Science Toy III (Sit and Spin help needed)

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Science Toy III (Sit and Spin help needed)I made this sit and spin years ago. A sit and spin is something a kid sits on and is spun around. It helps teach about angular momentum, acceleration and inertia. Plus it is hell of a lot of fun. As you can see it is a hub from a car. I think it is the rear axel from a front wheel drive minivan. A teacher wants me to make them one. What would you use as an alternative to using a car hub? I’m not sure what type of bearing set up you would call this. I have lost my auto-recycler connection so I am looking for alternatives.Thanks Reber Attached Images
Reply:What about this..Sorry about the crappy drawing..It's alot better than my attempt at computer drawing..Based in my drum seat..Or just go out and get a drum seat..I can go round and round on mine untill  and i'm ready to puke.....zap!I am not completely insane..Some parts are missing Professional Driver on a closed course....Do not attempt.Just because I'm a  dumbass don't mean that you can be too.So DON'T try any of this **** l do at home.
Reply:Any Timken (taper roller bearing) setup would be best to handle side loads.  Although, any bearing would probably work for what  little use it will get.  That's what auto spindles use.  Check a Harbor Freight catalog for cheap ones in the trailer section.Hobart 140 Handler w/ gasHyperTherm Powermax 380 Plasmaoxy/acetylene
Reply:Or JC whitney.
Reply:Cool thanksI never thought about trailer stuff or a drum seat. I'm so ignorant sometimes I can not think outside the box.
Reply:Old vw golfs and jettas used a bolted on rear axle that would do that set up. A junkyard trip may be due, lol. Examples like these.http://www.germanautoparts.com/Volks...Drivetrain/200
Reply:Along the lines of Zaps drawing.  TSC sells large diameter  pins and sleeves.
Reply:I will look into that. It has to spin easy (low friction) Once I asked for volunteers and a kid sat on it I gave him a spin. When I stopped after a few good rotations he truly looked GREEN. I asked if he was OK, he could not speak at that point. I carried him outside he pucked in the grass. He told me later "I always puck when I spin on stuff" I asked him why he volunteered he said "i did not know it spun in circles" Lucky I'm a friend of the family his mom said "my son is a dumb as sometime"
Reply:Why not use the plate and ball bearing lazy susan? I saw them in a catalog - I forget which one - that had 200-300lbs rating. Or you could use the same ones for chairs and bar stoolsFire!, Fire! Oh wait, that's my torch...Lincoln PT-225 TIGLincoln 175 MIG
Reply:Wal-Mart used to sell what your looking for, Boat seat mounting plate with 360deg. ball bearing action. Four bolt system for mounting. And not to costly best I remember, under 20.00 each.Miller Thunderbolt 225Millermatic 130 XPLincoln HD 100 Forney C-5bt Arc welderPlasma Cutter Gianteach Cut40ACent Machinery Bandsaw Cent Machinery 16Speed Drill PressChicago Electric 130amp tig/90 ArcHobart 190 Mig spoolgun ready
Reply:In my Engineering Physics class in college the professor just had a stool with a top that would turn.  It doesn't really take that much to demonstrate this stuff.
Reply:Any old office chair that spins will do. Ones with castors reduce the chance of breaking the chair through excess force, but mean you need more space (or spare students in case you break one).
Reply:See next post.Last edited by Weldordie; 03-01-2008 at 04:11 AM.
Reply:As I recall, the original Sit-N-Spin had a central hub with a mushroom top attached to the base with a rotating platform that the kids would sit on.  By sitting on the platform with a leg on each side of the hub a kid would spin by applying torque to the mushroom top.  Is that what you are building?It was not just a big Lazy Susan.Last edited by Weldordie; 03-01-2008 at 04:09 AM.