Just for info,
I went to SIM LIM SQ few days ago and hope to get my old 3G mini SIM cut to nano SIM.
But the shop staff which offer paid cut service told me that the SIM card is old one and it cannot be done due to the die size of the old sim card.
See similiar Picture:
Back home, I want to cut the SIM card by myself ( use scissors)before heading to Singtel shop. I looked at the following URL about the nano SIM cut.
Convert Micro SIM To Nano Simi Phone 5 : Geek Super
As per the guide, the old SIM card need to cut the entire forth row which parts of the SIM die occupied. so that the remain three row will be aligned with the contact points at the middle.
What I did is, I moved the cut line down about 0.8 MM, so that actual cut will not damage the die and the three contact points were still able to connect to the first three rows.
Finally I succeed, the old SIM card now is used on my Iphone5 without any problem.