(CNC.rar)

Now, the device consists of four quadrangular pieces with a 37cm long side. Respectively, a 37x37 bottom, 37x37 sidewalls, a 34x37 backwall, and a 9x34 frontwall. Next I drill holes and make sure they are 7сm away from the edge and put the whole thing together using 3x40 self-tapping screws. To prevent the walls from cracking, use thin screws.Cut a 2mm-wide groove for a metal angle all the way along each sidewall, just 3mm above the bottom. These are going to be Y-axis guides.Take a 20mm angle and make two 34mm work pieces. Drill holes at 45 degrees into the corners and bolt them to the sidewalls.You can start with aluminum angles, but I prefer Soviet duralumin ones, because they last for more than 300 hours of work. Verified and approved!



Attach two 14cm angles, each having three F8mm holes, to the base of the table. Attach two 608ZZ bearings on the top and one below using M8 L25mm bolts. The table should move smoothly.Drill 22mm holes in the lower middle of the frontwall and backwall, just 5mm from the bottom, using a Forstner drill bit; the one in the backwall should be a through hole (for the Y-motor); the one in the frontwall should be 7mm deep. Here we are going to fix a thrust bearer for an 8mm pin.



Start an elongated M8 nut on the pin. The nut should have two F2.5 holes along the length and a M3 thread.I chose not to mess with the X-axis. Instead, I cut holes in the sidewalls and inserted standard 9mm Epson guides, on which I fixed shortened runners with bronze bushings. Then I placed a transmission in the middle, which consisted of the good old M8 stud-bolt and the elongated nut with two holes and a M3 thread. The X-bolt is driven by a 55mm stepper motor.Needless to say, this one is from an Epson too. The Y-axis is driven by a Nema17 motor (42mm).Instead of a joint box I use the following thing, both in 3D printers and machines:Then I cut out a bushing for the motor’s shaft, drill a F2.5 hole on the side, cut a M3 thread, fix it on the shaft and tighten it.Use a M8 drive-in dowel:If necessary, shorten it and glue it onto the end of a metal pin using superglue.Then I fix a rubber pipe from a standard flexible connection pipe onto the dowel and the motor’s drive adapter.Now I have a flexible reducer bushing. I prefer not to use clamps.Now the Z-axis. This has to be the hardest part of the machine. To make things easier I use standard F8mm guides – rods and linear slideways. The base consists of bearing holders, and the construction is borrowed from Sir Graph.Plywood (6mm)Use white glue to connect plywood parts, and Epoxy or superglue to glue in the bearings. Fix a nut via the through-holes.Buy a 80mm bracket for planks in Castorama and drill a F19mm hole in it for a spindle shaft. I use Dremel 300.Connect the bearing block and the spindle bracket using ten self-tapping screws.

Cut the base for the Z-runner out of a 15mm plywood piece. Dimensions:Base: 150x90mmTop/bottom: 90x50mmCut a hole 7mm deep in the top part using a Forstner drill. This one is for a 608ZZ bearing.



Put the top and the bottom parts together and drill F8mm holes for the guides .This is what the assembled base should look like:

Fix a motor holder at the top. I used only two self-tapping screws so that it could rock back and forth and create room for axial alignment between the pin and the motor.Fix the Z axis:



Bolt four plywood 15mm sheets (see the picture above) to the table, then bolt a 16x24cm table to the sheets.

Cut clamps out of a 6mm plywood sheet and glue them.The result should be something like this:

I use standard electronics from printers that feature LB1745 + 12F675 microchips or StepSticks.In the first case I used a power supply from a 42V printer;In the second case – a 12V/5-25A LED power supply.



Controlling the device:1. Mach3 via a LPT port (see the pic)2. Via USB GBRL + Arduino Uno with the following type of shield:Finally, some specifications:Printable field: 160x240mmVertical: 70mmCutting: plywood (up to 15mm), glass fiber laminate (up to 3mm), plastic, wood, etc.Engraving potential: materials not harder than nonferrous metalsSpeed: usually 2mm/secWell, if you find this post interesting I’ll write Part 2 and tell you how to make a dust protection cover.This video shows a device running at 1mm/sec. Not so fast, and it uses a 3.175mm cutter. Too big for a Dremel. You can even hear it. A 1.6mm cutter would make it twice faster. Usually, I set 2.5-3mm depth for Dremels.