Dear AZ:

You wrote:
> He went away not to come back for three years.
> He put the gun away not to touch it again.
> He put it away never to touch it again.
>
> Are the above sentences correct?
> Do they mean:
> 1. his intention was not to come back for three years/not to touch it
> again (regardless of what really happened)
> or do they mean
> 2. that was just what happened (regardless of whether he intended it or
> not).
>
Normally they would mean “that was just what happened,” though the second one could be construed the other way in some contexts.

If you want to say the second sense, you would put the adverb before the verb: “He went away to not come back for three years.” [By the way, that first sentence is a bit awkward]. “He put the gun away to not touch it again.” “He put the gun away to never touch it again” [this is fairly common].

With the infinitive directly following the action then you have the infinitive phrase meaning “in order to.” To make it clearer, you might want to use the phrase “in order to,” especially in the first two sentences, if that is what you mean. “He put the gun away in order to never touch it again” or “He put the gun away so that he would never touch it again.”

Keep in mind that English does not use verbal phrases as much as many other languages. English speakers are more likely to use subordinate clauses.