I am looking at building myself a cnc machine and I have set a budget of about $5000. This will be my second build as I have already built a modified Momus machine. The reason I am wanting to upgrade to a new machine is that I have found that I have reached the limit of the machine and in order to be more productive I need faster feed rates or to be able to make deeper passes, which is not possible on the machine that I have. So I have been thinking a bit about the next build but would like to get some suggestion and input on which direction I should be going. For the machine I will be cutting lots of fiberglass sheet and aluminum. I am able to do the job now but it is slow.
So here is an idea of what I am thinking. Build my own frame or buy the 48"x48" kit from cncrouterparts. If I buy the kit, it would be easier to build but will I get as much out of the machine as I would by building my own.
Frame
Home built or purchase - I have built my last machine frame and am able to build the next but I have been wondering if it is worth it or just better to buy a frame.
Rails
Have considered two option. V-bearing or LINEAR MOTION RAIL GUIDES from THK - If I bought the kit it comes with the v-bearing, but if I build my own frame I could choose. Which will be better for what I am trying to do.
Motion
Rack & pinion or ball screw - I have read that the ball screw is slower but holds better and has zero backlash. Speed is not a big issue as is accuracy. The jobs that I am doing are small, just right now I am having to do 4-8 passes to complete the cut where as with a better machine I hope to do it in 2 - 3 passes which would speed everything up.
Z axis
Even if I build my own frame I have considered buying a z-axis that is already built and ready to go. I want something that will be up the task. So even if I build my own frame I was considering getting the z-axis from cncrouterparts. Will this z-axis be up to the job or is there another source in which I could get one that would work better.
As I said I have set a budget and that budget is what I need to buy the complete kit from cncrouterpart. But then I wonder if I would get more for my money if I build my own. Any suggestion on whether I buy or build would be great. And if I build which option should I consider to get the most for my money.
Thanks in advance for any help you can provide.