its an aluminum hub with 3 polycarbonate rings embedded in the hub, with a polycarbonate shell extending the profile further.
1 Like
That’s what I thought. Its an intersting design for sure.
thanks
1 Like
This thing looks silly I love it. If it works it would probably be really neat to play with.
thank you. one issue i do foresee is the possibility of lots of vibe, but hopefully if a prototype gets made there wont be too much
1 Like
Just for fun, I’ve redesigned the DV888 to be more modernised.
50mm X 45mm X 66g. Haven’t finished yet.
It has a concave cup that’s subtle but should be pretty functional for DNA tricks.
When Ive done with it, I might actually send it to YYF for them to have a snicker over. Might give them some Christmas cheer. Lol.
10 Likes
I would absolutely buy a yyf x spinworthy modern dv888 lol but it has to keep a bit of a rock on a string feel or what’s the point
1 Like
Oh absolutely! It needs to have rock feel, but why not add performance to that rock feel?
I’m just going to send them the design to see what they think. I don’t think they will be very keen on it for a number of reasons. The DV888 seems kinda close to their heart.
However, they do like messing around with their classics a bit, for example, the 888GT.
1 Like
An interesting idea for a Lego-customizable 3d printed yoyo.
A lego axle would connect each half and would allow the inside of the cup to be customized with different legos just for fun.
Any thoughts on whether the Lego axle would sufficiently hold the halves together during play? The two halves can be just pulled apart. Would that be an issue when it’s spinning?
6 Likes
If it has enough depth it should hold up maybe a little bump or notch to act as a locking mechanism but in my experience those things if tight enough are hard to take out.
1 Like
1 Like
You should be able to use a technic axle bush to hold in place. It should work ok.
2 Likes
Is that a bearing seat?
Yes, the top photo shows the bearing seat.
1 Like
Just picked up FreeCAD today and started playing around with it. Took me a few hours, but I finally made my first design (didn’t include a bearing in it and I’m not sure if I did the bearing seat right). I’d appreciate any advice or comments I can get since I still have a lot to learn. Also, thank you so much Mark for making the CAD tutorials!
4 Likes
looks great, but moi seems to be on the low end if you happen to be wanting high performance out of the design. This isn’t unusual since your yoyo is 54mm in diameter (on the smaller end), mass is also on the lower end at 62.5g and the rims are quite small in diameter.
MOI is determined by how far the mass is distributed away from the rotational axis, so in order to increase performance it’s always worth trying to cram mass as far away from the rotational axis as possible.
Of course, not every yoyo is designed with absolute performance in mind, so there is nothing wrong with it in my opinion. I myself made yoyos that aren’t focused on maximizing performance, and I think they play very well.
If you’re interested in increasing moi, I’d say push the rims farther up towards the edge, or make the rims themselves thicker. I see that the walls of the yoyo are currently at 2.48mm. You can make this thinner. With 7068 aluminium, you can go as thin as 1-1.4mm but with 6061 you’d have to go a little thicker since 6061 is softer. However since 6061 is a little less dense than 7068, it shouldn’t be much of an issue.
Also when it comes to the rim area, I can see that the thickness remains constant. This could be a conscious decision as I think it looks aesthetically pleasing, but to maximize MOI, it can help to have the rim go thicker towards the edge instead of having it be constant in thickness.
As for the SS rim, it isn’t angled in a way to make fitting it viable. Keep in mind, rims and bodies are made separately and are press fit, so you need to have everything angled in a way that you can simply push it in. In this case, I’d make sure that the bottom of the rim is parallel to the x-axis.
An example would be kinda like this:
Either way, I’d say it’s a great first attempt at your first design.
4 Likes
Thank you so much for the advice. I wanted to maintain some mobility, but I didn’t realize that it was lacking in (hypothetical) spintime. I was also unsure how to go about the walls and the thicknesses overall, so I’ll try modifying the wall thickness and weight distribution. I was mostly trying to learn/setup freecad today, so I’ll try playing around with the design some more when I get freetime. Just curious, what is a good range for MOI?
For more performance oriented designs, I’ve seen MOI go around 33k-35k for both halves. So for each half around 16.5k-17.5k for each half.
However, a lot of these designs were 56mm in diameter and were around the 65-66g range.
1-2mm decrease in diameter doesn’t seem like a lot but it does make a noticeable difference in moi value.
Of course moi doesn’t have to be that high to make a yoyo spin long during regular play. The response area and how the shape is actually influences the spintime more than just a 5-10% increase in moi. I’ve had designs with way less moi spin longer than those with much higher moi thanks to them being designed with everything in mind.
Visualize yourself of the shape you’re making and how the string would rub along the side of the yoyo when you’re making it. The smaller the contact area, the less friction it will have against the string.
The prototypes I recently got has around 14-15k moi for each half, with 54.5mm diameter and 42.5mm width at 65.9g weight, and I think they spin for a remarkably long time. They’re not a super rimweighted design either since they were a capped design.
I bet you can get moi much higher with your current specs and same shape. It’s all about maximizing the amount of material you have with subtle design elements that would minimize the spinloss occurring from string rub.
1 Like
Try picking up a set of calipers and taking some measurements of yoyo’s and bearings in your collection. Really helps with the visualization and CAD process. Looks like you’ve taken a great first step and I’m excited to see what you come up with!
2 Likes
@BearingGoBRRR thank you for sharing your first design! Your bearing seat looks visually correct; the dimensions also look about right. However, I would add a bit pf space between the virtual “center line” of the yoyo and the bearing post; to give it clearance when it closes all the way.
This part of the design is very concerning to me! It is ultra sharp! For the outer corners I usually start with a pretty large radius; 1.5mm or so. Depending on design goals that could go up or down, but it’s a safe starting point that won’t get you in trouble by hurting your hand or cutting someone.
3 Likes