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Member Since 11 Jul 2008
Offline Last Active Mar 03 2020 12:20 AM

#362361 OpenChrony - open source, DIY chronograph

Posted by TantumBull on 25 January 2018 - 07:49 PM



I’m calling it OpenChrony. It’s an open source chronograph, compatible with nerf and paintball. It is Arduino-based, and the code is publicly available, as are the part files (.stl, .step and .sldpart coming soon). I’m hoping that others will improve the design, this is only the first functional version.




Attached File  OpenChrony V1.5 Writeup.pdf   1.46MB   1315 downloads







Attached File  OpenChrony.zip   751.42KB   821 downloads


V1.0 Video





Attached File  OpenChrony1.5f.zip   753.69KB   693 downloads



Updated part files coming soon

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#346721 Quick Exhaust Valve Homemade Airgun v1.0

Posted by TantumBull on 13 May 2015 - 11:28 PM

I went into a gentleman's agreement NOT to post internal pics

Because rigging a few pneumatic components will obviously get you intellectual property rights to the idea, and its super marketable. Or maybe it's that easy in Australia.

I9: I like it a lot. Quick question about print settings, though if you got the parts from Ryan this might be more directed at him. Mind telling me the print settings (shell layers and infill percent)? Also, I'm assuming PLA since its most common and ABS doesn't offer many mechanical advantages over PLA when its FDM printed (different story for injection molded). Also, you might consider putting the bolt holes a little far farther from the edges on the handle assembly (mounting bracket and the grip itself) as you're introducing some significant stress raisers that could reduce your fatigue life. I'm not sure if the stresses involved in normal operation go above the endurance limit for the design, but it's something to consider (iirc PLA/ABS have fairly low endurance limits).

I ask because I have extensive experience with FDA printed PLA but am curious to see how it holds up in situations with higher loading than I've subjected my parts to (which are for non-nerf stuff).

Again, great stuff, not trying to nitpick at all. Just something to think about for V2.
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