comments, suggestions, anything? been staying away from this topic for awhile, was scared of people stealing designs, so i’ve been kinda doing my own thing. therefore haven’t had anyone to check my designs.
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All this talk of balls and cups you’d think this was a kendama forum
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and finally bimetal. made a titanium as well, but i want it to be a surprise when i release it. (sorry jordan, just replied to you because otherwise discourse won’t let me)
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The outer edge of the rims looks really sharp!
I don’t think anyone is interested in stealing unproven designs, by the way. It’s definitely something that happens for really successful ones (like the draupnir) but I think they typically do that by reverse engineering the whole thing in a machine shop with measuring tools.
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That looks really extreme. What’s the weight ring/body weight ratio?
I’d consider going over it again to make sure all of those undercuts are machinable & the material isn’t too thin.
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Cool design, but I’d just be nervous throwing this one.
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how so? do you think your hand would hurt on the catch, or something else?
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haven’t sent it off to a manufacturer yet so idk if it’s machinable, but its made of 7075 and every wall is at least 1mm. body is 15.3g, rim is 15.8g. idk if that’s a good ratio, but hey, it spat out a decent moment so 
and for the monometal, didn’t catch that for some reason. i’ll update the comment with new pictures once i fix that.
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Yeah, sharp edges like that just unpleasant to play in my experience, it kind of reminds me of the Lesula. Personal preference of course, i’m sure some people will love that shape.
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yeah, i getchu. of course, handfeel hasn’t been tested on any of these because i haven’t proto’d them yet, so there’s a chance that none of them are comfortable.
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You can make the rims bigger, And make the stainless steel more round. Only problem would be the weight if the rims were bigger 
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That’s a lovely pipe under that monitor! Nice to see a fellow pipe smoker here!
My bad didn’t realize how far back in the thread I was… still learning this forum lol
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Also that’s not @knowledgeablepixels’s photo, it’s from the people at A-RT.
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So a couple of things on this design,
You mention that all walls are at least 1mm thick, this is very thin for Alu, especially in high stress areas.
For 6061 you want to have all walls at least 1.5-1.6m thick.
If 7075 you want to have at least 1.2mm thick.
I would also agree that the outermost edges of your rings where they meet the Alu body is going to be very uncomfortable on the catch, as it forms a point. Consider rounding this off considerably.
The ratio of weight ring to body sounds like its about 50:50? this is really high, with all the weight out near the rim your throw is likely to feel very heavy and extremely powerful on the string with a real kick when it binds, this in combo with the edges angled towards the hand is going to be un-comfy and possibly split eyebrow inducing. Consider flattening and rounding off the rim edges considerably. Both to reduce the ring weight and add comfort and safety.
Finally, i’d suggest a higher fillet radius for any of your cuts that will be in near the walls around your undercut, sharp edges here can saw at your string and create bad times.
Keep up the good work!
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thanks a bunch man! and is there an ideal ratio between rim and body weight for bimetals, or is it still mostly dependant on if the moment checks out or not?
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The ratio of weight (and the related moment of inertia) depend on a couple things.
- What feel do you want? Who is the yoyo for?
- What performance characteristics are you trying to get?
And of course, other factors in the design affect all of these. Wider/narrower gap, the profile shape, the width, the diameter. If you look at yoyos you know you like and figure out what you like about them, you can sort of work your way towards numbers that make sense for what you’re trying to accomplish.
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I know all of that stuff is what you’re supposed to do to get a desired feel, but I decided that my (our?) Companies design policy will be make a shape never made before, proto and see how it feels. It’s such a sad mentality that all yoyo designs have been done before, so I want to prove the people who think that wrong with the throws I produce.
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of course i still want it to make real sense, but the first priority is a never seen before shape.
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This is a fine idea, but I think your design is trying to do too much at once - I think the rim/ring is already distinct enough that you should try to simplify the cup so it doesn’t draw attention away from the part that really matters.
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