Fin Assemblies

[L0k1]

Hey guys. New to the group and wanted to share something I've been working on.

 

I ran low on dowels and really hate needing a tube to launch. Which got me thinking. Model rockets don't use sticks, so why not try to mount some fins on my engines?

 

Let me just say, I'm not a designer but I do ok.

 

So I set to work on Fusion360 and began some designs and sent them to my heavily modded ender3. The first few were....lacking to say the least. Had one that did a backflip and went horizontal, which looked damn cool but not what I was going for.

 

Some experimentation and reading yielded the knowledge regarding size and position.

 

I've currently created working cohete and 1lb fin assemblies. The rockets go up, albeit in an unpredictable direction. I'm still experimenting and testing with upswept fins, slightly longer and taller as well. I'll post as they improve. They may take a bit of work to slide them in, or you can heat the assembly with a dryer and load your engine, after pressing of course. The assemblies also elongate the whistling section which 4 me has increased the volume to a high degree. I've also created notches on the bottom to allow the fuse to stick out without making the rocket topple over or lean to the side.

 

Basically, these can get your rockets into the air without a stick. no balancing needed with small payloads. Just slide the engine down until it won't move anymore and glue them in.

 

I'd love to hear what all you think about them or any suggestions you may have. I just hope to contribute something meaningful and something that everyone wants to use. I'd be willing to print and sell them as well but I'll share the files with you to use. If you get rich off my design, I expect royalties (kidding, not kidding).

 

If you like it let me know why.

 

If you think it blows dolphins on Tuesdays for nickels, let me know why.

 

L0k1

 

Also included a couple pics Prometheus Assembly.

 

*Well, cant upload STL so I just gotta link you to Thingiverse

Coldstrike Assembly 1.75 inch - https://www.thingiverse.com/thing:6081920

Prometheus Assembly 1.5 inch - https://www.thingiverse.com/thing:6081929

Mjulnir - https://www.thingiverse.com/thing:6081926

[Bamboozler]

Maybe more fin surface area to allow the rocket to fly straight?

 

Love playing with Solidworks to create different pyro models. Good job on the creativeness.

 

My contribution to your thread, print one out and give it a go.

 

https://youtube.com/shorts/xAK7dOjxUgg

 

Model download link for 1lb tubes (fin, fuse disc, payload, rocket tip) (copy/paste into browser): http://www.pcbwerks.com/3D/1lb_Payload.zip

[cmjlab]

That one flew pretty nicely too. Very neat.

[L0k1]

Maybe more fin surface area to allow the rocket to fly straight?

 

Love playing with Solidworks to create different pyro models. Good job on the creativeness.

 

My contribution to your thread, print one out and give it a go.

 

https://youtube.com/shorts/xAK7dOjxUgg

 

Model download link for 1lb tubes (fin, fuse disc, payload, rocket tip) (copy/paste into browser): http://www.pcbwerks.com/3D/1lb_Payload.zip

I love the idea. I'm so impatient though. I always try to make my prints go as quickly as possible. Pyro has taught me some modicum ov patience but in pretty much everything else, it's gotta be yesterday or too slow lol. I'll try your design shortly. Currently i'm printing 1lb tube supports at 6.5 hours 4 each side. Actually got another to put up in a bit. 'Whirly Dirly' the fins are much broader but they're not angled on the vertical axis, which I may implement later. These 2 were done using Benny mix. I believe it's the spin that's imparting that particular sound but not 100%

 

https://youtu.be/wG10Dd1edVY Ignore my buddies comment... lel

https://youtu.be/IssvABPx-io Second test using Whirly Dirly assembly. reasonably straight at least.

 

I'll put link up 4 Whirly Dirly assuming interest.

[6afraidof7]

Looks good, I have thought making / using fins, may give it a try seeing your experiments. Here is a link with some info on fin designs that I have thought about using to design something simple: https://apogeerockets.com/education/downloads/Newsletter442.pdf

[SharkWhisperer]

Looks good, I have thought making / using fins, may give it a try seeing your experiments. Here is a link with some info on fin designs that I have thought about using to design something simple: https://apogeerockets.com/education/downloads/Newsletter442.pdf

Fins are fins are fins. "Still experimenting with upswept fins" cuz they look cool, ffs. Brother, fins are a friggin science, with some very basic attributes 6A7 linked you to. You're friggin guessing what physics has already demonstrated. The basics are not all that complicated.

 

"did a backfilp and went horizontal...". Cheezus

[Richtee]

Fins are fins are fins. "Still experimenting with upswept fins" cuz they look cool, ffs. Brother, fins are a friggin science, with some very basic attributes 6A7 linked you to. You're friggin guessing what physics has already demonstrated. The basics are not all that complicated.

 

"did a backfilp and went horizontal...". Cheezus

Well, there’s a certain amount of fun in that too I tried a launch rod/stick free last year. 3 loops before directly into the ground. Ah well. Prolly more a CG (center of gravity) issue than the fins. But I don’t have any burning desire to F aboot with it any more.

 

On edit: if it DID eventually straighten out...you may have CG issues as well...

Edited July 19, 2023 by Richtee

[Arthur]

The advantage of the stick is that it guides the rocket at zero speed, by sliding in the launch tube. By the time the rocket has left the launch tube it must have enough velocity to have aerodynamic stability.