I'm doing a job that requires quite a lot of mitre cutting and my choices for doing this are limited to a 14" Makita Abrasive saw and an old 9x11 Wellsaw. I chose the Wellsaw but spent quite a lot of time tuning it up to get good cuts.
It occurred to me that some of this info might be of use to someone else who uses a small metal bandsaw for this kind of work, especially if their bandsaw doesn't like to cut very true at the moment. I've been forced to learn how to set up my two woodworking Bandsaws to do all manner of ripping and resawing over the years and all the same principles apply to the metal cutter.
The Wellsaw is not a bad little machine, although I have read accounts on other BBs by people who think they are junk.
I don't think I would pay 2.5 K for a new one, but this one cost me $200 about five years ago and came with a coolant pump and reservoir.
It's very important to get a good blade on there. I'm using a 10-14 TPI Bi-metal vari tooth by Simmonds and it works well for most things. I have had some cheap and some not so cheap blades on the machine that could not be made to run true no matter what.
The bearing guide assembly needs to be set up properly for the blade to run true. One of the bearings tightens into a fixed postion, the other is on an eccentric for adjustment. I remove the blade and use a short piece(3-4") of old blade to adjust the bearing clearance. It's too hard to tell what is going on in the guides with the full length blade in place. The twist in the blade makes it impossible to tell when the bearings are set perfectly.
I like to set the bearings up with enough clearance for the blade plus a few thou to spare.
If the bearings are set so tight on the blade so that they squeeze the blade rather than just guide it, the blade gets distorted fairly quickly and won't stay on the machine.
The plate that the bearings mount to is also designed to be adjustable. I use trial and error here. Start with the top and bottom guide plates tightened up in a postion that is flush or in line with the pads they mount to.
If the machine moves into the cut as it drops, then loosen the cap screws that hold the plates and rotate them a tiny bit away from the cut, vice versa if the machine was moving out of the cut as it dropped. After a few tries it should cut nice and plumb as it drops.
About the only other thing is to maintain enough tension on the blade so that the horizontal part of the finished cut is true when checked with a straight edge. Don't overdo the tension though. I found out the hard way that this tends to cause blade breakage.
These few items are about all that is needed to get nice true mitres out of this little machine, which though compact has pretty decent capacity and a really nicely made, very skookum vise.
Hope the is of help to someone.