Whenever you open UCCNC, the very first movement you should make with your machine is "Home All". On a STEPCRAFT, the homing procedure begins with the Z-Axis, then the X-Axis and finally the Y-Axis. Each axis will run towards its limit switch until it engages the switch, then will run the opposite way until the switch disengages. Once all three axis have hit their limit switch, your machine is now ready to travel the full length of each axis!
This is known as a reference movement for the machine. Without this reference movement, the machine has no idea where it is along its axis and may not travel the full length back and forth. If your machine is stopping short of the full length of travel and you aren't noticing any binding, make sure to "Home All" and try running again.
One important thing to note is that if any axis ever travels in the opposite direction of its limit switch when homing, check to make sure a limit switch is not engaged somewhere on the machine. All of the limit switches are on the same circuit, so if you tried to home your machine and the Y-Axis limit switch was pressed, the Z-Axis would travel in the OPPOSITE direction. This happens because the machine is going through the stage of homing when it backs away from the switch until it disengages. Because the Y-Axis switch was pressed, the Z-Axis will infinitely try to move away but it will never disengage.
The purpose of any CAM program is to take your design file and turn it into G-Code by assigning tool paths to your project and outputting it in a format that a CNC machine can understand.
That being said, you still need a method of controlling the CNC machine, which is where programs like Mach 3 and UCCNC come in. They are designed to connect to the CNC machine and the G-Code files that you create in your CAM program are loaded into Mach 3 or UCCNC to run the machine.
With any CNC router, you have three main steps to creating a project:
Design your project in a CAD/Drawing program
Use a CAM program to assign tools and tool paths to the project
Use a machine control program to load the G-Code files and run the CNC machine.
The D-Series 420, 600 and 840 all have a max Z height of 140mm (5.51"). However this does not represent the maximum height of material you can process. From this height you need to subtract the spindle collet nut stick out as well as the length of the cutting tool you are using.
The following represents the spindle and spindle nut stick out you get on a D-Series machine with the HF-500 and MM-1000 spindles
NOTE: This is the case with just about every CNC machine on the market, not just STEPCRAFT CNC. Most all CNC machines will have spindle and spindle nut/tool holder stick out that takes away from the usable Z height.
So if you take into consideration the MM-1000 with dual spacers, you would have a total Z height of 140mm (5.51") minus 26.34mm (1.04") leaving you with a new max Z height of 113.66mm (4.47").
Now depending on what you intend to do, you can use this new value to plan your project. If you want to cut all the way through material, you would need to have a tool that is long enough, which you would further subtract from the new Z height value.
Example 1: New Z Value is 113.66mm (4.47"), if you divide that number in half, that would mean you can use a piece of material that is 56.83mm (2.23") thick and the tool would have to stick out 56.83mm (2.23") as well.
NOTE: This would also mean that the cutting height of the tool would have to be a min of 56.83mm (2.23") or you run the risk of rubbing the shank of the tool on the material.
Example 2: If you intend to only engrave on top of a piece of material, then your tool stick out can be much less. If you use an engraving blank that sticks out say 12mm from the bottom of the collet nut, then that means you can have a max material height of 101.66mm (4").
NOTE: please keep in mind you should also allow for a couple 2-3mm of Z height clearance for rapid, non-cutting moves on the CNC as well. So you would subtract another 2-3mm from the above numbers in a practical application.
TWO SIDED MACHINING - For thicker material
One way that you can increase your max material thickness that you can cut through is using double sided machining.
Example: You can take your new Z value of 113.66mm (4.47") and divide that into thirds. This would mean you can have a material thickness of 75.33mm (2.96"), or two-thirds and using a cutter with a length of 38mm (1.49") you can cut one side of the project and then flip it over and cut the other side - so you are using a shorter cutter to cut through a thicker material by cutting each side.
The Mini Tool Adapter is used to reduce the size of our 43mm x 20mm adapter down to an 8mm hole so you can use STEPCRAFT attachments like the Engraving Point, Plotting Pen or 3D Touch Probe, which all have an 8mm shank on them.
Alternatively you can use an 8mm Collet in your spindle (Just be sure to power the spindle OFF) when running these attachments.
Cura does not come with the Stepcraft PH-40 as a pre-configured printer, and thus requires creating a custom printer profile (please see the PH-40 First Steps UCCNC manual for more information). Below is a PDF containing the parameters for your Cura profile. Please note that the nozzle diameter setting is dependent on what size nozzle is fitted to the print head.
A surfacing bit typically has a larger than normal cutting diameter (1 to 3 inches) and are used to flatten or level uneven surfaces on your project material. They are also used to take the thickness of a material down to a final required size. For example, you might have a piece of rough cut lumber that measures 1 inch in thickness but you need it to be 3/4 inch thick. If you don't have a surface planer in your shop then you can use a surfacing bit with a pocket tool path to plane the material down.
Another common use for surfacing bits is to clean up and level a spoil board. After continuous use your spoil board's surface will have a lot of cuts in it and you might want to clean it up so it is perfectly smooth again. A surfacing bit is perfect for this, especially with machines where the spoil board is physically attached to the machine - you might want to prolong the use of it for as long as you can before replacing.
Leveling your spoil board is also important. If you are looking to engrave .005" into a piece of metal and your bed is off by a couple thousandths from one side to the other or front to back, then the thickness of your engraved lines will vary. By using a surfacing bit, you will ensure that your spoil board is perfectly level in relation to your gantry which will result in a uniform engraving.
Note: Because of the larger diameter of a surfacing bit, it is important to note that you can not take as deep of passes or run as fast as you might with smaller end mills on most machines. Consult your machine's manufacturer for assistance with proper speeds and feeds for surfacing bits.