On Thursday, 30 April 2020 14:56:33 UTC+1, Dave Plowman (News) wrote:
In article ,
tabbypurr wrote:
On Thursday, 30 April 2020 11:37:57 UTC+1, Dave Plowman (News) wrote:
In article ,
tabbypurr wrote:

Interesting. Last time I used those, long ago, they severely
distorted the sheet they were punching. Is there some way to avoid
that?

Get some decent quality ones? If the tolerances are poor, it won't
shear accurately.

The ones I was using were the Qmax you recommended.

What were you cutting?

boxes, mainly sheet ali. IIRC they were fine in plastic.

I've made loads and loads of holes with them in
various materials and not had a problem with distortion. Assuming you took
care using them, as it would obviously be possible to bend sheet steel by
the action of turning them with a spanner, etc.

With the metal in free air it's not going to see problematic torque.


In thin sheet, where it
matters, I tend to use a T handle driver.