[Bryan1]

G'day Guy's,
Well nearly 4 years in the making and I'm nearly there, this is my first attempt at building a cnc the size is 650x350x170mm. I spent ages palaying around with acme screws and all thread only to ditch all the hard work and go for some cheap ball screws off ebay.

This is a veiw of the rear of the cnc, the cutting table is some 20mm thick resin board that is used in the high voltage electrical industry. The board will drill and tap nicely and is pretty solid.



This is the front of the machine



This shows the x-axis motor arrangement, for the Y-axis sides i used 2 off on each side 25mm linear bearings with 6mm plates. The plate still need to have some 20mm angle put on to beef up the plate



This is the y-axis, I made the main carrier out of a block of cast iron and bored 2 holes to suit oil light bush's. The rod's are 3/4" 4140 and overall there is less than 0.001" deflection. Later if any vibration is felt I'll put a third rod and bearing in to support the Y axis.



This is The Z axis I made from scratch, the lead screw is an acme thread 12tpi which I cut on my toolroom lathe. The block is a piece of cast iron and I have an acme tap to suit so I tapped the hole first then made sure the screw thread was cut so very little to no backlash. The support rods are 10mm rod's I got from an old printer.





For driving the steppers the great guys at the Adelaide uni gave me this 3 amp CC circuit with some circuitboards and they do work great



The axis control boards are the single step Oatley kits and soon I will be making up some micro stepping boards for quicker smoother running. The parallel input board was one I made very early on and I will endup designing and making a new input board



About 95% there and with my right hand in a splint it will be a few weeks before I can finish the cnc but finally I decided to put some pic's on the net.

Regards Bryan

[jasminder]

Good work friend,
It seems that you are making this machine for wood cutting and light machining. As for the three rods on your Y, i would go for 2 suppored rods instead of three or four shafts.
best of luck for the first run,
jasminder singh

[wjbzone]

Brian, Nice work. I have a similar size machine with two 3/4" drill rods for the Y axis. Never had any vibration problems. What kind of bearings are you using on the slides?
Bill

[Bryan1]

Hi Bill,
The Y-axis block is a lump of 1-1/4" x 4" CI and I machined in 2 off 7/8" bores to suit oil light bush's. I had to ream the bush's to get a neat sliding fit and the end plates on the side covers were bored to the exact width. The same was done with the Z axis. Now the as shown with the Z-axis there is a thrust bearing, on the lower is also a thrust bearing.

Regards Bryan