dorbie

How would you get the cables inside the helmet and assure a smooth pull? The mount design is nice, it does look identical to the system Chutingstar offers; a cutaway would make a big difference. There would be a permanent portion of the mount on the helmet and a detachable cutaway portion attached with routed cable. I was not considering a cutaway inside the helmet, rather some type of cable loop you could pull that was on the mount itself. It would only detach the top portion of the mount with camera leaving the base plate in place. What chuting star mount are you referring to? The Square1 design? That is a single part design in two variants, flat base and curved base.

Hmm... that Square 1 mount is not detachable with 2 parts. I'd say they're pretty different except in the most superficial sense.

This is just a concept at this time, I might make the 3D models available but I'm not going to productize it. Given that the requirement is a snag-proof box around an identical 3rd party swivel bracket & camera mounted on a sphere there are going to be similarities. I can't 3D print a product I don't have the model for and this is just a personal project to create something that suits my needs. My design is larger than it needs to be because it started out encompassing the existing mount, I'll probably change that.

The latest iteration: http://youtu.be/f7zKktRTJN8 It would lock with a simple pop latch at the end of the slide and so be easily detachable (not modeled here). It's probably a bit bulky for a gopro mount as it evolved from a mount to encase the existing mount. I have another idea to simply use two cutaway cable channels to mate the two halves and give a quick release in one pull. I like that plan.

It's also a great example of the perils of offering expert advice online. For the record, DSE was correct about distortion. What a choice! Educate someone who's quoting consumer pamphlets at you so they're better armed the next time they spread nonsense or walk away.

See DSE's comment. A layer of double sided 3M adhesive between the helmet and the mount could do the trick, provided there's enough surface area under the mount. There's no point in having external tape when you can tape between the mount and the helmet.

There's still a place for a shroud that goes over an existing gopro mount. If it permits quick detatch from an existing sled via a rear opening or door I'll have some use for it.

Thanks, if you see the latest version I added some flanges on the inside for screws but not enough surface area for adhesion as you say. I did try to model a broader base with a larger diameter circular foot to increase the radius but the boolean geometry operations failed at the time. I now know it was a surface direction problem that I have fixed. Any additional suggestions would be welcome. This one seems pretty good - and not too expensive. http://www.sculpteo.com/en/print/rawa-vision-mold15/yYEjKU4k?uuid=NuwSU6e0JSyWlyi5lxg7Wf Hmmm... I might be wasting my time :-) That's an improvement on the original mount. Perhaps I should just tear off my existing mount, I'm starting to regret my use of JBWeld :-) Let's see where this journey takes me. I have some flanges to add...

I am using the freely available Blender, I imported the vanilla gopro bracket shown in black in the first video from an online free repository of STL files for 3D printing and used that as a guide.

Exactly this. I don't think the flanges need be large, and they can conform to the curvature as well. The same flange one might use for a nylon screw would be useful for the person who prefers VHB, no? Yes, any flange geometry could house holes for screws.

What flanges did you have in mind, You're talking about strip tape right? So linear edge flanges on the inside with a helmet conforming spherical curvature right? A concern is helmet radius fit... Alternatively I could add circular feet.

Thanks, if you see the latest version I added some flanges on the inside for screws but not enough surface area for adhesion as you say. I did try to model a broader base with a larger diameter circular foot to increase the radius but the boolean geometry operations failed at the time. I now know it was a surface direction problem that I have fixed. Any additional suggestions would be welcome.

Never underestimate the utility of gaffer's tape.

That is theft. I proposed a case on a standard sled above but if you give it some thought as they undoubtedly have you will realize that a standard mount is linear and a helmet spherical. This makes a tight fit on two axes impossible without an additional mechanism like the cam I mentioned in my comments.

One possible mount option: https://youtu.be/PRMP6Z5vp18 Still needs a lot of tweaking... By no means final, just exploring ideas.

Not really, the Square one has the integrated mount with no quick release. I had considered adding that swivel (may have discussed adding it in my comments). This thing will go around an existing M3 mount with one mounting option under consideration being rubber bands. Not saying it's better of course, just different.

I'd like to use my existing mount for other reasons (e.g. helmet bag) and just slide this in and lever it down with some kind of cam. That is a much fancier design, also my JBWeld is slightly lower profile than a 3M pad making this less useful without an adjustment. A working mechanical design for that cam lever would tax the software I am using and my skill with it. There's also something to be said for avoiding that complexity.... but I have a helmet bag to fit this in damn it.

I have 2 ideas in mind: 1. Have recessed notches that you can loop rubber bands to under the gopro case that will hold it against the helmet. This would pull down against the goro (the reaction force on the gopro would be to pull up away from the adhesive tab. A couple of rubber stow bands should suffice. Would an M3 pad hold tight enough? Mine is JBWeld so it is not a problem for me. 2. 4 lugs to screw it onto the helmet at each corner and add the sled required to mount it. The idea would be a flat head and a washer on the inside of the helmet and a hex retainer in the hole to catch the nut with a rubber washer sandwiched at each corner to assist with the mating and stresses. This might need a door at the back and a bigger panel I think but this is doable. There are other ideas but it gets complex, and I do not know what others would prefer, I can only spitball what works for me at this point. Another factor is the tilt, this thing tilts to match my pref but folks would want to vary the angle on their setup making this less useful to a broader audience. The other consideration here is that the curvature of the base will not work for every helmet. Right now it is a guess but if I curve it for my KISS that might not work for anyone else. In fact it may not work for anyone who mounts it anywhere else on their KISS helmet. So this is making me consider 4 feet that would be slightly angled. It would still curve but only each corner would mate well with a helmet using a rubber/neoprene shoe or washer and leave an arc underneath giving less opportunity for a line to get under a corner regardless of helmet geometry, but it would not be conformal.... Something like a neoprene gasket would work for me, maybe not any other helmet though. I think I could combine both the feet, the screw lugs and the elastic band loops and a door (optionally) to give all options to everyone although the sled would not be integral. Everyone has a sled already anyway. Too many options really, none showing in this design as yet.

Well the price of "free - 3D print it yourself" might work.

The hole is for screwdriver access, other ports could be added for finger access, but I'd rather keep it clean. I could also add enough space to remove the sled but this started with the idea of attaching by hooking under the camera, I think I will ultimately go that route so it would be detatchable rather than permanent.

This is the first pass, the idea being to 3D print the red part and use it as a shroud around a mount. This matches my specific configuration Others may prefer a different angle to their dangle. I might make this available at cost on shapeways, but probably not, it's not worth the liability. https://youtu.be/tETptjfS0PE Access might be awkward with a permanent attachment so I was thinking a couple of recessed attach points for elastic bands may suffice, but a firm slap could move it and temporarily open a recess. The bands would also exert a steady force on the mount so a permanent bond at least on the mount would be preferable. Anyway, it's better than a bare mount IMHO.

Very brisk opening but very consistent and confidence inducing, but it is firm. It does have a weaker flare mainly because there's not much second stage, or to be more specific not much stroke left to generate additional lift as the induced drag bleeds off your speed IMHO. There's more than enough flare to stop your descent, if not you're doing it wrong. Jump it and make up your own mind. The other advantage is pack volume, you can fit a size larger main in your rig to upsize a bit if you need to.

I think perhaps he read too much literal into your remark but I don't think he was being unreasonable or pedantic. When he discusses lift in the context of a parachute and a barrel roll it's absolutely appropriate. He's spot on with his observation that a parachute in these scenarios is still generating enough lift to sustain positive G forces on the jumper. His suggestion of a center of rotation above the CG as a definition is insightful but probably either an emergent property or requirement of any barrel roll. A possible distinction I think is the importance of the pendulum effect or rather the sustained angular momentum of the skydiver under the parachute and resulting centripetal "force" loading the wing in opposition to the lift, but they're pretty equivalent maneuvers IMHO, because this centripetal force also exists in a fixed wing barrel roll when I think about it.

Dibs on your bounce rig.

You mean unimpressive now, or for initial production in 1991?