Has any one ever used living hinges for fine mechanisms?

[paboar]

I am designing a medical measuring instrument and I thought that I could reduce tolerances by using living hinges in its mechanism. This mechanism must be able to move from 1-15mm with steps of 1mm in between. But I am not so sure how accurate it would be. Has anyone ever used living hinges for fine mechanisms, or has some tips on the use of living hinges?

 

[btrueblood]

Well, if you mean plastic (polyethylene) living hinges, no.

But flexures, made from suitable thin spring-steel strip, yes. At least a couple of times, we replaced a hinged joint with some flexures made from steel pallet banding. A company called C-flex, I think, makes a line of these too, in high-precision interchangeable parts.

 

[sreid]

I have used plastic flexures a couple of times. Flexures can have very high precision. I have no idea about accuracy if you get out of the elastic reagon.