Level 2 project: "Long Tom" LOC Cruiser -> stretched Tomahawk CM

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Updated Fin progress in Post 3

Busy week at work. I got the main fins tacked on and some preliminary nose and rail button mount work in.

Nose teaser:
20180511_185537.jpg
 
Then I found a big 5.5" elliptical nosecone in Madcow's Rocketry Warehouse acquisition stash.

That nose cone is sweet. I was in Madcow a few days ago and saw a 4" elliptical sitting on top of a tube. I think I am going to pick one up next time I'm in the area and just set it aside.
 
That nose cone is sweet. I was in Madcow a few days ago and saw a 4" elliptical sitting on top of a tube. I think I am going to pick one up next time I'm in the area and just set it aside.

Right? It's not like ALL the tubes have to be pointy.

Plus, less chance of poking your eye out with this one
 
Update

My schedule's 3 day weekend came up so I made some good (if unorganized) progress on Long Tom.

Booster Business! I'd say it's ~70% done at this point.

Nose! 80% done, just need to figure out shear pin mechanisms

Bonus Tailcone aesthetics! Had some leftover rocketpoxy that hadn't cured yet.


I've sent my T3 off to Missileworks for repair, so when it gets back I may start working on my av-bay.

Stay tuned!
 
Took a progress shot. There are much fewer loose parts lying around compared to the picture in the first post.


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This is a great build. Congratulations also on doing something different from the 3FNC norm, and good luck with the cert. In my experience RL is definitely the propellant for a L2 cert :)
 
This is a great build. Congratulations also on doing something different from the 3FNC norm, and good luck with the cert. In my experience RL is definitely the propellant for a L2 cert :)

Thanks Tim! 3 fin jobs are certainly easy, but I just find them so,........boring. Living in the eastern US leads me away from high performance airframe's too (the trees are big fans of out of sight flights east of the Mississippi)

I only have two simple 3fnc's currently: the Partizon from my Pro Series II collection, and a mammoth I was gifted that I use for tracker testing.

I may have to redo my L1 flight at Naram just so I can get a better picture/video
 
I'm packing for a trip out to Iceland with my best friend from college, so not much physical has been done on Long Tom in the last couple days beyond gluing in more coupler segments to the payload bay and installing the stiffy coupler in the ebay. All the couplers have been fixed in with titebond II, with some superglue on the edges to seal things.
20180521_213342.jpg

In preparation for time away from the physical rocket, I pulled the relevant external dimensions for my normal virtual flow models. Colors For Dollars will abound!

solid.PNG
 
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Last update before I depart:

I got the wings tacked on!
Discovered this little clip on flashlight I got from a job interview a couple years ago. It is fantastic for clipping onto tubes and lighting glue areas.
20180524_075103.jpg

I also weighed the major assemblies:
-Nose, payload, Ebay (undrilled, w/o shear strips, rigging, or electronics): 4# 8.7oz
-Booster (w/o fillets, camera, rail buttons, forward centering ring, final stiffener, or rigging): 5# 8oz
 
Got back from Iceland a week ago and have finished unpacking, catching up on work, and straightening the apartment.

Small progress was made in spare moments:
-1515 rail buttons installed
-Final coupler segment loaded in Booster ahead of forward wing centering ring (E-bay fit checked)
-Wings filleted with TBII -> TBQ&T
-Nose shear pins drilled and tapped
-Ebay vent holes and rivet holes marked
-Alignment key cutouts marked

To do:
-Drill vent and rivet holes
-Mount electronics on sled
-Mount bulkhead connections and charge wells
-Fillet main fins (need to figure out the rocketpoxy timeframe for laying fillets on a curved surface....)
-Weigh and balance with rigging
-Fabricate noseweight pucks (lead/epoxy)
-Ground test
-Paint
 
Took a picture to send to someone and figured I'd put it here too.

11 lbs currently

image.jpg
 
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-Fillet main fins (need to figure out the rocketpoxy timeframe for laying fillets on a curved surface....)

I let my mixed Rocketpoxy sit for 23-25 minutes before it is applied. It still flows a little bit though. Maybe a minute or two more sitting for a curved fillet would help, before contouring with and alcohol dipped pulling tool of your choice.
 
I let my mixed Rocketpoxy sit for 23-25 minutes before it is applied. It still flows a little bit though. Maybe a minute or two more sitting for a curved fillet would help, before contouring with and alcohol dipped pulling tool of your choice.

Great, that's a starting point. I've heard "let sit ~20 mins" before, but I'm sure I'll need to tweak and experiment a little.
The nosecone tip I cut off has been the perfect fillet tool so far.

Should probably start on the rail side and see how those come out.
 
Got my electronics arranged, just waiting on my repaired T3 to arrive in the mail.

Ebay

Got all my shock cords and parachutes bundled ready for ground testing

Recovery
 
So, I can't edit my posts anymore. Oh well, guess it's back to the old fashioned way. Is editing a supporter function only now?

Current state of the rocket! (Mammoth for scale)


I installed brass shear strips in the payload tube. No worn holes in cardboard for this rocket! After pealing out the sockets, I used basic BS 30min epoxy, covered them with masking tape, and used the nose shoulder to press them into the proper contour.


I've started making filler strips for the booster's factory fin slots. Turns out this old mailing tube I had is almost an exact match for Loc tubing thickness. They seat in nicely but a couple places had to be restrained for the wood glue to set.


Facebook kindly reminded me that a year ago yesterday, I made my first eby for Vertigo II (electronic Ventris). I've come a long way since stuffing a stratologger and a lipo into a PSII transition. Fitting that a year later I'm polishing up the ebay for my L2.


On the board front is an RRC3 (primary), Stratologger CF (backup), and T3 gps. All electronics have been flight tested and are functional. The tracker's wire is run lateral so it doesn't mesh with the 2 threaded rids running along the board. 3 stiff flip switches are used for activation and they are my new favorite thing (when I have room for them).


The batteries are butted up against the rod guides for bracing against thrust acceleration (the aft end of the sled is up in the pictures). A 9V for the RRC3, 2S 800mAh lipo for stratologger, and a 1S 950mAh for the T3 (the tracker will Not die!). They hav velcro on their backs, and when the bay is assembled, the batteries will be strapped in over top.

A note on keying, In order to reduce confusion when wiring, I've taken steps to make sure everything goes to the right place. Drogue side is wired directly to the aft terminal blocks. Red for primary Black for Backup (alliteration!). The fore cap is separate and uses JST connectors. Male pigtail on the Main (primary) altimeter (RRC3), female on the backup stratologger. Main charges cannot be wired to drogue outputs and vice versa. Prime and Backup for main physically cannot be mixed up. Drogue side will be wired up physically at a calmer place free from distractions.

Laundry day! 35' 5/8" tubular nylon harnesses from Loc. 18" drogue came stock, it should work. 60" ripstop stock main.....I need to investigate upsizing that since I'm landing on Colorado hardness. The rocket has gained some weight and still needs paint. No cracked fins desired. 18x18 nomex work fine to protect the innards, and the cord ends get my 'custom' ductape protectors.


Also, video! Deployment testing!

Ground test went perfectly. 1.48 gr for drogue, 2.25 for main breaking all pins. I'll retest tomorrow to verify and be all set!

Last steps of build are aft fin fillets. That's the part I've been dreading.....
 

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Images that disappeared somehow....

scale shot
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shear strips
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slot filling
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Anniversary ebay
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Ebay sled front and back
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Laundr
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I've done the boat tail fillets w/rocketpoxy. Won't lie and say it didn't cause me lost sleep. But in the end it wasn't bad at all. Just mix it and let it sit 'till it "feels" right and it'll stay where you put it. Bubbles were actually the biggest problem in the end..
 
Does angling the tube so each end is less sloped help any, or is it better to just let it sit ~22mins and pour with the tube flat?
 
I did shim one end of my stand, definitely didn't hurt. Timing and weather/temp is the key with Rocketpoxy. It's more of an art than anything else.
 
If you really want it to set quick just pre-heat it. It'll run like water for maybe a minute and then it's all over. Ask me how I know....
 
I was expecting cheerful fillet success pics by now...We all know you can do it...
 
I have to psych myself up to start the process. Sunday/Monday were preparing for ground testing, and yesterday I was at a birthday dinner/trivia night combo.

I have time before I've got to drive to NARAM, but thanks for the anticipation lol
 
First attempt at rocketpoxy fillets on this boattail came out....not bad honestly. I have no complaints with the result considering i:
-Overestimated the mix quantity
-let it sit a taaaad too long
-spooned in too much to the corner

It really sank into place well, evened out nicely, and responded cooperatively to the initial tongue depresor and then the alcoholic nose tip. Tape peeled up fine, and an alcoholic gloved finger cleaned up any stray bits and did the end molding.

I should have started this a week ago, it really wasn't as bad as I feared.20180628_234837.jpg 20180628_234749.jpg
 

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Told Ya. Looks great. A couple different sized/shaped files and a bit of spot putty here and there...High build primer is also your friend...
 
It also never occurred to me to use my nose for forming fillets. Did it leave a mark?
 
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