I would like to show off...errrrr...criticize my Z axis design and get some opinions on it. This is my first SW drawing.
I want to cut mostly plastics and aluminum with the possibility of doing a bit of steel if I have to.
[This looks like a heavy-duty machine, and it will probably be able to cut aluminum, if you keep it all as sturdy as it seems. But I doubt it will be a good machine for cutting steel.]
I am planning a steel-construction moving gantry 3'x4'x1' machine. I have not yet fully designed the machine.
[Why don't you keep designing, before buying materials piecemeal? You'll doubtless need more aluminum for the rest of the machine, and you might as well get it all at once. It's amazing how things change, as you consider how the different parts interact. If maximum rigidity is a consideration, then a moving-table design beats the moving gantry approach.]
I have bought all of the linear rails I intend to use as well as the Z axis ballscrew.
I want to order the aluminum by tonight from Enco while they have their Cyber Monday 20% off + free shipping. This is kinda important due to budgeting.
[While Enco's a good place for import tooling, I don't believe that they really put out that great a deal on metal stock. Shop around a bit for your aluminum; you might be surprised...]
1) What thickness aluminum plate should I be shooting for?
I figure the plate that meets the gantry could be 3/8" or 1/2" and the router-mating plate should be ~1" thick. I see overkill as a good thing.
[I'm not sure about that - at a certain point, it's just dead weight that your motors have to push around. 1/2" is probably plenty thick enough.]
2) Should I consider elevating the linear rails in order to get around having to remove the middle section of the router-mount plate or is it better to just remove a portion of the plate (as shown)?
[Yes, you should deeply consider how this all fits together. But it might make more sense to mount the ball-screw on the back side of the plate you're mounting the router on, and to make clearance for it without sacrificing the integrity of the structure. Of course, it's also good to keep the router as close to its supports as possible, to minimize adverse leverage.]
3)The amount of Z travel is based on the ball screw I bought. Should I leave the travel the way it is or attempt to reduce it to minimize flex?
[It's hard to say - what size parts were you thinking of making with this? You need your longest tool to clear your highest part.]
ComputerSculpture.com — Home Page for Discount Hardware & Software