Thanks so much for being here @da5id!
As you have mentioned in another thread - Side Effects were such an impressive discovery in modern yo-yo. I’m very curious about the development of them… How did it happen? Whose original idea? Was there an ‘Aha’ moment or more of a development over time? And are there earlier iterations of the design or did you knock it out of the park on the first try?
I 
Side Effects.
andre over here trying to win his own stock lol
LOL - genuinely curious.
I wonder if theyll produce new Side Effects
Andre,
Thanks for having me!
From the moment we first saw a tapped axle yoyo, we thought it could be done better. This stems from Shawn’s experience in machining and manufacturing. That and the fact that we only had a mill (not a lathe) was what led to our first yoyo (the Project) having a nut capture system. This was the first idea we had for doing a non-tapped axle system.
Down the road, out of frustration that anodizers were messing up our bearing posts, we thought that perhaps we could put the bearing post on a nut and in a sense “de-couple” it from the yoyo and that way, anodizing wouldn’t affect the size of the bearing post (bearing post is the most critical tolerance on a yoyo). We did this idea on later edition Y-Factors and Dingos (I think).
The key for Side Effects was an inspiration Shawn took from a physics principle that is used in machines. It’s called “Morse Taper” or “Taper Lock”. It’s used to hold the tools in place on our mill and on our drill press. It’s kind of like magic. If two pieces of metal are joined together with just the right taper angle then friction takes over and they “stick” together. The “stick” can be undown with just a little force and nothing really wears out. The other advantage to this is it perfectly centers things. Kind of like dropping a basketball into a trashcan - it will eventually bottom out perfectly centered.
The nut we used on the Y-Factor and Dingo had to pressed in. This made it permanent and also introduced some error (not perfectly centered).
Shawn’s idea was to use taper friction to hold a nut in place rather than doing a press fit (if the nut is lose, you won’t be able to assemble the yoyo - the halves just keep rotating.) It’s a brilliant idea, inspired by our work environment, and it turns out to work perfectly. He built a little proof of concept which worked and then we made the 54 with Side Effects and it worked!
I think this is the thing we will be most remembered for in yoyos. Not sure how Shawn would describe it, but I think this is the kind of idea that someone has a few times in their life. Shawn is a genius in my opinion.
I’m glad you dig them 
Amazing question and answer! 
Now please to be releasing more Side Effect compatible yo-yos 
At least two more coming this year …
This is awesome.
Lol 
