Yo-yo science experiment challenge: how much does your string stretch in play?


(Justin Thompson) #44

I did just acquire some premium nylons…


(Justin Thompson) #45

Ok I’ll do a stretch test comparing Airetic and some custom wooly nylons. Will begin when I arrive home from work, long as I beat the wife and kids home. #DadLife


(Alexander) #46

I’m in my last day of testing. If I’m not too late, I’d will try to post my results this afternoon.


(Mk1 Yoyos) #47

This science takes a lot of work! Should have some nicely worn strings in about a day.


({John15}) #48

@codinghorror maybe if you pre stretched nylon strings, you could tolerate them better? Just a thought.


(Mk1 Yoyos) #49

That’s why I’m including two pre-stretched strings in my experiment. These aren’t very bouncy to begin with, but I’m surprised at how far they stretched!


#50

Unlikely as the tendency to coil up so tightly is bothering me the most about them longer term.


(Alexander) #51

Experiment Stretchy String:

Purpose: To determine how long (if at all) a yo-yo string will stretch while used for three days.

Hypothesis: The string will indeed stretch due to play, about an inch or two.

Supplies: Two identical YoYoExpert 100% Polyester string (my go-to choice)
two tape measures (the first one I found was terrible. I happened to find a better one today); a camera (hooray for iPhones!); and one yoyo (the YoYoFactory Marco.

Procedure:

Day One: I choose two identical, YoYoExpert 100% polyester strings and lay them side by side. I then took a (see “Image #1” in Data/Results)


(Alexander) #52

Experiment Stretchy String:

Purpose:
To determine how long (if at all) a yo-yo string will stretch when used for three days.

Hypothesis:
The string will indeed stretch due to play, about an inch or two.

Supplies:
Two identical YoYoExpert 100% Polyester string (my go-to choice)
Two tape measures (the first one I found was terrible. I happened to find a better one today)
One camera (hooray for iPhones!)
One yoyo (the YoYoFactory Marco.

Procedure:

Day One: I laid the two identical strings side by side along a tape measurer. I then took a photo in order to compare to the end result(see “Image #1” and “Image #2” in Data/Results ).

Note that the loops were placed at the one inch mark. This is due to the fact that in order to use measuring tools most efficiently, you cannot assume that the length from the edge of the device to the one-inch mark is truly one inch (because the edge might have been chipped, broken, or bent, the metal clip could’ve been loosened, etc.). I took note that one inch would be subtracted from the length of the string.

I then took one of the strings and stored it away, not touching it until the end of the experiment. I then took the second string and attached it to the Marco and proceeded to play vigorously with it every chance I had.

Day Two: I repeated the last step of Day One, playing with the Marco.

Day Three: By the end of Day Three, I had again played with the Marco, and I moved on to the final step of the experiment: compare the string that had been played with to the string that hadn’t been played with.
I took a picture of the two strings as they lay side by side against the tape measurer (see “Image #3” in Data/Results).

Data/Results:
The two strings before play were both 47 inches long.

Image #1:

Image #2:

After day three, the played string measured 49.4 inches long. The un-played string had remained 47 inches long.

Image #3:

End result: the string stretched 2.4 inches whilst being played.

Conclusion:
This experiment showed that strings do indeed stretch in play. It was interesting to note that the un-played string was thicker than the played string, indicating that as the string stretched, it lost it’s thickness and changed in it’s feel.

I had an interesting thought while performing this wonderful experiment: does the string ever stop stretching? I guess the only way for us to find out is for @codinghorror to host another contest…

This experiment was fun for me to perform, and it showed me that even a skill toy can be used to teach a lesson and broaden our understanding of the world if we let it.


#53

Preform?


(Alexander) #54

Oops. Missed that…:grimacing:


(Mk1 Yoyos) #55

A: Elongated 3.4% in play only
B (prestretched): Elongated 3.3% during prestretching and 0% during play
C (control): Didn’t change
D (prestretched control): Elongated 3.4% during prestretching

Again, these are only 1/3 nylon. The full nylons I make take too long to stretch/break in for such a short time period.


#56

So from these results, prestretching is the same elogation as a full day of play? May I ask how exactly you prestretch? Do you put the string on the yo-yo and pull?

Wow that’s nuts. How long does nylon take to break in / stretch? Weeks? Months?

PM me for your science shutter :wink:


(Mk1 Yoyos) #57

The two strings I played each got about 1.5 days of solid play. That’s maybe 3-4 hours each - more than enough to play out a bulk string to exhaustion.

I stretched them right there on the board they were hanging on, a really hard pull for ~4 seconds.

For the Woolly Nylon strings I had been making previously, maybe a week or two before the ridiculous bounciness starts going away.


#58

Let me know if your science is complete, I got one last science shutter…


(Justin Thompson) #59

As much as I wanted to contribute and earn myself a Shutter, alas it was not meant to be. I arrived at work immediately after posting my plans to start my experiment, to learn that BOTH of my asst meat cutters had quit, through text, on the same day. I’ve literally clocked 38 hours since Thursday morning, and am still at work as Im writing this. And, since I’m now a one man meat market, I’ll be here 7 days a week until I can hire a replacement. I’m trying to be positive about it and focus on the extra income though, and stay positive. Sorry for falling through on my statement, but at least you know why now.


#60

No worries I can keep this Science Shutter around just in case!


(Justin Thompson) #61

Thank you for holding it, Ill see what I can do in my evenings, cuz I been missing out on ALOT of throwing haha. I’ll update you soon as I have enough empirical data to be deemed sufficient. You da man Jeff


#62

you still got some science shutters? im interested in doing this.


#63

Sadly I am all out, should have jumped on it sooner!

HOWEVER I do have other yo-yos… who knows what you might get? I’ll let you be the last entrant, show me some science!