If you’ve never used a CNC machine before, we recommend learning the basics on the X-Carve machine before using the 4×8.
Once you’ve made a simple project with it and learned the basics of CAD/CAM software, speeds and feeds, end mills, and toolpathing, follow the steps outlined below to get access to the 4×8 machine.
To get signed off on the 4×8, attend a 1-on-1 training session with an authorized trainer. When you arrive at the training session, you will need to bring a project with a CAM design already prepared. The CAM file must have been created by you and not a third-party or downloaded file. You should be able to modify the file on site (bring a laptop, or if using VCarve Pro, use one of the computers with VCarve Pro installed. To schedule a 1-on-1 session with a trainer, post a request on the CNC Slack channel or email [email protected] The certification form must be signed by you and the trainer for you to be signed off on the machine.
If you are not running a program but operating the CNC manually (e.g. surfacing a board), you do not need a CAM design to get signed off to operate the machine. In this case, you will only be allowed to operate the machine manually until you get signed off to operate the machine with a CAM design.
|Make and model||Sequoyatec 1325|
|Work envelope||4' x 8' x 0.66’ (1300 x 2500 x 200mm)|
|Spindle power||3KW, water-cooled|
|Transmission||Rack and pinion for X and Y, ball screw for Z|
Note: Several upgrades have been made to the machine since we purchased it, including but not limited to:
The spindle is water cooled. To protect the spindle from overheating, coolant must be flowing while the spindle is in operation. To ensure coolant is flowing, check the flow indicator attached to the spindle. Do not start cutting material if coolant is not flowing.
The following is an overview of the control interface upon startup.
The buttons on the control interface can be controlled with the with keyboard, mouse, or touchscreen.
The X,Y,Z coordinates of the cutting bit in relation to your work zero position. The work zero position should have been defined in CAM and must be set in CNC12 before running you program. If work zero is not set in CNC12, the controller will not know where your stock material is located, and a crash may occur.
The X,Y,Z coordinates of the spindle in relation to the Home Position of the machine. These coordinates do not depend on the location of your stock material and can only be reset by homing the machine (Reset Home).
Spindle Control allows you to manually set the spindle speed. Normally, you do not need to use this panel because the program should control the spindle automatically.
The Jog Panel is used to manually move the spindle. There are several circumstances in which you may need to jog the spindle:
Cycle Start begins the execution of the currently loaded GCode commands. The GCode commands to be executed may be
Cycle Stop stop the execution of the GCode commands being executed.
When you home the machine (“Reset Home” button), it finds its home position by gradually jogging towards the limit switches until each homing switch is triggered.
Keyboard jogging is highly recommended because it seems more reliable and less likely to cause a crash due to buggy control execution.
You can close the cheat sheet while leaving keyboard jogging active by closing the window. Keyboard jogging remains active as long as Keyboard Jogging Active is displayed.
The spindle uses a collet to hold the bit securely while cutting. The collet diameter must match the shank diameter of the bit exactly.
TODO: Insert photo of bit and collet.
The Sequoyatec comes with the following collet sizes:
Make sure you are using the correct size collet for your shank or the bit will come lose while cutting, destroying the bit and the collet.
Follow these steps to install the bit:
Make sure to insert the bit all the way up to the minimum insertion line. Having the bit stick out too much can damage the bit and the collet. If there is no minimum insertion line, insert the shank of the bit as far into the collet as possible.
TODO: Insert photo of minimum insertion line
The zero position of your stock material was defined when you created your CAM program. Now, the corresponding zero needs to be set on the physical machine in order to tell the controller the location of your stock.
Setting Z zero can be done using the touch probe, or it can be done manually.
Before setting Z Zero with the touch probe, check to make sure that the controller detects contact between the bit and the touch probe.
Press Alt-I on the keyboard to display inputs.
Touch and release the touch probe from the bit several times. Verify that Input 7 (touch-probe input) is toggling. This verifies that the touch probe is correctly sensing contact with the bit.
Press Alt-I again to exit out of the Input Display.
Setting Z Zero can be done before or after starting your program. Whenever there is a tool change in your program, including when you first run a program, the controller will prompt you to complete the Z zero touch-off sequence. You can skip the Z zero touch-off sequence in-program if you have already set Z zero out-of-program. In any case, follow the sequence below to touch off the bit to the Z plane.
TODO: Add images
If you prefer not to set the X,Y Zero positions manually, there is a fixed X,Y zero position that is located at the bottom- left-hand corner of the plenum (see image). To use this fixed zero position, simply place your stock so that its X,Y zero position is at the fixed X,Y zero position and run the M57 macro command by pressing “M57” or entering “M57” into the MDI command prompt. The controller knows where this position is because it is a fixed position in relation to the machine home position (discovered when the machine is homed by pressing “Reset Home”).
TODO: Change photo for fixed zero position
There are a couple of sets of steel clamps you can use to secure your stock to the spoilboard. A minimum of 2 clamps are required to hold down a single piece of stock. Note that steel is a hard material, so you should always check your toolpaths to ensure the clamps are not struck by the bit, spindle, or dust shoe. When in doubt, it is safer to use double-sided tape.
The Sequoyatec has been fitted with a vacuum table and vacuum pump which enable users to hold material down using vacuum suction. Vacuum hold-down has a few advantages:
Vacuum hold-down works well with flat material that has a large surface area (e.g. sheet goods). It does not work well with uneven surfaces (e.g. rough-sawn slabs) or small surfaces (e.g. < 1 square foot).
The vacuum is distributed underneath the spoilboard by a network of PVC pipes and a grid pattern called the “plenum”.
The vacuum is pulled through the MDF spoilboard. To use it, simply place material on top of the spoilboard, open the appropriate zones, cover any exposed MDF in the open zones, and turn on the vacuum pump. The strength of the hold-down can be tested by pushing on the material to test how much force is required for it to move.
TODO: Insert image of electrical panel vacuum pump on off
TODO: Insert image of part being held by vacuum table
TODO: Insert image of covering up exposed area of vacuum table
If you use the vacuum table, please read Spoilboard Maintenance section in Maintenance
Information about the design of the vacuum table can be found here: Vacuum Table Design
There are myriad ways to hold down stock. Not all methods can be covered here. Some popular methods include using double-sided tape, using painters tape and CA glue, and using a separate spoilboard that the stock is screwed down onto.
A GCode file is the file output by the CAM software (e.g. Fusion 360 or VCarve Pro) using the appropriate post-processor. The GCode file is the file that is run by the controller to execute the toolpaths you designed. A GCode file is a plain text file and can have any of the following extensions:
However, no particular extension is required for the machine to read and understand the file.
After you load a tool, CNC12 will prompt you to begin the procedure of setting Z zero. If you have already set Z zero, you can skip this step by entering 0 (“Continue without resetting Z0”).
Turn on the dust collection as explained in Activating the dust collection system After Z zero is set, when you click Cycle Start, the program will begin. Note: At this point, be prepared to shut down the program (Cycle Stop) in case you made a mistake in CAM or in setup that would result in a crash.
Consider doing an air cut prior to actually cutting material. To perform an air cut, set Z zero to be above your actual Z zero, so the bit will hover above the stock without actually cutting anything. When you have verified the program with the air cut, restart the program with the correct Z zero.
TODO: Shrink images to just code
The following video demonstrates how to put the dust shoe on the spindle after installing a bit and setting Z zero. It also demonstrates how the quick-change handle can be pulled off of the dust shoe, which is useful for vacuuming up dust from the table.
Coolant is most useful for cutting aluminum because aluminum tends to adhere to the bit without some sort of lubricant. Do not get coolant on the plain MDF spoil board. In order to use the coolant mister, you must put a protective barrier between the MDF spoil board and your part. Another piece of MDF works. The exterior-grade MDF T-slot panels are also a good option.
TODO: Insert image of coolant mister
Todo: Insert image of protective barrier
TODO: Add screenshot of ethernet connection issue
There is no known solution to this error except to restart the controller and/or computer and hope the error goes away.
Sometimes when pressing one of the jog buttons (e.g. +x, -x, +y, -y, +z, -z), the machine will continue to jog even after you've released the jog button, causing the spindle to crash.
The uncontrolled jogging can be stopped abruptly by pressing any of the other jog buttons. Therefore, it is safer to have quick access to the other jog buttons in case of uncontrolled jogging. For this reason, it is better to use keyboard jogging because you can place a finger on more than one jog button at a time.
TODO: Add screenshot of limit switch triggered error
When attempting to Home the machine (by pressing “Reset Home”), sometimes there an error occurs in which a limit switch has been triggered. This can be fixed by moving the spindle away from the Home position prior to homing. Simply reset the control, jog the spindle slightly away from the Home position, and then run the homing routine.
Because the effectiveness of the vacuum pump relies on a flat and relatively smooth spoilboard in order to minimize leakage, it is important for all members to do their part to ensure the spoilboard is flat and free of gouges.
On occasion, a user might want to cut all the way through their stock material, in which case the bit might end up cutting into the spoilboard. If this is the case, make sure not to cut any deeper than 0.02” into the spoilboard.
If you do find yourself cutting all the way through the stock material and into the spoilboard frequently, please volunteer to occasionally resurface the spoilboard after it gets marked up. There is a 2“ surfacing bit available to users for resurfacing the spoilboard. ONLY USE THIS BIT FOR MDF and NOTHING ELSE.
If you do end up gouging the spoilboard (it happens to the best of us), the spoilboard can be repaired with Durham Rock Hard Water Putty.
Check the video from Dallas Makerspace to learn how to repair a spoilboard:
Lubrication of the linear rails (aka ways) and the single Z-axis ballscrew is important to ensure longevity of these components. The machine should never be operated with dry bearings. These components are all connected to a single-shot lubrication system. This means that all of the bearings can be lubricated with a single press of the lubricator lever. This lever should be pressed after every several hours of use.
TODO: Insert photo of lubricator
The retrofit was documented and submitted on the Centroid CNC forum: https://centroidcncforum.com/viewtopic.php?f=57&t=5012