Hi, Looking to build my first cnc, Just wanted to get your opinions on the machine design, The goal is to make pinewood cnc furniture as well as large foam models. So i have tried to make a machine that has a Adjustable Z, so it can be lowered for wood, then raised for foam. I have also mounted it on a wood base with cutouts to allow the x supports to move. I chose the wood base because it is cheap! and should give good rigidity to the y axis's Do you think this is a sound design that will meet my goals? Your opinion is appreciated. Cheers, Blake
The taller your Z axis, the wider your Y plates should be. The way you have designed it will be prone to a lot of flexing and bowing of the Z axis, you have a very long lever there.
A couple more issues you need to consider. First is the amount of weight you will have swinging around way up in the air as the gantries move about. The inertial forces from that motor will impart significant prying forces on the wheel axles and over time cause looseness in the system. But this becomes a non-issue when you consider the second issue here. The Z-axis movement need not be any longer than the longest bit you have to work with. In other words, you can't cut to the bottom of a 10" block with a 5" bit. You get the 4" available into it and the collet begins to hit the block.
First thing I would say (throw in my 2 cents ) is great looking Build @pajamers you have going on here and I believe it can serve your needs perfectly cutting large foam blocks and lowering down to cut the pine sheets. I do however think your Z actuator is unnecessarily too long even with the X at the top of the column height so I would revisit this. Also like Rick stated your bit length will play a main role in how you think about the dept of cut for this machine. You can feed large material in but your limited by your cutting depth. Again a lot of factors play into this such as sourcing longer bits or 3D carving and or material flipping that can make this work. It really depends on the details of the application that you are after but I doe feel your on the right track. Keep up the good work.
