I’m designing a yoyo & I just want to know how much weight would be added on if I put in a size c bearing + an m4x10mm axle made of stainless steel & a pair of flow groove pads.
If you’re serious about making a yo-yo you shouldn’t rely on others to give you accurate weights/measurements.
10ball is 2.2 grams
flow groove pads are .45 grams/set
axle is .6 grams
I could be wrong, but may want to check with Shawn and David before designing (making) a yoyo that uses their Flow Groove pads, most likely there would be some licensing involved, and more importantly you wouldn’t want to step on peoples toes 
Post above yours is Shawn (The Machinist)!
db
Yeah, I know. He was just commenting about the weights though.
Get your own scale. I got mine for $10 something, 200 grams max with two decimals. It’s been reliable on me.