Lakeroadster's "Hammerhead Shark"

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.... There is a very EASY solution when you don't need much diameter. ..... masking tape...

Thanks for the suggestion.

My concern. I have some old rolls of masking tape and their appearance make me nervous about using this technique. Not that I would use the old tape, the old rolls of masking tape are no longer smooth, they are wrinkled up. Long term, would this happen to the body tube? Also masking tape, by design, has a coating to give it the ability not to absorb paint, which makes me wonder just how well it will absorb CA, and how well it will adhere to the cardboard body tube.

So as an alternative... how about using regular printer paper cut into strips and then use white glue, basically winding a 1/4" wide strip and making a DIY paper fiber centering ring? Similar to the method that folks use to make their own body tubes. Then everything would be paper based and thus wood fibers attaching to wood fibers.
 
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So as an alternative... how about using regular printer paper cut into strips and then use white glue, basically winding a 1/4" wide strip and making a DIY paper fiber centering ring? Similar to the method that folks use to make their own body tubes. Then everything would be paper based and thus wood fibers attaching to wood fibers.

That's a good idea, I think that there was an Apogee newsletter using this method for a 29mm centering ring in a BT-55 body tube.
 
It should be called Mjölnir. :D
For those (like me) without Baltic heritage


Drawing of a Viking Age gilded silver Mjölnir pendant (length 4.6 cm) found at Bredsätra in Öland, Sweden, now kept in the Swedish Museum of National Antiquities
In Norse mythology, Mjölnir (/ˈmjɔːlnɪər/;[1] Old Norse: Mjǫllnir, IPA: [ˈmjɔlːnir])[2] is the hammer of Thor, the Norse god associated with thunder. Mjölnir is depicted in Norse mythology as one of the most fearsome and powerful weapons in existence, capable of leveling mountains.[3][4][5] In its account of Norse mythology, the Prose Edda relates how the hammer's characteristically short handle was due to a mistake during its manufacture.

From

https://en.m.wikipedia.org/wiki/Mjölnir
 
Is that Scandinavian Doctor Who fans?

I was pretty sure Scandihoovian predated the Doctor, but had to look it up to be sure. It's from the late 1800's and was originally derogatory. It's now largely used by Scandinavians (actually, more likely multi-generational Scandinavian-Americans) in a good-natured and self-referential way.
 
Motor Mount

Finished up the motor mount today. Turned down the diy centering rings on the wood lathe, and drilled the hole for the kevlar recovery strap.

Let the obnoxiously large glue filletting begin!

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Started gluing the fins to the body. This is the first rocket that I have used through the body tube fin tabs to locate all the fins... they sure do make installing the fins easier.

I had some help from some Native American artifacts in holding everything in place. Getting by with a little help from some old friends.

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I knew the Hammerhead needed quite a bit of weight in the nose. I went back and fine tuned the Open Rocket simulation to reflect the as built fuselage and nose cone and the nose cone weight increased.

I bored out the nose cone C/L to 11/16" i.d. x 3-5/8" deep, and then cross drilled the head at the "eyeballs" using a 5/16" dia. drill bit.

I'll use lead in the nose cone and some pan head screws for the eyeballs... "A little Led for the head"

With the extra weight I'm now planning to use (2) 12" chutes for the head, (2) 12" chutes for the body and a 29 mm F20-W4 motor for the 1st launch... apogee at 705 ft.

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I always like it when one structural part can serve two completely different purposes.

Your shark eyes actually are cosmetically pretty cool just by themselves (so nice and shiny I am thinking you just reattach them after painting the rest of the rocket, let ‘em shine!) as well as contributing to the forward mass/CG shift.
 
I always like it when one structural part can serve two completely different purposes.

Your shark eyes actually are cosmetically pretty cool just by themselves (so nice and shiny I am thinking you just reattach them after painting the rest of the rocket, let ‘em shine!) as well as contributing to the forward mass/CG shift.

Thanks. That's the ole form follows function thingy.

I was racking my brain trying to figure out how to add weight near the nose... and then it came to me.. in my mind's EYE. o_O

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1st coat of Rustoleum Sandable Filler Primer.

I sanded the primer today. I need to add some EWF on the nose cone, but decided to wait a few days just to make sure the primer is cured.

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