HI;
I have a Grizzly G1007 mill/drill and it is adequate for aluminum but on steel it wanders a lot. I have tried cutting 1/4' slots in 1/4" steel angle and the cut moves a lot. Plunge down to start the cut and when cutting the slot it will be
off from the plunge cut. The return cut will be different, also.
I think the problem is as a previous writer stated, the round column mills flex a lot. I've tried some boring in cast iron and you can see the whole spindle flexing as the boring head rotates.
I eventually want a Bridgeport clone like the ones Grizzly sells. I just can not
justify the cost. I am retired and just putter around. I live 40 miles from the Grizzly showroom in Muncy,Pa. I like the Grizzly equipment and have a 12X36 lathe, a metal cutting bandsaw and the mill/drill.
My 12x36 Grizzly lathe has quite a bit of flex in it too. When I want to do precision work I use a toolpost grinder in my lathe.I previously had a 6 inch Craftsman lathe and it flexed a lot more than my Grizzly. If you want to do good work on steel the more massive the machine the better it will be.
I like the idea of getting a used Bridgeport clone.
Have fun.