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Zippers, Zips, Twister Stix, Speed Balls, Lil-kidz?


yvanblo

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I don't know how your 'really hot willow' performs. I know that the formula supplied performs well-enough that it won a small-effects competition. If yours doesn't perform to that level, then you can 1) mill it longer, 2) adjust the nozzle size --- <shrug>

 

Your estimation of 'how it works' is in concert with my opinion. If your powder just isn't fast enough, you can reduce the nozzle size some to improve its rate of burn.

 

But consider that there's a perc-based FAST color comp amounting to about 1/3 of that whole powder column. That may-well be why I had to slow the BP comp!

 

Lloyd

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  • 1 year later...

Ok, I know this is an old post, but it's my post... so... ha. Anyway, I went the extra mile this year and cut a twister stix in half down the middle. I took exact measurements, and drew it up in sketchup. I then made tooling to match. With my alder charcoal black powder green mix (just milled, not even granulated) as the second stage, and some slower black powder as the first stage, I got a great launch on my first test. Have a look:

 

I'm quite happy with the result! It takes about 5 minutes or so to make one, so not too bad.

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That got up and went lol

Yes sir. That's what I love about these lil guys. Such a fun sound too.

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I'm not entirely sure I understand how these are made. Are we talking "stinger"-style rockets? From a couple of the videos I found it looked like they were lying down...

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I'm not entirely sure I understand how these are made. Are we talking "stinger"-style rockets? From a couple of the videos I found it looked like they were lying down...

Yes, this is a stinger type spin stabilized rocket. But it's tiny; 34mm x 14mm. Smaller than your pinky finger.

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I see. That's pretty nice performance, even launched from a nail my stingers were erratic at best.

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Fulmen, Thanks for the compliment!! I've been experimenting for many years to get my design working. It took a great deal more effort and precise measuring than I thought it would. Also, I've only ever launched stingers from nails, and I've never had a problem with them being erratic... straight up every time. Is it possible that your design is not optimized? Maybe the spin hole is in the wrong spot? Give us some more details on your design, and I'll bet we can help you get it working... certainly many folks on here are pro's when it comes to stingers.

 

I've made several spin stabilized rocket designs, buzz bombs, lady bugs, scrabs (bigger lady bugs), stingers, mini stingers, zingers (this post), and several hybrid ones that I made up. Tangential spin holes in the right spot are critical. Nail launch designs have the most consistent results in terms of vertical launch. Though I made one the other day with 3 randomly place holes at random heights and it worked just fine... 1/2" ID x 3/4" height, first hole at bottom of powder column, second hole around 1/4" up, third somewhere near the top. Flew just fine... it was a happy accident that I made from a scrap tube that I used to test where my holes were being drilled with my jig.

 

I just hope that the rest of the zingers I make work as well as this one... I'm trying a few things that may help both the pitch of the zing (higher is better, in my opinion), including a slightly longer lift comp powder column, and reinforced spin nozzle.

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It's been so long I have to start from scratch. But they were 16mm ID, single spin hole at the bottom placed tangentially with the inner wall.

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  • 3 weeks later...

I meant to post this screenshot here the other day, but must have placed in a different topic that was also discussing these little zingers. Here is my zinger diagram. The tube ID is 10.4mm

Zinger diagram

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By the way, if you use the dimensions in the diagram I posted, I made a slight change that greatly increases the "zing volume". Instead of a 3mm core, make it 2mm. So loud. I can't imagine how many RPM these little guys are pulling! I'm tempted to also make the spin nozzle smaller, but I may be close to the pressure limit of what the casing can handle.... I'll give it a spin... if it explodes, it's still fun.

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@yvanblo: Thank you. A few tips for the future though: The 3/4-section is useful for visualizing the part, not so much for measurements. A 1/2 or better yet a plain 2D drawing is usually easier to read.

Also, there is no need for 0,01mm resolution. I would probably round it off to the nearest 0,5mm, some fine tuning is inevitable.

 

BTW, it might be a good idea to include the comp in the drawing.

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@Fulmen That makes sense. Though the comp is in that drawing... unless you mean the actual composition that I mixed, which is simply 75:15:10 alder charcoal black powder.

zinger cross section with greater detail

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Perfect. Except for one last thing, a good title. That way the image alone will be enough to figure out what it is and how to make it.

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The result of a smaller thrust nozzle is more 'zing volume'!!:

Edited by yvanblo
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  • 1 month later...
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Nice work, Bigmark! Glad to see someone else is making these. What size are those?

these are 5/16 id 1/2" od 1 3/4" long. Got the tubes from Woodysrocks.com just cut them down to size.
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  • 2 years later...

dynomike1, thanks, if you find a comp, let me know what it is, I'd love to try one.

 

Lloyd, thanks for the reply. It sounds like you have experience with these. I flew one yesterday, and it was lazy. Although, admittedly, I had some trouble with the nozzle and plug clay. I'm going to replace my nozzle clay and see what happens.

 

The last time these worked for me (a few years ago), I was using normal 75,15,10 BP. But the noise they made was pretty lazy as well. This year I took careful measurements of a twister stix, and made some tooling and jigs. I just completed the tools last night, so we'll see what happens when I get one made with new clay.

 

The factory ones scream, and I would love to replicate that sound. In your attempts, have you gotten that awesome screaming zing out of them?

How to put hole in the tube cane you explain

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