Damped Torsion Spring?

How big of a box? How heavy is the lid?

John

If it's relatively small, you can probably use a regular style hinge design lubed with "damping grease" and the torsion spring to make it "ooze" open. That's what's used in little things like calculator lids. I don't know how large an item the same stuff could be used for, but Nye could likely tell you.

The J.M. Nye company makes damping greases. I don't know how large an item the same stuff could be used for, but Nye could likely tell you.

This page describes a sample kit of these types of greases:

With the right approach, you might be able to "schnorr" enough from them as a free sample to do what you need to do.

Machinerys Handbook gives you formulas to make your own torsion springs from spring wire. Used it on my page here, although a bit larger scale:

Neat! Noted and logged!

I probably should have defined "schnorr" for those not familiar with that particular German/Yiddish expression:

In my college daze in the 50s a buddy and I got letterhead printed up bearing a realistic looking but non-specific company name. We used it to request free samples from parts manufacturers. Back in those days our hobby projects were mainly building vacuum tube "Hi Fi" equipment, which often included quite a few "schnorred" components.

Jeff

I meant the grease. :

Many Thanks to you Jeff. good info will pursue...

Steve