My hand-turned poplar yo-yo!


#1

Pictures are at the bottom. Thought it was walnut then discovered it was poplar after I cut and started shaping it. So it is incredibly light. Way too light (34g!!!). About 36.5mm wide, 60mm diameter, 1/4" walnut axle. Better luck next time with a known wood.

It also has an intense, visible, and pulsating vibe, though it looks pretty decent rolling across the table. Going to try some calipers all around to see if anything is off. Trying to attribute it to one of the following for next time:

  1. Hole centering: I marked a circle while it was on the screw chuck I made and tried to hit the center of the circle with a regular bit (7/32" bit). Got a brad point bit for better accuracy next time and I don’t plan on drilling the hole all the way through for the chuck so I can mark the center better as well.

  2. Drill press angle: I don’t know how to tell if the platform is a true 90 degrees: This is my father-in-law’s drill press and it is very, very old. Many decades. Likely this?

  3. Assembly: I ever-so-slightly shaved the edges of the walnut axle and just gently tapped it in with hammer. 1/4" dowel into a 7/32" hole, no glue. I assumed the 16.5 mm hole in each half would be plenty to straighten it out. Was this a bad assumption?

  4. Wood expansion: This stuff has been around for a while. I thought it would have been seasoned.

Any other ideas? What is likely? Pictures below (and the screw chuck with the poplar block on it).


#2

Looks nice. You talk about possible drill press issues but the piece looks to be mounted in a lathe. And I agree, poplar is one of the lightest woods around. Sounds like you have analyzed what could have gone wrong fairly well.


#3

Looks good.  You could use a jacobs chuck on the lathe for a center hole if you have one.

From what I remember reading on smoothness for a wooden yoyo is that it is better to have each half weigh the same as be exactly the same size.  Of course I would make the rim’s the same size then take some off the side of the heavy one.

If you really wanted to go for smoothness, you might benefit from balancing each half too?  You could buy or build a prop balancer for this.
http://aeroquad.com/entry.php?129-Prop-Balancer-Built
Basically attach to the balancer and spin.  Mark any heavy point and remove some wood or weight the lighter part.


#4

I use a router jig for my yoyo halves so each halve is identical each time. Poplar is not a very dense wood (and it’s rather soft), and I like light yoyos for kick flip type tricks, but cherry is the lightest I’ll go. Also, I would narrow the the profile. The wider the yoyo, the more precise each halve must be because the differences in the density of the two halves will be that much more exaggerated. You can make smooth wide wooden yoyos, but expert precision in a the shaping must be executed; also, cutting into the sides to create cups will help distribute the weight. Remember though, wide yoyos with a fixed wooden axle have a greater chance snapping when you try to shove it in your pocket.
Another tip for you would be to match and balance the yoyo halves before gluing in the axle. Rotate each half and make a test throw after each adjustment to find the smoothest orientation; you can then mark them with a pencil.
Wood is an organic medium, so even if two halves are visually identical, they can still have different weights and densities, which is why matching and balancing the halves is so important. Also, most often (but not always) matching the direction of the wood grain on each halve will eliminate a lot of vibe.
I hope this helps;)


#5

Great advice everyone, thanks. I thought the screw chuck would be a good poor man’s method of getting the thing mounted for shaping. I can’t do the center hole on the lathe with this method because there’s a screw where the hole goes. Thus I have to make the final hole after shaping and marking the center on the lathe. I plan on marking the center and drilling more precisely next time.

Paul, your OUT video was really inspiring. The router jig looks amazing for cranking out halves. Do you match them by weight? I didn’t think the weight of each half mattered that much. Aligning the grain seemed to help some.

That prop balancer idea is cool for balancing. Is that the way to go?

I have some maple and purpleheart for next time so I will probably go smaller and slimmer. I made it big and wide because I thought it was walnut!

Also I think I took the halves on and off the screw chuck while doing some of the work. That was probably unwise if I wanted the halves to be precise.


#6

After you turn the halves you could use a jam chuck to then drill the center hole on the lathe with a jacobs chuck or similar.

I’m not sure on the prop balancer and yoyo havles but I know it works wonders on props, especially speed planes. ;D

I know on bowls I’ve noticed misalignment if I took them off a screw chuck or got a bad catch so that might be an issue?

Good luck!


(rizkiyoist) #7

This is my personal method of removing vibe on a wooden yoyo.
Try this on the less valuable yoyos first. Throw the yoyo to sleep, then quickly take a pencil and mark around the rims while it’s spinning. The side with the pencil mark will be the one that ‘protrudes’ while spinning, sand this part until you can’t see the marks anymore. Test and re-do if necessary. Even better try sanding some of the sides where the pencil mark goes too, preventing flat spot and basically keeping the shape round. If done correctly you’ll barely able to tell that it’s not perfectly round. Don’t expect it to be plastic level smooth though it will be a lot better than before.
This has fixed about 90% of my custom yoyos I let someone else turn for me.


#8

Thanks for the advice! I’m looking forward to using a harder wood. What are those darker ones?


(rizkiyoist) #9

These are Teak, basically don’t work because the weight variance is simply the worst for yoyos. However I had good result with Mahogany (the brighter ones), though it’s lighter.


#10

Well it looks cool at least. I would think you would also have better luck with lumber milled with the grain for better balance.