Free Butterfly Fins - Limited Offer

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wcravens

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In my daydreaming about how in the heck I was going to line the fins up correctly on my Photon Probe I came up with my new tool. Well it's new to me, if anyone knows of something similar please let me know.

I went to the lab with three designs in mind. The first two were disasters and hard to use but the third (which I didn't start off with much hope for) turned out to be really simple to use and very effective. So I call these the 'Butterfly Fin Guides'.

066_Attaching_Fin_Sets.jpg


You need to use your own aluminum angles.
067_Attaching_Fin_Sets.jpg


I cut these out of 1/8 because we were having issues cutting 1/4. Our laser in the lab needs to be replaced. So I grouped them into 4 sets of two. I like them this way and I could easily glue them together if I ever wanted to.
068_Attaching_Fin_Sets.jpg


You secure the Buttery Fly Guides and the aluminum angle stock all together with rubber bands.
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I don't have a good shot of it, but I used some scrap balsa in between the two angles to hold them apart in parallel. And an other rubber band at the aft end of the angles to provide a little bit of 'pinch' to hold onto the fins. The fins should fit in between the angles with a little friction. If they don't then just a little bit of paper will provide a great shim until they fit just right. I dry fit the fins with the guide in place on the body tube to make sure that they are all going to glue down in the right position. Then remove the whole unit, apply glue and then put back into place. An other trick is that you can look in between the angle stock to sight up the fin alignment marks.
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To make space for more fins I used a rollup table mat to hold it in place over the edge of the table.
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Once you have got the guide and fins lined up just right you can apply more rubber bands around the body tube on the Butterfly Fins. This then frees up your hands to fine tune the alignment or anything else. It also means that when your daughter knocks it over coming over to have her breakfast and help daddy write this post, then it isn't a total disaster.

074_Attaching_Fin_Sets.jpg

Ah Eureka; That rolled up matt was totally unnecessary. Just flip the whole thing onto it's back and it sits on the edge of the table no problem.
075_Attaching_Fin_Sets.jpg


Ok - Since you have all made it this far and are still reading, I will send you some of these for Free! (Limited Supply, first come first served) Just PM me and I'll make arrangements to send some to you in the mail; totally for free. I'll just ask that you use them and provide me some feedback. I'll put more details in the PM exchange to make shipping arrangements.

I'm going to release the drawings, patterns, and files that can be used for laser cutting under Open Source/Attribution/Copy Left licenses but I can't do that here because the Terms of Service are in conflict with the licenses that I will use - but once I put up the website they'll be available.

I'm really pleased with how this has turned out. There was a learning curve while I got used to it, but that abuse was taken out on the Partizon and Big Daddy that are on the bench too.
 

Creeps

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Looks like you've got a winner on your hands.
 

blackbrandt

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PM sent. Hoping to use these at a CAP rocket build session. ;)
 

dmgrime

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PM sent. Heading into a long Northeast winter, so should have plenty of time to put these through their paces!
 

mjennings

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took me a moment to figure out what was going on then, it was wow that is fantastic!
 

les

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Nice - PM sent
 

wcravens

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WOW! Holy Butteryfly Fins Batman! You folks are amazing. I really wasn't ready for this. But I'm not one to disappoint so I went and cut a _lot_ more. Everyone I have a PM from at this point will get a set in the mail soon.

Some folks have very kindly asked if they could contribute something toward the costs of this endeavor. All I really wanted was a few people to help me refine the idea. But these offers got me to thinking about an other idea...

I want to promote the creation and open sharing of designs and information for our hobby. If you're familiar with Copyleft and Share-Alike licensing then you'll get it. But the idea is that the designs can be freely used and extended but attribution would always flow back upstream. Wikipedia is built on this free (as in freedom not as in money) idea. There could even be a marketplace where people could voluntarily donate when they choose to use a design. Of course this wouldn't be required but it sure would encourage people to provide more designs and innovations.

The site would also promote those developers and innovators who have already adopted this model. Altus Metrum, OpenRocket, Rocket Track, Tracksoar APRS (look it up on kickstarter), etc. (if you know of more open license solutions in our hobby please let me know).

So with that. Everyone will get your set of Butterfly Fins and I'll include details of my new website idea (hopefully it will be ready by the time you get your fins). If you like the fins and would like to contribute to the site it will have instructions on how to do so. But please don't feel obligated. I said free and I meant it.

Thank you all for your support and interest. I've had a very rewarding day!!!
 
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Screaminhelo

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I would gladly contribute my friend! You have come up with something the I see as a brilliantly simple solution to fin alignment. It is something that can be made with minimal cost and, if it were sold, would utilize metal angle that many folks already have on their bench.
 

rharshberger

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Definitely a neat idea, one of the neatest features is it break down so you don't have a large jig or fixture sitting around your build area. Don't get me wrong about jigs/fixtures, I LOVE my Guillotine Fin Jig, CR slotting jigs ( I like fins that slot into CR with TTW), Tube Slotting Jigs etc. But this system is so compact I can even put short aluminum angles and these guides into my range box for in the field repairs.
 

dmgrime

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These look very cool indeed. What thickness aluminum angle do you have them grooved for?

It seems the 1/16" has enough twist to be problematic, but I want sure if the groove that engages the aluminum angle would go over 1/8"?
 

wcravens

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They are 3mm but have not been adjusted for kerf (the width of the laser) so they are just slightly bigger than 1/8"(3mm). I've been using them on 1/2" x 1/8" angle.

Wes
 

dmgrime

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Perfect, thanks! I was hoping that was the case :)
 

mjennings

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tried to send follow up PM and it says your inbox is full
 

wcravens

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Again folks... thank you all so very much for your support and encouragement. I only had 4 sets to begin with, but 20 sets are going to the post office tomorrow morning. If you sent me a PM, and didn't get a message about me running out, then your Butterfly Fins will be on their way tomorrow.

In the package I have included a shameless plug for my new website idea. Please have a look when you get it.

For the rest, I will be getting the site ready over the next couple of days and I hope to have it ready for you to be able to get your own set of pre-cut Butterfly Fins. Keep an eye on this tread for the address later this week.

For those of you with access to a laser cutter, all of the source files will be available on the website also. However we will be encouraging support of the site by donation if you do decide to use the designs. All in an effort to pay forward on the project.

Sorry I didn't manage to move faster on getting these out. This last weekend was a road trip for my son's birthday. And he didn't even choose the local launch day... geesh!

Thanks again everyone,

Wes
 

Screaminhelo

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Looks like you found something that folks are a bit excited about...or do we just want free stuff?
 

wcravens

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Looks like you found something that folks are a bit excited about...or do we just want free stuff?
I'll admit that the kind words of encouragement from most folks has been very welcome. As for people just wanting free stuff... we'll find out soon enough. :)

Wes
 
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