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An Inventor's Quest for the NHL Pt. 37
Mixed Results and Another Redesign
This series follows my attempt to develop a product that I dream of getting into the elite levels of hockey. Previously on the Quest: Part 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, Concept Launch, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36
In my last update, I showed you the new frame, freshly welded.
To finish off the cage, I laced Dyneema rope through the frame’s bars and stitched the intersections with Kevlar thread. Test dummy Bob checked my work and volunteered to try it out.
Five shots later, Bob was traumatized yet again and I was left with a broken cage.
After a thorough investigation with a toothpick, I felt a tiny divot in the steel in the area where the rope had broken. Guiltily, the divot offered up a fiber from the broken rope, so that, at least, I wouldn’t have any doubts about the point of failure.
Doubtless, I was still worried. I needed the cage to be robust enough to handle unforeseen circumstances on the ice and in the hockey bag, and instead, it failed catastrophically because of a small manufacturing defect.
The only reason for optimism was that the current rope would eventually be swapped for a tougher double braid kind. But as I stared at the broken rope and imagined the consequences, the gap that I’d been trying to bridge for so long - between prototype and product - felt more like a chasm.
I had my usual existential crisis, and then I went on Amazon and ordered some sanding and polishing bits for my Dremel. My level of belief hadn’t risen; it just felt like a shame to go through all the effort of making an entirely new frame and not seeing what it could do.
So I sanded and polished as best as I could, trying to give the rope no excuse to split.
And fifty shots later, the rope remained intact and unfrayed. That’s up there with some of the best results I’ve had from any of the previous cages. (I’m sure you could tell that just from the sheer happiness in my tone.) The bad news is that the frame bent.
I could’ve kept testing but there wasn’t much left to learn. Once again, the concept showed both promise and flaws. It’s better than the last one, but it’s only a modest step forward – and really, I needed teleportation.
I had a few options to consider. First, call it quits before my October 1st deadline. Second, keep improving on this concept. Third, try one more, completely different concept.
The second option was the least attractive. I could improve the yield strength of the frame through heat treatment or generally beefing it up, but nah. I’m not even going to try to make up a technical-sounding reason, because the truth is I’ve never really loved this particular design and was only too happy to have an excuse to move on from it.
The first option was as enticing as always. I’d at least save my beard from a few gray hairs by finishing a month early. But there was still one idea left rattling around my brain, so this project will finish the way it began: with me making something to get it out of my head.
So what is this idea?
Essentially, it’s to connect the ropes as directly to the helmet as possible. Back when I was having problems with the crossbar, I got rid of the crossbar. Now, I’m having trouble with the frame, so why not get rid of the frame?
I think this idea would work best if you could design the helmet from the ground up to support the net – focusing on stiffening the face hole so that it doesn’t collapse under the tension of the ropes. But, as much as I’m a fan of bold ideas, single handedly designing a helmet from scratch in a month is a little too bold for me. Instead, I’ll stiffen my existing helmet as best as I can.
As for the connections to the helmet, which will be 3D printed out of Nylon, I focused fully on the rope’s path in the design process – paving it with generous radii and laying it as straight as I could on a complex-curved surface. That was a challenge. In fact, it took me seven hours of work in OnShape, which you can enjoy in one minute.
The results though, I think, were worth it.
Let’s see what happens, shall we?
Thanks for reading,