Should I cut 3w shaft length to match 7w?

Just started playing golf last summer so I'm not very good.

Top of my bag is driver, 16 degree 3w, and 21 degree 7w.

I'm really inconsistent when hitting my 3w. Should I cut the shaft length 1 inch to match my 7w? I'm thinking that if I can duplicate the exact swing for both of my fairway woods then I will decrease the frequency of poor strikes with my 3w.