Now on to the progress so far.
I, after much gnashing of teeth have got one axis moving. Bear in mind that I am not one who puts alot of details on paper before undertaking a project like this. My reasoning is that if I find that something was a bad idea, there is no black and white record that the idea ever existed.
So, I have one axis assembled. Really, it is just a test fitment. Welds need to be finished and sandblasting and painting needs to be done, but the fact that things fit together and move is encouraging. I still have issues with the speed at which things move, but I am confident that will be overcome with a higher voltage p/s.
That's it. I did purchase the rails for the short axis today. I have chosen to use 1.625" round stainless tubing for the short rails. I am using skate bearings for all linear motion. My long axis is the gantry which is 60" long. I am using 1.5" square mild steel tubing for that. I'm sure that somebody will tell me that is a bad idea, but I'm stubborn, and I like my own ideas, and this seems like something that should work, at least for awhile. Now that I know I can get stainless tubing for a reasonable price, I may eventually change to that, but for now...
My motors are 100 oz*in motors from the HP3 printer. They will be driven by an as-yet-undetermined driver circuit. I am probably pushing the limits of these motors, but I can always upgrade. My goal is 45IPM. I have no real load except momentum and friction. Friction should be minimal. Momentum I think I can overcome by approaching desired speed and stops gradually. We'll see.
I intend to have a 60"x24" cutting area. With the gantry spanning the wide dimension, I can place the end (or the middle) of a full sheet on the table for processing. For now, everything I intend to cut will be smaller than this. I'm sure that will change eventually. I am designing the short axis to be expandable, so when I do decide that I need a bigger cutting area, I can add to it. One of the reasons for keeping it short is that floor space is limited, and right now I can deal with the smaller work area easier than I can deal with no room in the garage.
I can't think of much to add right now. I will have to take some pictures of what I have so far and post them, but it's late and I'm tired, so they will have to wait.
I welcome feedback, advice, and questions. I will do my best to answer questions, but remember I am still sorta new to this. Don't let your feelings be hurt if you offer advice and I don't take it. Like I mentioned, I generally like my ideas, and because I'm stubborn, I reserve the right to reject your advice until my idea doesn't work.
Later...
Dave