Jack V wrote:I think you should look up Otoscope first they are very cheap . Once you have one they are also very handy for many other uses .
It is a fair enough way to do it but you must also be right about the first few bad cases you find in the batch which needs inspection skills . Then after a while you get to know how many firings they will last before you toss them . Brands do vary in life expectancy . Don't discount a new idea just because one person ridicules it in another thread . You could be missing out on a good thing . The knockers don't want you to be any better than they are it scares them.
As a tradesman who often needs to inspect machinery, condensor, boiler tubes and pressure vessels I have tools ranging from a basic otoscope right up to the digital recording scope for quoting.
I have used the basic one on a couple of cases but it takes so much longer than a piece of wire and the wire is just as effective(probably more tbh), you will miss more optically, fingers are far better guages than eyes, weak spots aren't easily recognised in the early stages where they are by wire..
You have stated your opinion, I have stated mine. I am no stranger to their use but still use a simple piece of wire. Draw your own conclusions but you will never get cheaper than a piece of bent wire.
I could use abusive language as you have but prefer to simply state the facts. Let the OP decide.