[wwendorf]

Hi Everyone,

I'm starting out on building my first cnc machine from scratch, so I figured that I would create a build log about it here. It will be a 2' x 4' router table, gantry style. The goal for this machine is to cut primarily wood. The main use will be 1/16th in hobby ply for use in RC Airplane kits. However, I ultimately still want it to be able to cut aluminum, so I'm trying to build with that goal in mind as well.

I'm planning on using a porter cable trim router for the woodworking spindle, but for metal, I have a Sherline head that I may try using. I may also build my own spindle assembly with an R8 taper in it, but that will be worked on after the wood router is built. One of my future wishes is to have a spot on the machine with a solid state pumping laser diode at 380mw so that I can do engraving on both metal and wood. I'm aiming for accuracy of +/- .001, but will be happy with +/- .003.

As I have a fair amount of aluminum in stock that is 3 1/2" wide x 1/2" thick, I am planning to use that, as well as some 1.25" wide x 1/2" thick material for a bit of structural bracing. I'm also planning on bolting the entire machine together.

I got rather lucky and picked up a fully functional Z axis with what I believe is a ball bearing precision ground lead screw on twin rails which cost me $35. It even came with a stepper motor with encoder (see pics), tho I may not wind up using that particular stepper motor.

I also found 2 - 25 3/8" thk linear slide rails for $15 each. I'm going to use those for my Y axis which the Z axis will ride upon.

I have also purchased some Glacern supported linear rails and ball bearing blocks for the X axis which are 30mm x 1250mm (a little over 49") long. I also purchased 4 bearing blocks which will support the gantry.

I have attached drawings done in alibre which show the layout for the gantry.

I have a Syil SX3 (converted to X4 electronics) which I will be machining the various parts and pieces of the router on. As I'm making some rather long pieces that will need drilling and tapping, I will be pushing the capabilities of my mill to the limit, but I think it will turn out well. I may use 80/20 extrusion for the table assembly, but I haven't decided on that one way or another yet.

I guess that's good for an introduction, so i'll close for now. If anyone has any suggestions on what i've drawn so far, I'm eager to hear from you.

Also, I'm looking for good suggestions for an electronics package and a good source for leadscrews and ball nuts. I've been considering the 405in/oz 3 axis kit from xylotec, but i'm just not sure yet. As far as lead screws, i'd really like to go with ball screws and precision ground or rolled leadscrews, but if I can find a good option with good accuracy, i'd also consider acme screws. I still think i'm going to be stuck with ball nuts tho in order to get the accuracy I want.

Thanks,
Wade