Spring for hanging baby basket?

We have a newborn in the house and I hung a wicker baby basket from the ceiling so it could swing. Then I found a coil spring which I added to the system, and the up-and-down motion comforts the baby much more than swinging alone. Only thing is that the spring oscillates a bit too fast, and not very far or long. I think I'm looking for a slightly less stiff spring with more coiled length, but where to find one? I can't think of any typical application where a spring like this would be used. The basket + baby weighs about 10kg, if that helps. Thanks,

Whatever you end up with, install a safety line in case the spring breaks.

robobass Inscribed thus:

Try a rubber bungee cord !

Oh, I dunno about that - get it right, you could fire the kid through the ceiling..........(yeh, poor taste, I know)

Andrew VK3BFA.

How about a fishing scale?

How about a fishing scale?

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Then you could also tell if the nappy was full.......

When my youngest was a baby (he turns six next month) we had one of those: a spring mounted hammock for the baby to sleep in. It worked great. We had a rope run through the spring to catch it if the spring broke. Then he outgrew it and we gave the whole thing away.

Except the hook in the ceiling. We left that there.

Fast forward about four years. The oldest kid, now about to turn about 19, wanted a punching bag, so we got the smallest one that Everlast makes and hung it from a chain from that hook. Lasted about a month before the hook pulled out of the ceiling. Granted a bodybag weighs a lot more than the baby did, but it was underving. We couldn't see how the hook was attached before it pulled out, but it was right at the edge of the wood.

Moral: put something soft underneath, too.

Elijah

------ ps, anyone want a punching bag?

Enough with the safety tips already! The thing only hangs two feet off the floor anyway so the toddler can swing it and watch the new baby. The screen door spring sounds like a possibility. Any engineers out there who can quote me some more precise numbers, like load/deflection/ rate etc? I'm looking through McMaster and getting a clue, but still pretty dim on this. They do sell the exact thing I want here where I live in Germany, but they can cost upwards of $100 new. I ain't one of those types who pays a hundred bucks for a three dollar spring.

The relevant equations you need are: F=-kx and f=1/2pi*sqrt(k/m) where F is the displacement force k is the spring constant x is the displacement distance m is the mass of the baby f is the oscillation frequency (all units in meters/kilograms/seconds)

To slow the oscillation freq you need to either increase m or decrease k. To decrease k use a weaker spring or use 2 or more springs in series. The gotcha is that doing this will increase x so you'll need more room for the total stretch. To increase m put a bowling ball in with baby. Art

That sounds like a lot of work. Say you just wanted to launch a 20-lb. baby, oh, say, 200 feet with optimum ballistics?

I'd probably opt for a trebuchet and just play with it till I got it right. Art

Art, Thanks, That's what I was looking for. I bet I can find just the thing I need at McMC for less than the cost of shipping!

Just off the top of my head, it seems to me that a screen-door spring would be too stiff, i.e., with a weight I can envision for a baby in a wicker basket, a screen-door spring wouldn't extend at all. You'd have to add some ballast to strech the spring out enough to mane it bouncy; but you can just go down and pick up a screen-door spring for lessee... ... Well, I'll be dipped!!!

Speaking of springs, I remember seeing a physics demonstration of a thing hanging on a spring, and the trick was they picked the spring such that the period of the rotational moment was the same as the period of the spring moment, (twirling vs. bobbing); and the motion traded off from twirling to bobbing and back and so on. I have no idea how to adjust either, other than changing the rotational inertia of the basket with weights. ;-)

Good Luck! Rich

Wilberforce Pendulum

This will lead to a very confused child.

Joe Gwinn

No, Joe, it'll turn out gymnasts!

-- The more passions and desires one has, the more ways one has of being happy. -- Charlotte-Catherine

Arial ballerina?

Joe Gwinn

Huh? I didn't know fonts danced. Oh, you meant "aerial", dincha?

-- The more passions and desires one has, the more ways one has of being happy. -- Charlotte-Catherine

You need an aerial hammock.