Questions for my first CNC Router (for aluminum)

[slickrick]

Hello everyone,

OK, so I am planning on designing and building a CNC machine. Initially my plan is to build a small X Y machine that will specifically be to cut out aluminum pieces. The aluminum is 6061 T6 0.050 thickness. And the smallest cut will need to be 1/16".

My strength is in the design and build part of the project, but I am having a tough time finding information about the motors I need. What size motors would I need for a 12x12 table, with a low gantry (no Z axis on this first one), that will have either a cheap (harbor freight) dremel, a variable speed drill motor, or if needed a black & decker router.

Also, how would I go about sizing the motors for my second table which will be at least 30x48 (gantry spanning the 30), having a Z axis motor, but still only having to cut .050 thick aluminum, just larger pieces.

Thanks guys
Rick

[slickrick]

Well, I am having a few problems with my design.

Since this will be an inexpensive design, and I plan on using as many parts and pieces I can scrounge around work, I am going to use all thread rod and rod couplings. I am going to get some round stock for guides, and most likely be using aluminum angle for most of the frame. I plan on buying some thicker pieces of aluminum where needed.

A couple problems I need to solve are what slides over the round stock, the best way to connect the allthread to the stepper motors (not yet purchased), and how to minimize backlash with rod couplings.

Can you guys point me in the right direction? Links here, or elsewhere that can help me would be appreceated. Thanks
Rick