Quote Originally Posted by GEOFFREY View Post
With a smallish (600x400?) working area and a strong solid fixed gantry machine, I do not see why steel should be
too much of a problem. My machine (converted commercial PCB drill/router) had a steel section right across the middle of the aluminium table that was used to locate dowelled stacked boards for drilling etc. Careless use by the previous owners operatives has led to to both the alluminium and steel parts of the bed covered in holes and grooves all over the place!!! These have maily been cut with sub 1mm cutters, which probably did end up breaking, but not before inflicting serious scars everywhere. With a slower speed spindle, and the right cutter I feel sure that I could cut steel, but would not need to be greedy with regards to feed speed DOC etc. G.
Strong Fixed gantry machine is the correct choice for larger foot print when cutting steel with correct spindle attached. Moving gantrys will cut steel with correct spindle but are less than ideal unless massively built.
My router which in the grand scheme of things is weak compared to even lightest duty milling machine as cut steel on the odd occasion and even cast iron. But it's not really practicle or advisable as it knocks the stuffing out the machine and takes an age to cut due to restrictions on feed and DOC.

The whole reason or point of my objections is that one machine can't cut every material correctly and when comes to steel a moving gantry design is not practical due to the strength needed and all that it brings with it to the build. Far cheaper and easier to build/buy to separate machines each designed for it's purpose.