A question to manufacturers about yoyo weight distribution

Hi,

As some of you may know, I make wooden unresponsive yoyos and I have a question about weight distribution.

Wooden yoyos I have made out of wood that are W shape and wider (about 43-44 mm) tend to have a huge amount of wobble over their organic counterparts. I believe this to be that the wide angle of them reduces the mass around the response area which accentuates the inconsistencies of the density of the wood where most of the mass is located; i.e. the rims.

My question is (and I will test this myself) would placing most of the weight in the middle of each half reduce the wobble significantly? Thinner wooden yoyos I make tend to have vibration levels that would even be acceptable in metal yoyos. So I’m thinking, that to make a wide w shaped yoyo with the desired width, I need to create a thin and deep lip, then concentrate the mass a little further in rather that right on the rim.

Does this make sense?

If you are an experienced yoyo maker, please let me know your thoughts and suggestions.

Below is a picture of a wide and wobbly yoyo I made last night.20180922_220440 20180922_220439

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Amazing! Interesting question and theory! More reduced walls with as little carved from the cup might do it. Beautiful yoyo!

This one is one I made earlier than the above yoyo. It’s the same width as the other one, but the weight is shifted a tiny bit further into the cup beyond the thin lip.

This one has far less vibration, but the sweet spot for tuning is extremely small.

Maybe shifting the weight in a little further was whay helped this one?20180624_223421

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Is it possible to carve the center without a lip, or maybe leave a little lip before the spin cup. The carve I am talking about is more of a cone shape with the only flat part being the axel and lip. The outter walls on that are more a long the lines of what I was thinking.

Do you have any yoyo making experience?

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From my experience and what I’ve heard others say, the wider width will bring out more of the inconsistencies. I think you came up with a decent potential solution (add more center weight). I think that would help. It probably wouldn’t take too long to test out your hypothesis either! :slight_smile:

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More mid-weight is what I’d call it. I’ll put the bulk of the weight around 5 or 6mm into the cup.

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I am too poor to make yoyos. I tinker a lot. What you showed and said was enough for me to ponder.

Yeah, me too.

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You are most definitely on the right path. I showed my brother your works. He said that it is something he would pay top dollar for just to have it displayed on his wooden coffee table just because. It was all hype talk, we don’t got it like that, but if I did. You’d our Starbucks and we be your over privileged United States Citizens patron!

I can hardly understand what you’re talking about.

But I like you!

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I’m not a manufacturer but here’s what might be happening. Dipping into a quick physics visionalization…

If you view the profile of the yoyo (so you can see the gap), imagine a see-saw placed along the center, with the axle/bearing assembly as the fulcrum. All of the weight of each half is laid out on both sides of the see-saw. Now, if you apply a force close to the fulcrum, it’ll be a lot harder to move the see-saw than if you apply that same force at the very end of the see-saw.

In a wide yoyo, the see-saw’s arms are longer, so any imbalance there (from the non-uniform density of wood) will have an extra-big effect on the balance of the yo-yo, compared to weight placed closer to the fulcrum. This is also true for weight farther from the axis, eg. rim-weight.

I think this is why, when you carve out some of that rim weight, leaving it more center-weighted and close to the axle area, you are getting better results.

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That looks familiar! Is that mine? I’ve really enjoyed mine!

I’m not a manufacturer or maker either, but here’s my 2 cents:

How many of the wider, more rim weighted version have you made? I would think you’d need to make several to really get an idea of how sound the design is. It will probably always be a trade off of potential performance gained vs how many you deem as unacceptable. I remember seeing a pic from Jensen of a whole box full of discarded peon halves… The more aggressive you are with width and rim weight, the higher the percentage you’ll have that are unusable.

I also think that if you really want to go for more rim weight, it might be better to focus on slimmer designs. You may find as you experiment, that the wider designs do in fact need to be more mid-weighted, as has been already discussed here.

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That’s a fair call, but I think I have good reasons to believe my theory even after making only a few wide rim weighted wide halves.

I used a length of wood that has produced very consistently smooth yoyos with minimal vibe. The choice of wood overall was one with known relatively uniform density.

The wobble difference between the thin rim weighted halves and the wide rim weighted halves was so extreme it must have been an design error rather that a material consistency error. I believe this also because I have made wide halves of the same width and material and the ones with less rim weight weight wobbled far less.

I’m almost certain that if I lessen the rim weight and move it closer to the center it will be much smoother.

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I just made this one. It’s not exactly W shape but more of an organic/W.

I kept it the same width as the wobbly W one I made and made the adjustments with the lip that I thought would help.

It really did help. It’s a really smooth yoyo. Really nice feel on the string.

20181006_191400

20181006_191420

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You should be keeping specs of what worked and what didn’t with wooden designs. It might help you find aspects or ratios that were not thought of while brainstorming. I do believe every shape can be achieved without wobble & minimum vibe. You will eventually figure it out. What is perceived as an error on one shape type might stabilize another shape type. Just a random thought.

Part of the wobble might result from how it fits in your hand?
Can you smooth out the wobble when it’s spinning after the throw?
I think of the wider yoyos I have and I don’t get a smooth throw more often than my organic shaped narrower ones…

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