The most common and most likely answer to this crossword clue is the 6 letter word BOWSAW
I've seen this crossword clue in The Times
B
O
W
S
A
W
Buddy explains!

The straight part
We know that "Cutting tool" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case cutting tool = bowsaw.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.
What does BOWSAW mean?
BOWSAW noun- A lightweight metal-framed saw in the shape of a bow with a removable coarse wide blade, used for cutting tree trunks.
- A woodworking saw used for straight or curved cuts.