The most dangerous and wonderful tool - Knife rather Blade!!

Sir

Recently I was again buying bunch of tools such as Wire strippers, Callipers, Cutting mat etc. for my household electronic lab. But today few hours ago mine VERY VERY OLD Blade broke & also I didn't know which one is it.

That's why I need your suggestions about what blade I should buy. Also I want to tell you that I use my blade to cut hard cardboard, soft cardboard, Sun board / foam board for the body of my projects as I do not have good access to 3D printers.

Thanks & Regards
PSK

A Stanley Knife (model 99E) ?

For fine work a scalpel with blade 10, for very fine work blade 15.

Get a knifewrench, as used in hospitals :wink:

Sir

I would like to have pen knife rather than thermocol cutter like knife.

Depending on the balance of cutting capability to control that you need, look at “box cutters” (those various types of knives with either reversable trapazoidal blades, or long breakaway blades; the former allows you to apply more force, and generally provide a more solid link between you and the blade, the latter is cheaper, and lets you break away the blade in sections as the section you’re using gets dull), or x-acto knives. I often use bare safety razors, since you can get very fine control over the blade since you’re holding it directly - but other people often get scared for my safety when they see me using them like that.

Small knives like this are generally cheap, so you don’t have to pick one kind for all tasks. Better to have a selection so you can choose the right level of strength vs precision.