bugbear

I have a dim memory that in engineering a distinction
is made between holding work such that it truly
cannot move (e.g. an object held in a bench vice cannot
rotate round a vertical axis, since the jaws are in the
way), and holding work only by friction
(e.g. an object in a vice can slide up and down,
if enough force is applied).

I *think* there are jargon terms for these
two notions.

Can anybody tell me what they are,
or (alternatively) wether I'm
misremembering badly?

BugBear

Tom

bugbear wrote:
> I have a dim memory that in engineering a distinction
> is made between holding work such that it truly
> cannot move (e.g. an object held in a bench vice cannot
> rotate round a vertical axis, since the jaws are in the
> way), and holding work only by friction
> (e.g. an object in a vice can slide up and down,
> if enough force is applied).
>
> I *think* there are jargon terms for these
> two notions.
>
> Can anybody tell me what they are,
> or (alternatively) wether I'm
> misremembering badly?
>
> BugBear
>
You did say jargon?

Purfeck and Prayer respectively? :-)

Tom