Automatic Self-Inking Number Stamp

I acquired an automatic self-inking numbering stamp this weekend thanks to the in-laws. It’s a Uchida DN-7, with 6 digits and a choice of automatic increments.

Excitingly, this stamp is broken. Fully-functioning, it would have been reasonably good fun, but broken; well, there’s hours of entertainment in that…

Having worked as a print finisher, and having personally broken one of these things, I feel qualified to tell you about them. Numbering stamps can be used by hand or mounted in a larger set-up and if the machine is set wrong, the stamp gets exposed to too much pressure as it pounds the paper, eventually cracking.

So, that’s my diagnosis based on the evidence, and I think it’s probably beyond my abilities to fix it. I reckon what I need to do is straighten out the cracked part and secure it either with a riveted or glued strip. Neither of these of course are strong enough for machine-use, but I think it’d hold for manual stamping if I used it gently.

With my very limited metalwork skills I’d say my chances of success are slim. Most probably I’ll take it apart wrong and a load of spring-loaded wheels will ricochet across our kitchen.