A short video of Impact Engraving on hard anodized aluminium.

                                    http://www.cooperman.talktalk.net/impact5.wmv

Because Sam made such a lovely job of producing this Wile E Coyote I just had to do it. http://www.machsupport.com/forum/index.php/topic,12140.0.html

The federate was initially set a little too fast for my impact tool, which uses the mains frequency (only 50 Hz here in the UK) for it’s pulsing and I got some variations in line width on my first attempt. Reducing the federate seems to cure the problem but you can still engrave pretty quick with these little tools - they do, however, make a fearsome amount of noise !.
The impact tool used is a Burgess handheld device for which I have made a small clamp to hold it to the Z axis. It is switched on/off using the spindle relay.

Tweakie.

Awesome! It's nice to see the coyote being used, too. So lets see.......you've done a router, a knife, a laser, and now this. What next??? Super kitty sure does have a bag full of tricks.

Very cool tweakie, so how did you go about setting it up on the material?

What sort of "movement" are we talking about, does the point go in and out on the impact engraver does it oscillate?

I have a vibration pencil for engraving, is this the same idea?

Thanks for sharing- 
Dave

Sam - "Stay tuned folks" I have a cool idea in the pipe.

Dave - Exactly the same oscillating movement as your pencil. My movement is adjustable and was set at about 0.5mm with zero Z about 0.2mm above the work but there is a certain amount of overshoot so the retract height has to allow for this or the work is spoiled during the G0 positioning moves.
The finished work is not as neat as with conventional, rotary engraving but I think it's main advantage would be with hard materials such as SS.

Tweakie.

Sorry Dave, forgot to attach the pictures (senior moment).

Tweakie.

Agreed, it would be great for hardened materials, thanks for the info - great job.

Dave