Tradesman vise is O.K. for some stuff. It won't open real wide and it will
have a little wobble in it. Get the machinist vise. You'll have way more
pride in your work, the thing grips like vise grips, and it'll last forever.
I've put cheater pipes on the handles and bent them around and the thing
still keeps on working. Best investment you can make. Check some of the
surplus machinery dealers out. They usually have them fairly reasonable.
Bought my last one for 50 bucks at the flea market, someone had painted it
with green house paint and it looked like crap. Cleaned up good as new. I've
seen ENCO sell 4" machinist for $250.

6" Tradesman is to loose and won't open wide enough.