On screw holdfasts Richard wrote:

>So - positive side is you can crush bricks to powder if you want
>negative is the slow speed of setup - you need to adjust the
>screw .

And Jeff added:

>This, including the fiddly setting up, is also my experience.

I have never used forged holdfasts because I have never discovered a local
source, and there is a limit to how much postage I am prepared to pay to
ship lumps of cast steel across the world.  Subject to that limitation I am
a devotee of the screw arm holdfast, and snap them up whenever I see them
secondhand.  If you are thinking of venturing down this path, a few
observations.

Bought new they are extraordinarily expensive for what they are, at least
in Aus.  Secondhand they seem to come cheap, presumably because the person
selling has no idea what they have, or no longer have a bench to go under
them .

All of the ones I have seen here are English:  Woden, Record or Marples,
and given the incestuous relationships of the English manufacturers all
were probably were cast with the same set of patterns.

They come in at least 2 sizes (for simplicity's sake "larger" and
"smaller").  I say at least, because I have only come across 2 sizes so far.

In my experience, within the single size range any makers holdfast works in
any other makers collar.  But a "smaller" holdfast will not grab
satisfactorily in a "larger" collar, and it is physically impossible to get
a "larger" holdfast into a "smaller" collar.  So decide early on which size
you reckon you need and try to avoid mixing and matching in the one bench.
Oh: you only have one bench?

ALWAYS grab a collar if you find it in a box of junk.  Like clamps you can
never have too many collars, in fact more to the point, you will never have
enough of them.  If you find another holdfast lover these are more valuable
than gold as trading goods.

Having never known anything else, I don't find them fiddly to use, but then
for me time isn't money.  If I was earning a living on piecework rates I
can see the attraction of a whack to set, whack to loosen arrangement.

Screw holdfasts can be set one handed, and released with a fractional turn
of the screw.  However you will find that it always takes a fraction more
screw to tighten than you win in releasing it, and eventually you will need
to devote a few seconds to winding out the screw.  You can however save
time by doing this while you have stopped work to contemplate your latest
unforseen problem.  I seem to generate those faster than I use up the
travel in the screw  ;-)

I recess my collars, though I haven't covered them as Jeff suggests: a good
idea which I will follow up on.  In 30 years or so I don't think I have
dinged a cutting edge on one, though with so many other things to hit on my
usually less than tidy bench I can't be sure.........

Regards to all,

Tony B
Hobart, Tasmania