1/3 Scale Nike Tomahawk build

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Yesterday, I got another set of fillets down on the Nike.

Finished cleaning up fin slots on the tomhawk, sanded the fins. Sanded the motor tube to accept the 54mm fastback retainer. Drilled centering rings up for brake line conduit, and notched the top two out for recovery harness and cut harness to length, followed by a check fit to make sure it came out the top. Figured out all the spacing Also checked the fit of the coupler in the aft end of tomahawk to ensure clearance of a ematch wire to make sure it would clear with the coupler installed.

Started drawing the tomahawk in fusion 360. Modeled the motor tube, rings and conduit, and made a spacer to tack the centering rings in. Got it printed as well. B243D062-508B-4EA7-97BB-E0B5870D2A27.jpeg3B58CCCC-7D34-4B4E-8C9B-A56822D5C13A.jpeg6FEE55E1-A410-4CBF-9B86-4C4575F9E814.jpeg
 
Today I got the 3rd and 4th set of fillets done on the Nike portion.

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Then worked on tomahawk section. Printed a fin jig for the sustainer on the prusa. Got middle and upper centering rings tacked on. I then cut the brake tube conduit to proper length. The harness was then threaded through the rings, slipped in the roll pins. A final fit check of the motor tube was conducted with the fins in, and checked all clearances with the aft cr in and made sure I could get the conduit in. Checked Al clearances with the retainer and coupler in the back to make sure everything was kosher. Pulled the motor mount out and epoxied everything together. Lastly, drilled and installed aft rail button as it will be pretty tight after the motor can is in. 5F23922F-7381-497B-9537-EB37ABBDA120.jpeg6C214C24-1047-4375-BBB7-EBBE4BA0BCA3.jpegD1CE28F2-D690-44F8-B0AB-2033B5096E3C.jpeg958F7AD6-6B6F-4519-B403-042CCA4DFFCA.jpegBF0EAD5A-F44A-4BB1-975D-4F691E25D59C.jpeg449A3F8A-F806-4D3D-8AA6-9FC561F8A80E.jpeg
 
Tonight I dealt with a doing something I haven’t been looking forward to on the build. In single Nike smoke mode, I will be flying this in single break head end deployment fashion. The CW Nike nose cone is massive and weights about 5.5 pound itself. It doesn’t have a metal tip with a screw securing it like many other fiberglass nose ones, it has a composite tip that has been epoxied in. This is a problem.

After some deliberation, I settled on what I am going to do to have an anchor in the front of the cone that will provide a secure place to bolt the harness to.

I got two 5/16” inch anchor studs, and a 5/16th bolt. I also cut down some 38mm fiberglass bulkheads a bit to fit farther down the neck on the conical cone. The stack up looked like this:B04C14C3-30DD-4A24-B997-EB8FD98FD82E.jpeg

I sanded the inside of the cone and the epoxy pool that was already there with 80 grit by taping the sandpaper to a long extension. I sanded the best I could, and hoping it was good enough mechanical bond prep. I cleaned it with iso on a Paper towel with a pair of mechanical fingers. I then mixed up 25 grams of aeropoxy, and poured it down in the end of the cone . I then sunk the fastener stack up, after liberally greasing the bolt and plugging the end of the stud threads as well. I am really hoping that this works, because there may not be a way to try again or fix it…so we will see tomorrow morning. Fingers crossed.32E1101C-EF8E-4BF5-B3B3-2E6DD9569163.jpeg
 
Thankfully it seemed that the good mechanical bonding prep worked. Bolt came right out, and took a nylon harness I had lying around and put it in with another washer. Strung the nose cone to Anchor in the ceiling, and hung my wieght from the nose cone carefully. All is well.

I think the only thing I need to do more with this is get a small brass bushing to put between the washer stack so the harness isn’t smashed between the washers.10C5404B-85E7-4212-8F6D-94403ABD5F52.jpeg74EE280C-0375-4108-A678-A407450F845D.jpeg
 
No work done this week as I’ve been on a work trip. However tonight I pulled the trigger on a 75/5120 case, ras set, and motors for first flights both both of these rockets…k1000t for Nike and j415w for tomahawk. Once they both get a shake down flight, I’ll fly them stacked with a booster motor only and do a igniter and separation test before full stages config.
 
Back from the trip, but I got the Rona now. Only thing I really felt up to was run fin sim numbers to verify wether I need to put carbon on the tomahawk fins. Looking at theoretical speeds, I may need to.
 
Woke up early today because my sleep schedule is off due to the Rona(thankfully starting to feel a bit better). Got more of the tomahawk fin can designed in fusion, and designed the fin pockets.

Then got them printed on the prusa, they are about to finish.

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after resting a bit this afternoon, I installed the fin pockets on the tomahawk motor tube. Tomorrow will get some epoxy on the bottom side of the upper and mid centering rings, and if I have some more energy back from this damn rona, maybe I can get it epoxied into the booster.
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I also printed up a bulkhead drill template for the Nike avionics bay, and drilled them up for eyebolts and studs. While putting the hardware together to get a read on how much stud I need to cut off ( needs trimmed close to an inch or so), I realized I really botched the hardware selection when I went to ace two weeks ago. Somehow I only got one 3/8s self locking nut and not enough washers…smh.
Otherwise it looks good and will grab what I need after I am able to leave the house later this week. Tomorrow I’ll cut off the excess threads and be ready for final hardware (self locking nuts on the end) and tighten everything up with loc tight.

Will need to start design on the avionics bay sled soon and build protons.

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Ordered some vaccum bag film as I am out, along with a hose to repair my air compressor so I can vaccum bag some tip to tip carbon on both rockets later this weekend. Also ordered a pro cast kit for igniters for this project as well as in general.
 
Didn’t get as much done today as I wanted, but at least it’s something.

Got epoxy on the tomahawk fwd and mid centering ring on the backsides.

Also had a neighbor grab me what I needed from ace for the avionics bay. I then cut down the rods and then installed hardware on the studs, and loctite on the eyebolts. 4625E31A-FDB5-4044-BD87-B80AB7D6B0AF.jpeg4670B9F0-B393-49FD-AC81-7B80D9474825.jpegF4295497-A9FA-40CD-A1DE-8C3AFA0CF2C0.jpeg25CCD50D-9FE2-4508-82D5-0B1FBCC9272E.jpeg
 
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Tonight I installed the motor tube into the tomahawk. This was quite a complicated step, because of the length of the booster (there was no pouring epoxy down from the top like I would normally do) and small working area with it being 54mm in a 3” tube.

I drilled holes above the upper and lower rings, placed fairly tight to where the rings will seat again the fins. I cut the end off of the tony chaturis meat marinate injector tip, so that only one orifice pointed to the side was left. I then pulled the motor tube back slightly, and injected aeropoxy into the four holes around the circumference of each ring, and then pushed it back up, spun it around to get good spread on the ring. The middle ring was injected through the top of the fin slots. I then temp installed the fins, covering the root with pet to ensure they would not adhere to any stray epoxy. I also cleaned out the fin pockets of any epoxy that strayed into the fin pockets from the bottom ring. I greased the coupler and installed it from the bottom as well to seat the aft ring. I covered the drill holes with tape so the epoxy would back fill the hole mostly, and should only have to do minor hole backfill later. I think I got pretty good coverage. F639DF7E-CD83-4C5E-88E3-1897D6099BA0.jpeg8A4EA156-77A9-4CD0-83D7-07DABAEFE50C.jpeg3174677D-C93D-4AEC-B7AA-F463DCC0F2A5.jpegD53CA2AF-1FAB-4CE6-A8C2-77E61CC88794.jpeg14FB9C50-DA73-43BB-A9D0-A0BBC0DBE21A.jpeg
 
Received composite envisions order this morning, with vacuum bag film and tape. I also placed the paint order for these rockets from airbrush paint direct.
 
Rocking and rolling on the build, good stuff. :)

Thanks...I might be delusional but I am attempting to get things wrapped before it gets too cold and It becomes hard to paint....we shall see. If it does get too cold then I guess they will have to fly naked and get painted in spring.
 
I love aeropoxy, but it is not the best when trying to get alot of actions done in a given day. However I hit the timing about as good as I could this morning when I glued fin 2 in, because about 2200 tonight I got the last fin in the tomahawk sustainer fin pocket. I also drilled and glued in the fwd rail button stud. Good day.

In a late Amazon delivery, I received some silicone straws of three different diameters. This is an accompanying accessory for the procast igniter kit I ordered from magnelight. Will make some 12v standard igniters for ground use and augment ematches for air starting the sustainer when I start doing that for this build.

Last recieved was some Elmer’s glue all max, needed for the 75mm k1000T for Nikes first flight in late oct/early nov.
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Forgot to post yesterday, but started fillets. Turned out well, there was a scare I almost waited too long to pull tape and smooth out and shape the fillets.


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Thats the next step for the Nike....Will have a Quantum, Proton, and tracker in it. Thinking tomorrow I will get into fusion and start the avionics bay design.
 
It's a fine balance for avionics space, motor case space, and recovery stuff. Careful with those eggtimer wifi switches, they are power-hungry beasts.

Standing theory is my wifi switch killed my lipos and the avionics died and the pyro charges never fired - this was how my Nike ended up on it's second flight.
 

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Ouch. I have been using these egg products with 780 mah batteries for awhile now, feel comfortable with them, especially with redundancy. Thanks for things to consider though, will keep in mind.
 
3rd set of fillets on Tomahawk this morning image.jpg

Also received paint order for this build, and procast kit along with cat 5 cable to make 12v igniters. I will dip ematches in procast for Sustainer ignition for this project.5693F58C-9D3C-4C45-A4A5-8A2746896871.jpeg5E9B67DE-58F3-48F5-986A-458BD72AC567.jpeg
 
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Tonight I got the last fillets down on tomahawk. I then started cutting templates for the carbon fiber tip to tip. Will vaccum bag tomorrow. 9C4BBD0C-F52E-4027-9FBF-A7F923BB56DE.jpegBB0F9860-9536-408C-A0D7-3F69464EA9D3.jpeg1877A5E5-7DEC-4C3A-B4D2-18147D00761B.jpeg
 
Today was focused on doing carbon tip to tip reinforcement on the Nike booster fins. I decided to do this because of doing some finsim analysis on the fins. There was some indecisiveness on what finsim results gave me, and because being right up on the edge what it said would give divergence and flutter. I don’t want to have to rebuild and have a mishap later on down the road when I push the rockets to higher speeds, so just committed to doing it on both rockets.

I cut all the skins with different size templates for the different layers, and peel ply and breather.

Mixed up aeropoxy laminating epoxy, and applied the two layers and all other materials. This is my first time using proper vac bag setup, as opposed to my previous experiences laminating just fins with a food saver on a few other rockets I’ve built. I learned a lot tonight, and think that for the sustainer I will try to bag the whole tube and seal the bag instead of sealing the bag against the tube like I did tonight. It’s def not going to be pretty, there are some wrinkles in the breather and bag. It’s getting painted over, so I think it will be functional at least so not the worst thing…nothing some sanding won’t fix. D6B37BF4-4D1E-4B7C-BBB3-A8AFC6D078B1.jpeg
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