Shears leaving marks under the metal

Hi there! I have a quick question re shears - I use mine a lot
(probablytoo often given the thickness of the sheet that I am trying
to cut, instead of a hand saw) and have noticed that my better pair
seems to leave a mark (a line/groove) parallel to the cut line. Are
they in need of sharpening? Or is it the nature of this type of
tool? When I use a saw to cut strips of sheet, at some point I stall,
fingers in my non-dominant hand spasm painfully, AND I usually break
the saw blade! I am hopingthat there are better solutions? Would a
guillotine cutter be a good option for straight lines? Or, is there
a way to secure the sheet/object, other than using my non-dominant
hand, to avoid trigger fingers from holding/stabilizing the sheet?

Many thanks! Ros

Not sure about the problem with you shears, I don’t have this
problem with mine.

As to the saw cuts, I can think of two things that may be happening.

  1. You may be holding the sheet too hard, and this can cause
    cramping, and 2) Your bench pin may be too low.

I found the above two reasons were causing my hands to cramp up, and
numbing the tips of the fingers gripping the sheet.

The solutions are fairly simple, don’t grip so hard, and either
raise your pin or lower your seat.

Regards Charles A.