Underpins / Wedges - breaking when firing

[Jacko]

Hi all,
Any advice appreciated

On one of my underpinner machines, the wedges are snapping when they fire

12mm wedges, often breaking ( This is when firing with no wood in the clamps, just for testing )

Never seen this before, and we have had alfa, casesse, taurus underpinners over the years

Any suggestions what may be causing this
we have swapped out heads, and still getting the same issue

All advice appreciated

thanks
Jack

[Not your average framer]

I'm tending to think that this might be a problem which the under piner, rather than the wedges! Is the under pinners hammer blade and the wedge receiving block, which the hammer travels up through, looking intact as undamaged? Als, is it only 12mm wedges that are causing this problam? If so, this might be a good time to try a different make of 12mm wedges.

[prospero]

What make of machine?

I'd tend to think you need a new hammer as it's looks as though it's not getting a good contact
with the end of the v-nail and is going around the side.