Since washers don’t really fit on mad4one frames, I decided to make these small spacers, so I can finally not get annoyed with the bearing caps anymore. I printed these at 2.6mm thickness (ended up measuring slightly under that) and can’t feel any play when the bolts are fully tightened down, but the wheel still moves quite freely.
As the saying goes, “If the only tool you have is a hammer, it is tempting to treat everything as if it were a nail.” Or in my case: “If you have a 3D printer, a 3D printed part is a solution to any problem, if you look at it long enough.”
But here are a few reasons why I went with this over cutting a washer:
very easy for me to get the right (and equal) thickness for every washer with very little work (takes 2 minutes to adjust the thickness in CAD and start a new print)
No need to buy washers
No risk of rust
I can now replicate these at the click of a button and give them to others (might even make a few different thicknesses for that purpose)
while not strictly necessary, it’s neat that these are the exact shape of the bearing holders
I usually remove my cranks before flying to UNICON and to reduce the wear on my bag in the spot that my ISIS spline rubs, and cover the spline to reduce dirtying my clothes I 3D printed an ISIS cap that would sit over the spline before being held in place by the crank bolt. It worked for the intended purpose.
Despite being printed out of Nylon I rather expect them to fail, especially as I’ve used them in stamped bearing holders in a frame that has been widened (bent) so the holders are slightly off-axis.
I’ll probably end up printing some more, maybe even in a solid TPU, or adjusted so that they themselves are off-axis to account for the error.
Ok guys, I’ve got too many project too follow. Is there any brave fellow who will 3D print a saddle? The idea is to make a saddle with the different compression idea used in cheapo (and comfortable) AliX saddles…
It will be the lightest saddle ever made, cheap, 3d printable, with holes allowing water to flow and dry to clean mud.
I don’t have time to learn how to make a 3d file, to have my wife agree to buy a 3d priter, and so on… does anyone could do it for the unicyclis world?
I’d be happy to print some (and buy the most suitable engineering filament) if we can collectively come up with a design that we want to see.
It seems that the commercial ones are probably injection moulded ABS.
I sadly don’t have a Handle Saddle to mount it onto though, and my mesh modelling stills are certainly mediocre at best (such a saddle would be moderately complex to model parametrically).
I don’t know whether that’s a particularly good idea, but if it fails less often than Quax’s Qaxle bearings, I’d call it a win. Thoughts?
edit: @Eric_aus_Chemnitz also spotted a bearing dimension even closer, 25x42x9, though there it’s the inner not the outer diameter that needs a shim plus another shim for the width. Sounds better, doesn’t it?
As Qu-Ax’s frames (mostly) have the bolt positions offset from the bearing centre, as much as that 7mm bearing seems narrow, it would probably put them in about the right position.
It’s probably not a good idea in plastic, although in aluminium like the KH bearing adapters that you can buy/used to be able to buy it might not be so bad.
Maybe. The inner shim is probably easy-ish to make, from some 0.5mm sheet stock, and then the spacer can be pretty much whatever you like so long as it’s non-compressible - 3D printing a solid part would be fine here. Again the offset of the bearing should be no problem with the Qu-Ax frames.
It seems HDPE typically has poor layer adhesion and issues with warp, so although I can almost certainly print it (I’ve 3D printed POM, and pure PC with reasonable success), for something quite slim, large, and moderately complex it certainly wouldn’t be easy, and a single iffy layer would cause the whole part to be scrap.
Sadly the ones I had 3D printed seemed to break quite easily, they don’t appear to like backwards UPDs.
Anyway, I took a broken one to a local CNC company (and emailed them your CAD file) and they’re making six for me from aluminium.
I don’t have them yet, but they’ve just sent me this pic of the first two, and they look fantastic.