MAC Performance 3FNC on a Loki K960

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3stoogesrocketry

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Well the time has come . It has been to long since I have done a "crazy" build . That has to change . I present for your veiwing pleasure , the new MAC 3FNC . This rocket has been upgraded to a 54mm motor mount , and will be flying on a Loki K960 . Sims put it around mach 1.8 and north of 10k . The rocket has a total length of right around 33 inches . It will be a full DD recovery . Twin altimeters . Flame length to rocket at least 3:1 . Much more to come .

Eric

Looks like my new phone is being special , I can build a mach 2 rocket but cannot upload a picture .

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Will be watch! Be interesting use space stuff 2 harnesses, chute and AV bay in that thing! Considering chute release?
 
I wanted to do this when MAC first announced the 3FNC. I'll be watching...
 
I think this will be reminiscent of that Shadow Composites bird you did at an early NERRF on the original Loki J1001B. 5-5-3-2-1-Where the Fark did it go?!?

At least I think that was you.
 
Will be interested to see this one! I tend to struggle finding creative electronic and recovery configs, this should be educational for me!
 
Mach 1.8 sounds like it would be pushing Mac tubing real hard.

I've never had the pleasure of building a MAC product- I'm guessing it's not fiberglass? Just assumed it was.

Looked it up- canvas phenolic...interesting! Does it carry some of the limitations I've read about phenolic tubes in general, or is there a specific concern with high speed flight?
 
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Yes Al that was me lol . As far as the strength of the 4 inch tube , I am exteemly impressed with the strength of the tube . The fins are ( I upgraded to 3/16 over the stock 1/8 ) incredibly stiff , and the bevels are beautiful .
 
These pictures are of the fins , obviously . My camera does not capture the true quality of these fins . I will though be altering the fins a bit to not only be stronger , but will ensure the fins will NEVER come out of the rocket. Also , there will be ZERO reinforcment to the fins / body tube . My next post will show the modification of my hard balsa tail cone into a integraded motor retainer .

Eric

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Here is a basic parts layout of what is included in the kit. The main body tube I had extended to 12 inches it is normally 8.5 inches. The phenolic 54 millimeter tube will not be used in this build. Up next is a 3 inch phenolic body tube which is used as a nose cone coupler and parachute tube and is 10 inches long . The 5 to 1 Pinnacle nose cone has a 1 inch shoulder. The bulkhead with the U-Bolt and 12 inch Kevlar shock cord has a stepped shoulder on it so it will engage in the three-inch body tube but not pull through. There are two four inch to 54 millimeter centering Rings quarter inch thick 7 ply birch. There is a centering ring with a 54mm inside diameter , step milled to engage in the nosecone , 3/8 tbick 9 ply bircb. The next centering ring is a 4 inch to 54 millimeter but has a CNC milled circle in it to engage a piece of 3 inch body tube and it's very snug fit. There is a 1 inch long piece of 3 inch phenolic body tube which glues into this ring slot. There is then a 3 inch long coupler tube that glues into the 1 inch long BT and engages into the three-inch body tube inside the nose cone . It is a strong design. I will be modifying it though however to fit my needs. The last ring engages on the outside of the three inch tube and centers the tube inside the nose cone. There are three very nice fins that will be receiving a slight modification to aid in building , and should be done to future fins for this type of velocity , and hopefully to keep this bird in one piece. I will be adding many pieces as well as taking away many pieces to this build. Stay tuned for further details.

Eric

PS. This will be a culmination of 20-plus years of flying HPR and showing some of the tips and tricks I have learned along the way. This will not be a debate thread or a "you should have done it this way thread" .

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I have one of these on my birthday wish list. It would be my third MAC kit. I love them.
 
[/QUOTE] This will not be a debate thread or a "you should have done it this way thread" .[/QUOTE]



Amen brother!

I did a big motor[54mm 6-grain] in small rocket [1/8in fins] years ago...and caught the "wraith". Ignored it & went on to fly successfully for many, many flights......No nose weight...LOL

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I commend you on your effort & best of luck with this project!
It's always fun pushing the envelope.[especially when it works]
 
Any updates? I'd love to hear how this one turned out.
 
This will be a very brief writup for now , I will add more details later when I have a few more minutes of time .20160923_174240.jpg
Here is the basic parts layout that I will be using for this build .
20160924_084230.jpg The nose cone uses a 3 inch stuffer tube for not only recovery room , but also there is a 3 inch long 3 inch coupler that is used for additional nose support under load . I will be retaining this tube for my drouge area . 20160924_084241.jpg20160924_084412.jpg the last two pics show the very nice stepped ring that is supplied with the kit. I simply potted a 2 foot length of 1/4 inch TK with a beautifuly sewn and heat shrinked end .
 
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