Dear Gerard,
It's possible, but not very.
Backspin from an iron shot really comes from a combination of lofted / angled face and smushing the ball against the tilted face. The bottom of the face hits the ball sooner and smushes the ball flatter than up top on the ball, and then the smushed ball rebounds bottom first. That's what makes the ball spin backwards (bottom forward and over the top going backwards). If the clubface smushed the ball evenly, there would be no rebound from the bottom and so no backspin. The function of backspin is to give a ball "lift" since the backspinning makes the pressure above the ball lighter than beneath, so the pressure differential pushes the ball skyward as it spins. That's why a really crunched pitching wedge seems to climb higher as it flies -- because it does, from the backspin.
In the case of a putter, there isn't very much "smushing" going on -- just a tiny bit. So there isn't much if any bottom-first rebound as the ball reshapes itself after being smushed. What you get instead is some launching of the ball up in the air from the loft of the face. There may be a minor amount of spin in the ball while it is in the air, but it will very soon disappear as the ball reconnects with the turf.
There is a little "sliding" of the ball up a tilted face, and the sliding friction can cause a little backspin, but not much at all. And again, it goes away very quickly as the turf gives the ball forward spin.
In the old days, there was a putt stroke that supposedly gave the ball "breaking" action. I gather it was something of a chopping down on the back top of the ball. If this gave the ball some backspin, it did so into the turf while moving the bottom of the ball forward. Punching the ball into the turf going forward is the quickest way possible to get rid of any backspin, so if the "breaking" stroke gave the ball a little backspin, it very quickly was washed out.
So, technically, yes -- a putter can give a ball backspin. But it seldom makes any difference at all.
Just for fun, you might want to try smacking a golf ball off a tee peg with your putter. You can often get about 150 yards out of a putter. But you won't get much backspin.
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Cheers!
Geoff Mangum
The PuttingZone
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