It is not not made by hand
There are two "not"s here. Is this sentence right? If yes, what kind of sentence is it?
More example in [corpus][1]
[1]: http://corpus2.byu.edu/glowbe/ ,and you type"not not" in it, you can find there are lots of examples here.
Best Answer
This is a great question, and really interesting! To expand a bit on what Maulik V says (which I agree with), I think this could have a few different meanings, depending on context/emphasis:
What all three of these cases have in common is that they all follow on from (or respond to) an idea or statement that the thing is (or is not) made by hand. To try and make this clear, I'll give some examples.
1, 2: 'Made by hand' might imply that something is 100% made by hand, with no help from machines (a very narrow category). Or, it could mean anything which is made with some use of hands - e.g. someone uses their hands to make some of it, or to operate a machine to make it (a broader category).
When two people talk about this, they may use double negation to show that there is ambiguity, a difference in definitions, or that it is not as simple as 'yes'/'no'. In both of these cases, the second not would be verbally stressed.
Imagine Bob is admiring Alice's shirt (which is fabulous)...
Bob would likely stress the second 'not' very clearly, and the interpretation would be either:
It could easily be a mixture of the two. Another example of where 1 or 2 might apply:
3: The matter could also be a simple disagreement with what someone said, putting 'not' in front of a quote of their statement ("not made by hand"):
Here, there is no significant stress on the second not - maybe a light stress on 'not' and/or 'not made by hand'.