New scratch build, "Thump In My Down"

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qquake2k

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Got the coupler and baffle plate epoxied in.

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qquake2k

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I forgot to mark the position of the forward rail button before I epoxied the baffle plate in place. So I guessed, and lucked out.

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qquake2k

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The fin tabs ended up a little too long. So I pinned them back together, and sanded off about 1/16". That's all it took.

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qquake2k

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Using my handy fin guide, I got all 6 fins epoxied on. This is actually my third rocket with 6 fins, but the first with all 6 fins the same size, shape, and orientation.

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qquake2k

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I'm liking it! The nose cone is repurposed from a broken rocket.

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qquake2k

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Got the aft rail button installed, and the external fillets applied.

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qquake2k

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I've done this before to flat bottomed rockets. I added a slice of body tube to double up the aft end. Hopefully, this will limit landing damage.

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T-Rex

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Coming along nicely... Pretty soon you're going to have to get an out building of some sort (or rent a storage unit) for all your rockets!
 

Woody's Workshop

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That's a neat way of beefing up the butt end of things Jim.
I've been filling area between the engine tube and body tube with glue.
But I don't deal with engine retainers....yet.
This would save a heck of a lot of glue!
Thanks for sharing this!
Love your build threads.
 

TangoJuliet

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I like the look of this one too!

I also like your Fin Jig. Are there plans available for making one in a smaller scale for LPR/MPR rockets?
 

qquake2k

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TangoJuliet

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Excellent! Thank you. Now I just need to locate a friend with a table saw who can cut the 45* edge for me on a couple of 1x4's.
 

qquake2k

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Excellent! Thank you. Now I just need to locate a friend with a table saw who can cut the 45* edge for me on a couple of 1x4's.
If you have a router table, you could use a 45 degree chamfer bit.
 

AfterBurners

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Got the aft rail button installed, and the external fillets applied.
I have a question? How come when you mount your rail buttons they aren't centered on the line you drawn? I'm just curious and figured there's a reason behind it and probably a good one. Is it easier to get them lined up? They look really nice.
 

qquake2k

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I have a question? How come when you mount your rail buttons they aren't centered on the line you drawn? I'm just curious and figured there's a reason behind it and probably a good one. Is it easier to get them lined up? They look really nice.
It's because the fins are mounted to the right of the lines, instead of centered on the lines. The fins are 1/4" thick, so to keep the rail buttons centered, they need to be placed 1/8" to the right.
 

AfterBurners

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There is a backstory to the name. When I was a kid, my mom used to tell me a story about when she and my uncle were kids. My grandmother accused Uncle Raymond of farting. He said to her, "I didn't feel a thump in my down, mama!" Well, it sounds like a good name for a rocket to me!
Thump will be 4" diameter, 64" long, have 6 fins, a 38mm motor mount, and be a zipperless design.
Never trust a fart! :lol::lol::lol::lol::lol::rofl::rofl::rofl:
 

qquake2k

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Plasma...another word for blood if I'm not mistaken.
Bloody Fart...Might not be so good...
Of course...Vulcan blood is green...
Bloody Fart? Not so much. LOL

Vulcan Fart? Not bad. In fact, you could do a whole series of "fart" rockets. Plasma Fart, Vulcan Fart, Ion Fart, Laser Fart, etc.
 
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qquake2k

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Got the retention clips done. I used 1/8" x 1/2" aluminum bar.

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TangoJuliet

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Nice, but that lower bend looks like a weak point and susceptible to breakage.
 

qquake2k

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Nice, but that lower bend looks like a weak point and susceptible to breakage.
I have been making them the same way and from the same material for years. I haven't had one fail yet.
 
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