scratch built a 6 fin 54mm aft section that transitioned to a 75mm payload bay and nose cone with a 38mm MMT. Looked like a big RPG. It had its maiden flight last weekend and is now MIA, but it flew extremely well and looked pretty cool so I thought I would build another one with thin wall components to keep the weight down so I can get a little more speed out of it. Here are the adapted sims of the new version. The 54mm tube is a bit longer and between the nose and transition is now some 75mm airframe where it was just a coupler and HED so now I can use a 3" nose cone with an AV bay inside it. Will also use some 1010 rail buttons with some 1/4" launch lug and a long bolt for the standoff which is what I did on the first one of these rockets.
LNR 6Shooter (isis killer)1.0 wireframe.ork.jpg
LNR 6Shooter (isis killer)1.0.ork.jpg

here are a couple of photos of 6 Shooter 1.0 on its first/last flight last Sunday on a CTI I255RL. Thinking an I303BS would be very cool in the new one.
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Seeing as I have the mandrel for the 2"-3" transition and the 3" nose cone it should be alot easier to make this one. All the parts will be made from west systems 105/206 with a 287gsm plain weave and a 290gsm crowsfoot weave. The crowsfoot is great for corners and for conforming to tight shapes and it has a much tighter weave so it works well as final layer on the parts. Also its perfect for alo doing a tip to tip layup on the fins and for making 1/4" FG launch lugs by wrapping a waxed 1/4" metal rod with the crowsfoot cloth as it conforms to the tight corners really well compared to plain weave of the same weight which can be tricky in those situations.
 
Just dusted off the mandrels for the nose cone and transition and found another 3" nose cone already made, just needs a wet sand, coupler attached for shoulder and a tip made for it.
Also have some 2" & 3" airframe that just needs a coat of epoxy and a wet sand. so I only have to make the 2"-3" transition, a 38mm MMT and the 1/4" FG launch lug to use as the stand off for the 1010 rail button.
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The transition mandrel has been sanded to 400grit and then coated with 5 coats of wax to the mandrel as it was turning in the lathe, I leave 20 minutes between coats of wax and make sure that none of the wax is in clumps. I just use a cabinet makers wax thats a mixture of Beeswax and Kanuba wax, doing it this way I just need to give it a few taps once cured and then tap the mandrel out and clean up the inside of the part with wax and grease remover prior to bonding anything to it.
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This is the way I make most of my parts, it allows me to make them as thin as I want and means I can put the cured part on the mandrel into the lathe to sand it back and once satisfied its got no low spots and is a uniform thickness I add another layer of epoxy and when its cured I wet sand it down to 2000grit for a great finish. I will use the transition to show how my parts are done step by step.
 
Decided to change the fin design a bit, this design was chosen to keep the stability above 1.5calibres when at mach 2, the other fin design was dropping the stability margin to .7 at those speeds. This rocket will only be getting to those sorts of speeds when it has the 54mm MD booster added to it.

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does anyone have a suggestion of where I can find some aluminium tube with an ID of 1/8" thats 500mm - 1000mm long? Need something to mount between the 38mm MMT and the 54mm airframe that I can feed an e match through for airstarting when it has the booster attached :cheers:
 
Arrow shafts or dome tent poles might be an option.
Some florist's use a plastic tube for balloons and such. That's what I used in my darkstar 2 stage. Is there a reason you want aluminium?
Pushrod sleeves from the hobbyshop are another option.
If a shorter tube can be used then old telescoping antennas give you a few sizes.
Old TV antennas can also be a good source of aluminium tube.
 
I have some irrigation pipe that would work but I didnt think the plastic would hold up very well with the heat from the motor, which is why I was thinking aluminium.. the arrow shaft might be the winner, the other option was to use some 1/8" rod as a mandrel and making a FG tube with it. Think an antenna would be a bit short for this as it needs to come upto the neck of the transition.
 
RC shops should have appropriately sized CF tube. Heat shouldn't be much of an issue as IIRC all certed motors have the same surface temp. limit.
 
I have to head into town this week so I'll see what the hobby shop has, from memory they have aluminium, brass and CF tubes but im not sure if they would be long enough.
I have plenty of CF arrow shafts that are no good for archery any more so I use them in my rocket builds.. they are great mounted on AV bay sleds for the 1/4" or 6mm all thread to pass through. Just measured the arrow shaft and it will just fit between the MMT and the Airframe. I'll still see what the hobby shop has but if I would rather try and get away with not buying anything, Imy rockets all need to be built with at least one bit of scrap and a hammer must be used in the construction of my rockets... thats how I got my RAG membership (rough as guts) :bangpan: :gavel:
 
Just wet sanded the 3" nose cone down to 2500grit on the lathe, much easier than spending two days doing it by hand. This nose cone will be painted, alot of the others I have made had the epoxy tinted and the part polished to the point it doesnt need paint but cant be stuffed with that amount of work for this rocket :cyclops:
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does anyone have a suggestion of where I can find some aluminium tube with an ID of 1/8" thats 500mm - 1000mm long? Need something to mount between the 38mm MMT and the 54mm airframe that I can feed an e match through for airstarting when it has the booster attached :cheers:

Yuuuupp........ shown on 54 airframe with 38mm mount. Not Al, but steel...... Brake line from auto parts store, actually for YOU domestic, for us I ask for Foreign.

Since your already foreign...guess that make it domestic in OZZ...LOL

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Showing actual 2-stage build thread here for 54 to 38..motor:

https://www.rocketryforum.com/showt...stage-build-Vindicator-JR&p=552250#post552250


Good luck
 
Thanks CJ, brilliant idea. I'll drop round to my neighbour (scrap merchant) and pilfer a brake line that will fit this little beast. Why does it make a difference if its imperial or metric, are they greatly different in size?
 
That will make it alot easier, having 6 TTW fins on a 38mm MMT means there isn't much room between them for the tube to pass through.
 
My next door neighbour has a scrap metal yard containing 100's of cars. I needed some metric brake line to run down the gap between the 54mm airframe for the igniter to pass through for when it has the 54mm MD booster attached. Had to straighten the brake line and clean it out, quick wet sand and its as good as a new one.

I had some 1" wide kevlar from missile works so figured I would give it a try as the Y harness for this.. much easier to attach and about twice the strength of the strongest braided kevlar from emmakites.com and it looks cool.. does anyone know where to get the thick kevlar strap that is more like rope?

Will upload photos of the fins and all the parts in the next day or so.
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Thought I should share the before and after for the brake for anyone that wants to save a few $ by using second hand brake line.. I'm sure there are easier ways to do it but I'm pleased with the result.

Brake line was taken off a car so it required a bit of work to get it straightened and ready to be used on a rocket.. After I got the big bends out by hand I drilled a hole through the core of a 2.5" long piece of dowel, the hole is a poofteenth bigger than the brake line. If it was the exact size of the brake line it wouldn't have been able to get the line through it as the line was wonky.

took about half an hour but by moving the dowel up and down the brake line until it was fairly straight.
Then I placed a length of fencing wire up the middle of the line just to add some strength to it and clamped it into a drill and used my dowel tool to run up and down the line while it was spinning in the drill, I had to support the other end by using a 1/4" launch lug while I ran the drill and used the dowel. Otherwise it wanted to bend.

Then I gave it a wet sand with 600 grit then went over it with some steel wool. Where it meets the CR's I roughed up the tube with 180grit to help it bond and used chopped Kevlar and CF which has given me a solid bond. As you can see the line was quite wonky when I got it home and the results speak for themselves.

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Transition has been made using 4 layers of 287gsm plain weave cloth with a 5th layer of 290gsm crowsfoot weave, as you can see in the photos the crowsfoot weave has a tighter weave and the weave pattern makes it conform to curves and edges much better than the plain weave. The crowsfoot weave is the cloth on the left and the plain weave is on the right, its quite different and is easy to work with.

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I used red oil based enamel paint to tint the west systems 105/206. after the epoxy was mixed thoroughly I add the hardener weight -20% and lay up the part. Then when its cured I keep it on the wooden mandrel so I can sand it back on the lathe. Once I have it to the point where there are no high spots and its an even thickness (easy to tell on the lathe), I tidy the ends up with a hacksaw while the lathe is spinning and take it out of the lathe. Then I pop the mandrel out by placing the wide end on a section of 3" tube (the mandrel fits inside the tube so it acts as a guide) and tap the other end of the mandrel which breaks the seal between the waxed mandrel and the FG part and they separate easily.

then I mix up some more tinted epoxy and add some wests 411 microspheres and paint it on to fill in any low spots or dimples in the FG. I make the layer a bit thicker than needed as I will be putting it back on the mandrel and wet sanding it down to 2500grit which gives it a polished finish.

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Got all the parts done for the 6 Shooter. The nose cone tip is turned from an old Red Gum railway sleeper the shoulder of the tip has a hole/slot in the side of it to allow a 6mm nut to be epoxied into it for the 6mm AllThread to screw into which passes all the way through to the end cap on the nose cone shoulder and has an eye nut screwed onto the end to attach the shock cord to.

Now I just need to make the standoff for the rail button, attach the aft CR (did internal fillets and filled the cavity with expanding foam) And then attach the retainer and give 'er a lick of paint and its go for launch.. and then comes the 6fin 54mm MD booster :point:

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Got the 6 Shooter wet sanded to 1200grit and primed. Once the primer is dry I'll give it another wet sand and then apply the white, and again wet sand, then the red or purple (still deciding on the colour) and a wet sand.. finally the decals will go on before a few coats of clear that will also be wet sanded but down to 2500grit.

Hopefully I will have it ready for the TRAAU (Tripoli Australia) Launch this weekend :fly:
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First white coat is on :w:

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Cheers Bat-mite. I like this design a bit more than the first version of it.

Here it is with the red paint on, going to use a metallic charcoal on the transition. The photo of the fins is to show the bevel on the hole in the fins.. sort of like a reed on a woodwind instrument. Just an experiment to see if it whistles as a result.
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Thanks, hopefully with the 6 fin booster it will look even meaner :cyclops:
Im sending the revised sim to a couple of rocketeers in the u.s so you guys may get to see a couple. Only tricky bit is the transition, mine is made on a wooden mandrel that I turned on the lathe (waxed and then wrapped in FG) and I dont know of any off the shelf long transitions..?
 
I like the whistle idea - I'm going to have to try that on my next rocket!
 
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