Griff
(Well crap, my hypometric precursor device is blown…)
1
The internal crank shaft that opens and closes a large market umbrella in my back yard shattered. It appears to be what I’ve always called pot metal. Maybe Zinc? Zinc alloy? Anyway, crap!
Naturally I cannot find a replacement part, who repairs anything, right? Well, I do. The umbrella is only a few years old and in very good shape.
First, here’s the F360 design I slapped together. (You must remove the .zip extension to open in Fusion) umbrella crank connector no screw hole v1.f3d.zip (146.9 KB)
I printed a prototype in PLA, made some adjustments then printed one in PETG and another in ABS. Both broke at the base of the hexagonal part of the shaft. 100% infill BTW. I’ll try another in PC but am not too optimistic.
So, why I’m here. It seems I should be able to machine this but it’s way beyond my mostly 2D CAM experience. A little help would be much appreciated.
Not that I can help but did you see Winston’s video where he mills a 3D figurine by turning it on 4 sides? Maybe you would find it useful for the F360 and milling info it provides.
@Griff Before you abandon the 3D printed solution, try printing it on its side. I know it’ll make for messy supports, but you’ll be much less likely to break it.
It would still eventually fail on you, though.
4 Likes
Griff
(Well crap, my hypometric precursor device is blown…)
4
If you don’t want to do this as a two-sided job for any reason, since this thing is about 7cm long, crazy me could imagine doing this as two separate simpler 2.5D parts, 3.5cm tall, with a screw to hold the two pieces.
You would need an endmill with a fairly long LOC, and a pretty thick chunk of aluminium stock though. But the CAD and CAM would be easy.
2 Likes
Griff
(Well crap, my hypometric precursor device is blown…)
6
So, I took your advice, sort of.
I designed a two piece part to be held together with a 6 mm threaded rod (a socket head with the head cut off).
Cutting the first half now out of 6061. We’ll see how this goes.