Designing and 3D-printing a garage remote motorcycle mount
stavros.io
stavros.io
Whilst it doesn't have all the features of the usual commercial packages (Solidworks etc), SolveSpace is great, cross-platform, a single binary and my preferred open source solution for simple 2D/3D cad jobs [1]. FreeCAD [2] has also come along a lot if you prefer something more like the traditional packages, although I found some annoyances with it's dimension and constraint system when I last used it ~6 months ago due to the fact it has two different sketching modes.
You're right about the proprietary/cloud nature of the previous alternatives, which is regrettable because Fusion is a desktop program, and could easily just be saving files locally.
I hope FreeCAD becomes a great alternative soon, because Fusion really needs competition in the space.
Of course the cloud systems have their advantages and uses too!
Nice project and write up by the way!
I ended up hacking a bluetooth earpiece into a remote after seeing the idea online. It was 100% reliable over a period of over 2 years.
Having it mounted in the open like that seems like it could have a few drawbacks. I would still be concerned about water damage, even if you don't plan to ever be out in the rain. What about the fasteners you used? Are they rust-proof? Things mounted on my bicycle that have any metal parts seem to wear out over time, and plastics seem to take on some weathering, possibly from sun.
The good thing about having a 3D printer is that a replacement part is just 20 minutes away.
Anyway, it would be an interesting experiment for you to stick with the PLA print until you see a problem before you reprint with PETG. My bet is it will last longer than expected.
Regardless, cool project. I'm planning to do something similar, as soon as I can get an indoor space. I might go even more hidden, and hide it under the lip of the gas tank or etc.
I was dubious at first too, when the motorcycle mechanic told me that, but then my car mechanic (completely unrelated) said the same thing, so I took all my keys out of the keyring.
Apparently, weight leads to the lock "loosening up" and can make the key "stick" a lot, unable to turn because the rods no longer align as well.
> I might go even more hidden, and hide it under the lip of the gas tank or etc.
I was thinking about doing that and connecting it to the bike battery as well, but I couldn't find a place that was easier to reach (and that wouldn't require me to lay cables all over)...
Just curious: can you share your experience modeling this? Why Fusion 360? Because it's free? Do you have experience with Solidworks or Blender or other software? If yes, how would you compare 3d modeling in Fusion vs. other modeling software?
As far as I know, Blender isn't parametric, so it's largely unsuitable for doing this kind of work. I would recommend OnShape as a very nice starter CAD program, and it's very very easy (almost trivial) to move on to Fusion afterwards, so my advice would be: If you can get Fusion for free and it runs on your OS, try that. If not, OnShape is a very capable second choice.
That's why wood screws are only threaded partway up their length. Since these screws are self-tapping, they need to account for the problem you correctly identify here, where the screw can't clamp the parts together properly because they cannot move relative to one another as the screw is tightened into place. Ending the thread partway up the screw solves this by permitting the part nearer the screw head to move freely along the shaft, so the fastener can clamp them together properly as it's tightened.
The machine screws you're using, conversely, are threaded all the way up to the head because they are not designed for self-tapping, but rather to be used in holes which have had threads tapped into them. That's why they are giving you the trouble they are. Happily, there are a few different ways to make that trouble go away!
Making the entire screw path wide enough that the screw doesn't have to tap any threads, and securing it with a nut, is one option, and as you've seen, it can work. On the other hand, you lose something in clamping force, because there's less bearing surface, and you also have to choose between machining (or designing) a nut pocket into the part, or having the nut and the end of the bolt stick out past the profile of the case.
Another option, which replicates the benefit provided by the design of self-tapping screws, is to make the screw hole wider, but only in the part nearer the head, and leave the far part's hole narrow enough that the screw will tap threads into it on the first insertion. This way, you have the part near the head free to tighten, which solves the problem you saw with your first designs, and you get the maximum clamping force possible from the screw without having to tap threads for a machine screw - and, with a carefully chosen (or trimmed) length of screw, you can also have the path end in a blind hole in the far part, so that the only part of the screw visible in the finished item is its head. (If you care, of course.)
And a third option, naturally, would be to actually tap threads into your screw holes - but you need a tap set for that, and I'm not sure there's much point. You need taps to cut threads into metal, because metal is pretty hard, and you need something very hard to cut it cleanly so that your screws, which are only pretty hard themselves, aren't ruined when you try to use them. Plastic, on the other hand, is very soft, so you're not actually hurting anything by letting your screws self-tap. You just need to adjust your design to account for it.
Hope this helps!
Thanks for the reminder, that's exactly how these designs should work, you're spot on.
On a related note - is it just me, or does the nigh monomaniacal focus lately on high-capital-investment tools like 3D printers and laser cutters seem like it might come at the cost of a lot that's of value? Like, for example, any interest at all in how to encourage and support kids coming up in places and families where a 3D printer, or a laser cutter, is about as likely of attainment as a nice little house on the far side of the moon? I don't know, I kind of feel that way, but maybe I'm the only one.
I definitely don't think this is moon-house territory, the technology is very accessible, price-wise, especially if you consider that these tools are easily cheap enough for libraries and other communal spaces to buy and make available to the public.
I'm still uncertain that the heavy emphasis is of net value, but I'll need to spend some time considering why I feel that way before I can make a coherent argument.
I can hardly fit a Bridgeport mill in a one-bedroom apartment, after all, but a 3D printer might well be doable, and even if I still can't work in metal with one, I'd still be able to do a lot more than I easily can now...
Size-wise, it's about the size of a microwave.
Thanks for the info! One last question - I'm seeing .1mm cited as minimum wall thickness in a few places. Legit or bogus in your experience? I'd love to be able to 3d-print complex light diffusers, but that just sounds too good to be true...
No idea if it would be good enough for your usecase.. Visit a makerspace or use 3dhubs to give it a try?
Also yes, optically clear prints are a no-go, as far as I know. You can get transparent PETG, but it will end up looking rather milky after printing. Here are some videos:
Thanks again for all the info! I really appreciate you taking the time.
Having 3d-printed things is pretty cool, makes my electronics projects look a lot more professional, but I still suspect if I bought a printer of my own I'd be frustrated and annoyed.
For a few months, we even had the garage door stay completely open all the time, due to some power problems.