zermmerit tool

Welcome  They do make such a tool.  Though you might want to be specific about which pattern.  There were a lot of different ones.  Since you said stamp I'm guessing the waffle pattern??

they did it in finescale and the guys said he bought a stap it came with different patterns, guess i can try and make 1

This might be what you're looking for.  Some of these armor guys might know specifics.

http://www.squadron.com/ItemDetails.asp?item=ACC35003

If your doing a late tiger 1 AFV club makes one i actualy purchased one works pretty good alot easer than the the other ones ive seen. I used mine with milliput putty and it has to be paper thin and the suface needs to be roughed up to get it to stick.

Hers a picture it comes with 2 roller wide and thin

In addition to the AFV roller-type device (looks like a watch crown on an axle), Tamiya makes a nice set of Zimmerit tools (which are themselves photoetched).  My preference would be Gum Ka, which I believe is a Japanese company.  Frequently available on eBay, but also Japanese retailers like HobbyLink Japan and RainbowTen.  Their Zim tool is supposedly more accurately scaled and versatile than Tamiya's.  The company makes decent photoetch, and was the first company to produce engine screens for Dragon's 3 in 1 1/35 Initial Tiger I.  Good luck!