Am I being silly?

[brman]

Tack weld opposite points. Progress slowly and methodically, setting up as accurately as you can and measuring as you go. All you need is a stick welder, a grinder, and a tape measure.

Then level with epoxy. It's completely doable, loads of people on here have written about their experiences and how to do it. If you screw it up (like I did my first time) chip it off and try again.

Alternatively, skip the hard stuff and use aluminium profile. You'll be bolting your rails on in minutes rather than days or weeks (or you know, in my case, months).

Which I think highlights my problem. careful welding (with lots of practice first), epoxy levelling. It just isn't going to happen. I need to find a easier route or just not bother.

If you want to cut metal on the machine,just find an old mill and add ballscrews and steppers.It may go over budget but it will work.Cutting metal on a woodworking machine may,just,sort of,be possible.That doesn't mean its a really good idea and trying to do it on a machine with a lot of Z travel, with all the consequent magnified play in the system won't help.For a hobby machine that just cuts wood you can do some stuff with a wooden machine.There are some extremely lightweight machines all over youtube delighting their owners,even if they wouldn't be much use in an industrial environment.You just have to be realistic about balancing budget,usage and building ability.The answer is out there once you carefully consider which features matter most.

Which is where I am at the moment, trying to balance time, budget and quality. I've seen pictures of high quality machines and, while I probably have the ability to make one, I don't have the time (or inclination). I have also seen MPCNC cutting ally acceptably (to me, not a production engineer) on youtube. So the question is really how low can I go without wasting my time?
I am tempting to try and see but I just know that will be followed by a lot of people saying I told you so...... ;)