3D Printed Fins

One-Off

Tom Curren status
Jul 28, 2005
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Which NACA foils are you using?

I'm not good at math but. herein lies the secret to good fins.

This is basic first year stuff for aeronautical engineers. Just to show how "seat of the pants" surfboard design is.




Screenshot 2022-12-18 at 11.41.03 AM.png
 
Mar 27, 2019
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Instead of molding, since fin proven, now get CNC cut G10?
Ultimately, this is what I will most likely end up doing.

I like experimentation though...

The mold is almost complete. Waiting for chopped carbon and fiberglass to arrive. Planning on using RR Epoxy for the mix. Also have a spool of Carbon infused PETG ordered, to try on another printed set.
 

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sdsrfr

Phil Edwards status
Jul 13, 2020
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San Diego
Which NACA foils are you using?

I'm not good at math but. herein lies the secret to good fins.

This is basic first year stuff for aeronautical engineers. Just to show how "seat of the pants" surfboard design is.




View attachment 144145
Year one aero eng’s learn to read NACA tables.

They don’t do much on the equations themselves aside from chug and plug.

Changes if you’re talking about a grad level program.
 
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The Carbon PETG prints look good. They have a good, solid, strong feel to them. For those not familiar with 3d printing, the objects are not usually solid material. The core of the fins I am printing have a cubic core, and the density can be adjusted. I'll have to make a standard twin set for the Twinsman, as that may be a better testing ground for the fins, rather than a Mini Simmons. On a side note, I yolo'd a desktop CNC machine. Waiting for parts to modify it out of the box. Cutting my own fins out of G10 is near future.20221222_081732.jpg20221221_193010.jpg20221222_083828.jpg
 

Aruka

Tom Curren status
Feb 23, 2010
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cool sh1t Jamby. how much does a desktop cnc machine like that cost?
 
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cool sh1t Jamby. how much does a desktop cnc machine like that cost?
The CNC was just under $200. The Makita router I retrofitted to it was $130. The Dewalt Vacuum was around $130. I probably went through a couple hundred on miscellaneous accessories and bits. It takes roughly 2.5 hours machining time per fin, but I have plans to build a larger/more ridged machine, that will drastically cut the time down.
 

Aruka

Tom Curren status
Feb 23, 2010
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The CNC was just under $200. The Makita router I retrofitted to it was $130. The Dewalt Vacuum was around $130. I probably went through a couple hundred on miscellaneous accessories and bits. It takes roughly 2.5 hours machining time per fin, but I have plans to build a larger/more ridged machine, that will drastically cut the time down.
very cool. you do stuff like this for a living is it just something you're interested in?
 
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very cool. you do stuff like this for a living is it just something you're interested in?
Nah, it's just a hobby. I like to build stuff when I can, and if I can apply it towards surfing, it's a huge win for me. I love riding different shapes, and if I can make my own fins... that will really open things up some.
The 3d printed carbon fiber prototypes are hanging in there. Probably have a dozen sessions on them now. Light as a feather compared to the G10's20230207_224152.jpg