As yet unnamed scratch build - now Running With Scissors

I started a discussion thread about my concerns over a long conical fiberglass nose cone with a pound of nose weight, and the damage it could cause if it came in ballistic. I haven't made my final decisions yet, but I decided to start the build thread. My designs always change and evolve during the builds anyway.

Beyond the nose cone, I still haven't decided on the length, fin thickness, or name. There were some concerns raised in the discussion thread about fin flutter, so I'm considering using 3/8" plywood. As for the length, I was originally planning on an 8-1/2" long 4" body tube, but I may increase it slightly to 10", just for the extra interior space.

For the name, I first thought of the "Runt", then "DooDad", then "Obloid" (if I go with the ogive nose cone). In the discussion thread, CCotner suggested "Cause For Concern", and cjp suggested "Mako Shark". Decisions decisions!

View attachment DooDad_cone1c.ork

View attachment DooDad_cone1c_long.ork

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View attachment DooDad_cone1d_long.ork

I played around in Photoshop, just to get an idea of how the short and long versions would look.

Lots of sharp and pointy bits there. Two names that come to mind are "Don't Run With Scissors" and "Killer Bee Sting".

Regardless of the decisions I need to make, I'll need centering rings. I already had one that I didn't use on a previous build, but I needed to make another. They're both made from 1/4" birch plywood. As usual, I cut it with a 4-1/4" hole saw, and sized it on the lathe. I cut the inside hole with a 2-1/4" hole saw, for the 54mm motor tube. I also epoxied on blocks for the tee nuts, and rail button.

My goodness man ,do you ever rest ?????

That`s kind of a neat looking rocket,should be cool !

And they banned LAWN DARTS :y:

Take care Jim



Paul T

For the tail cone, I'm using a LOC 3"-4" transition. I cut the loops off so the ends would be flat, then cut off both shoulders. I left 1" of the 4" shoulder that will go into the body tube.

Using the Loc transition is absolutely brilliant Jim ,that`s an idea I shall have to use !

Thanks for posting this :clap:


Cheers


Paul T

sodmeister said:

And they banned LAWN DARTS :y:

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They were called 'Jarts'. That name would go well with your design Jim.

bradycros said:

They were called 'Jarts'. That name would go well with your design Jim.

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It`s always my goal to learn at least one new thing a day.....

...JARTS....who knew ,although I could pull the old "up here in Canada ,we call them........) but I won`t this time LOL



Paul T

sodmeister said:

It`s always my goal to learn at least one new thing a day.....

...JARTS....who knew ,although I could pull the old "up here in Canada ,we call them........) but I won`t this time LOL



Paul T

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LMAO! :rofl:


TA

Funny, I was playing jarts yesterday with my friend...

sodmeister said:

My goodness man ,do you ever rest ?????

That`s kind of a neat looking rocket,should be cool !

And they banned LAWN DARTS :y:

Take care Jim

Paul T

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Actually, I do rest, Paul. That's why X-Plane and Bluto aren't finished yet!

sodmeister said:

Using the Loc transition is absolutely brilliant Jim ,that`s an idea I shall have to use !

Thanks for posting this :clap:

Cheers

Paul T

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Yes it is brilliant, but it's not my idea. I saw it here on TRF. I've seen nose cones used as tail cones, too.

scsager said:

Lots of sharp and pointy bits there. Two names that come to mind are "Don't Run With Scissors" and "Killer Bee Sting".

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bradycros said:

They were called 'Jarts'. That name would go well with your design Jim.

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You guys are giving me way too many great name ideas!

I sanded the ends of the transition/tail cone with the disc sander. By the way, the short length of black body tube is to hold the small end square to the sander.

More mundane tasks that are common to most of my builds. I installed and epoxied the tee-nuts in place. I also epoxied the nuts on the u-bolt.

I sanded the rail button block on the centering ring. I also had to sand a corner of the u-bolt backing plate. And just to be sure, I put some epoxy on the other u-bolt nuts.

And the first dry fit of the tail cone. Looks pretty good. This is an 8-1/2" length of body tube. I still haven't decided on 8-1/2" or 10".

qquake2k said:

And the first dry fit of the tail cone. Looks pretty good. This is an 8-1/2" length of body tube. I still haven't decided on 8-1/2" or 10".

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That looks perfect Jim. I have used nosecones before and made my own from BB plywood,but I love the look of the transition better in every respect.

Cheers

Paul t

It kinda looks like a battle mace. I like the lines of the ogive cone more than the conical.

Paint it green and black and call it "Poison Dart"

Paint it yellow and black and call it "Stinger"

Paint it red and black and call it "Deadly Dart"

rocketgeek101 said:

Paint it green and black and call it "Poison Dart"

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Second! I even found you a mascot.

Well, I've made some decisions. I'm going with the 5:1 ogive nose cone, longer body tube, and 3/8" fins. I made the fins slightly larger, and I think they look better. I'm also leaning towards black and yellow. I've decided to use a plastic nose cone and phenolic body tube from Giant Leap, and ordered them this morning.

View attachment DooDad_cone1c_long_v2.ork

I noticed this morning that I had cut the shoulder on the tail cone slightly off. I was going to try trimming it with the bandsaw, but decided to use the disc sander instead. It worked well.

I had to print yet another fin template, because the OD of the phenolic tube is 4.024", so the fin tabs need to be a tiny bit longer. I'm using 3/8" birch plywood from Michael's. I pinned the blanks with 1/4" dowels, as usual, to cut and match sand the fins at the same time.

I cut them freehand on the bandsaw, except for the tabs. I used the fence on the saw to get the tabs as straight as possible.

I sanded the straight leading edge with the stationary 6" belt sander, and the inside trailing edges with the 1" sander. You know, I bought that little sander on a whim because it was on sale. I never realized at the time just how much I'd use it.

The fins turned out pretty good, overall. One ended up with some chips, but I'll fix those with Bondo spot putty. I thought about slightly rounding the tips, but was afraid I wouldn't like the look. I know they'll end up getting damaged, but it'll look good for that first launch!

qquake2k said:

but it'll look good for that first launch!

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'Tis all that matters :wink:

Cl(VII) said:

Second! I even found you a mascot.

View attachment 128336

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How about "Dart Frog"? Looks cool Jim.

I have one of those little sanders also Jim ,bought it on sale a couple of years ago ,I use it all the time instead of my big floor model.


Paul t