3700 rpm is a bit too fast for cutting steel. It should be 2000 to about 2800 rpm. Saws intended for cutting wood go to fast for metal cutting. I know nothing about the Evolution saw that you are talking about, but Evolution does make metal cutting saws, as does DeWalt, Milwaukee, and Makita. All of these run slower than wood cutting saws. For bar stock and tubes it would be best to get a dry cut metal cutting chop saw, kind of like a miter saw, but designed for cutting metal. These are not the abrasive saws, but low speed versions of miter saws that use the special metal cutting blades. The advantage to these is that both the saw and the work is held in position during the cut, making a straight cut with no blade binding.
Our first metal saw was the Milwaukee 8" metal cutting circular saw and we initially tried using it for everything including round and bar stock. It cut them OK, but we found that using this saw free hand without any kind of guide caused very short blade life, and blades for metal cutting aren't cheap. For metal cutting the saw needs to be guided so the blade doesn't bind in the cut. When the blade binds, teeth are chipped and broken easily. You also don't want to stop in the middle of a cut. When you do the steel develops a hard spot at the stop point and it will chip teeth when you resume the cut.
We now do almost all metal cutting with dry cut saws (we've added a few more than listed below) and hardly ever light up a torch for doing small work. Fit-ups are better, piece cutting is faster, and you can pick up the pieces with your bare hands immediately after the cut is complete, something that can't be done with any other metal cutting process.
Get the right saw for the job. You will save money in the long run.
Last edited by CharleyL; 05-13-2012 at 10:14 AM.
Miller MM 252
Miller DialArc HF TIG / DIY Cooler
2 Victor Torch Sets
2 Miller Digital Elite helmets
3 misc. helmets
Dry Cut Chop Saw
Dry Cut Circular Saw
4-4 1/2" Grinders
5 Ton Wallace Gantry
Misc. benders, etc.
Lots of tools