15 Dec
2014
15 Dec
'14
1:19 p.m.
In my experience, Greenlee is the industrial standard for metal punches. As
duly noted, they are not cheap but of excellent quality - and will last a
typical user's lifetime.
As for the Quick-Draw device, if you think about it, I really cannot
increase the maximum force / material thickness that the punch can work.
Whether the punch is driven manually or automatically, the weakest link in
the chain is the same - the tensile strength of the threaded portion of the
drawbolt.
However, it would reduce one of the major wear points, which is the
threaded connection between the die & drawbolt. With the hydraulic device,
you no longer need to drive the thread to develop the pulling force - the
hydraulic piston develops that force for you, so no need to drive the
thread. But in my experience, I suspect that the cutting edges of the die
would dull before threadwear became a point of concern.
If you want to speed-up the operation, drive the punch through with an
impact wrench once you've got it properly started.
On Mon, Dec 15, 2014 at 1:52 PM, tony duell <ard at p850ug1.demon.co.uk> wrote:
I don't know about the hydraulic part, but
I've had really like my
Greenlee
punches.
That is the sort of thing I've read elsewhere. Greenlee are not cheap, but
they
do the job and last. The brand we used to use in the UK was Q-max [1] but
they don't do the sizes I need
[1] Again a good brand IMHO. I convinced my father to buy me the 5/8", 3/4"
and 1+1/8" ones about 35 years ago. I am still using them. Of course those
are
the sizes for B7G, B9A and Octal valveholders... I think the company
started out
making RF (and IF?) coils, hence the name.
The ones I am looking at are the conventional 'tighten the bolt' ones
albeit with
a thrust type ball race on the bolt to reduce the torque needed. The
published
specs exceed what I need to do (they are specified to punch 1.6mm mild
steel,
the thickest I want to do is 1.2mm).
The hydraulic thingy seems to fit in place of the nut and pulls the punch
bolt
through the metal into the die. Nowhere can I find info on what advantage
it
gives. If it's just quicker then I am not going to get one.
-tony