How can you make a makers mark on Kydex

[sonil]

hey guys i was looking at some sheaths and i noticed some guys make a makers mark on the Kydex ..what did you guys use?

 

[Dinges]

http://www.youtube.com/watch?v=qVtD537JMgw

Vid is not mine, hope it helps.

 

[rayban]

I have a flat plate made of magnesium that I use on leather ...I use a one-ton arbor press to make the impression....just wondering if that would be a better way rather than to strike a stamp.....no hump on the back side (?)