Zünd Overview

Overall Workflow

Like laser cutting, vector-based 2D drawings are used to define where the machine will cut. The depth of the cut is specified in the Zund software and can be assigned to geometry by layer.

There are several different types of tools that can be used with the Zund Cutting System. The GSD has the following options available:

Universal Drawing Tool (UDT) – For drawing lines with a pen.

Universal Cutting Tool (UCT) – For most cutting operations

Electric Oscillating Tool (EOT) – For soft materials such as cardboard, foamcore, or rubber.

Pneumatic Oscillating Tool (POT) – like EOT but with greater blade throw and faster oscillation for thicker materials.

Driven Rotary Tool (DRT) – For fabrics and fabric-like materials.

V-Cut Tool (VCT) – For cutting bevels and v-cuts in foam core less than 1/2″ in width. (Not Pictured Above)

A variety of knives are available for each tool, but material presets are generally configured to make knife changes extremely rare. Only TA’s may change out knives.

Router Module (RMA) – For 2.5D milling of aluminum, thick plastics and other rigid board materials.

The router has the following tools available:

R-118A: .236″⌀ x 1.06″ routing depth (for foam)
R-133A: .1186″⌀ x .433″ routing depth (for down-cutting wood products, hard foam)
R-136A: .236″⌀ x .866″ routing depth (for down-cutting wood products, hard foam)
R-141A: .401″⌀ x .157″ routing depth (V-shape bit for chamfering top edges)
R-202A : .076″⌀ x .23″ routing depth (for plastics, wood, aluminum, laminated aluminum/plastic panels)
R-204A : .156″⌀ x .55″ routing depth (for plastics, wood, aluminum, laminated aluminum/plastic panels)
R-205A: 197″⌀ x .63″ routing depth (for plastics, wood, aluminum, laminated aluminum/plastic panels)
R-206A : .234″⌀ x .86″ routing depth (for plastics, wood, aluminum, laminated aluminum/plastic panels)
R-208A : .118″⌀ x .31″ routing depth (for laminated aluminum/plastic panels only)
P-201A: .217″⌀ x .63″ routing depth (for polishing acrylic)
E7-A: 60 degree x 4.7 mm routing depth engraving bit
E8-A: 40 degree x 7.5 mm routing depth engraving bit

Material type and thickness will inform which of the cutting or engraving tools can be used.

Suitable Applications

The Zund is best used for cutting materials that cannot be cut on the laser cutter, such as plastics and synthetic fabrics or foam rubber that release fumes, highly flammable materials like foam-core and cardboard, or cuts in materials that are larger than the size of the laser cutter bed. It may be suitable for routing smaller sheet stock that would be difficult to mount to the CNC routers, as well as materials that might require extra setup on the CNC routers, such as soft metals (aluminum, copper, brass, etc) and thick plastics, such as acrylic or expanded PVC board, but its 3-dimensional capabilities are limited.

A secondary benefit of the Zund is that, because it uses blades and does not produce heat like that generated by the laser cutting process, there are no burned edges on materials.

The Zund can also be used for more unusual materials for specific projects, such as wax, metal mesh, corrugated plastic, plastic films, fabric, foam and felt.

The Zund is NOT to be used for materials that are easily cut on the laser cutter or the CNC’s, or simply as a time saving measure, such as foam-core rectangles that could be cut by hand. The Zund cannot handle materials over 1″ in most circumstances, and in general cannot do more than 1/2″ with most blades.

The Zund is NOT primarily a router, and should not be seen as an alternative to the AXYZ or Onsrud routers for milling jobs. The router is only used for projects approved by FabLab staff and performed under their supervision.

~~A full list of usable materials is available through the ‘cuttmp’ folder on the GSD server.~~ If the intended material is not listed, work with a TA to define a new material process based on similar materials or by working through a series of tests in the material. You will need to supply enough sample material for testing.

Because force is exerted on the material by the blade moving during cutting (unlike the laser cutter), smaller features may not come out as cleanly or detailed as they would on the laser cutter. In general, the Zund is better suited to larger features.

For routing, offset for the diameter of the bit does not need to be integrated into the file, the Zund will automatically apply the appropriate offset and route along the outer or inner edge of the specified vector, not down the center. ENGRAVE will cut down the center of both open and closed curves. Route (open and closed curves) will be cut to one side of the curve or the other, using the radius of the tool as the offset. An option in the cut parameters for “inside” or “outside” will control this; watch cut direction in Cut Editor or see the dotted line in Cut Center.

Access

Students are able to make job requests and reserve up to 60 minutes each day through the App, reserving only time that is staffed by TAs. Students may request after-hours time through this system, but that time must be booked by a TA. 120 minute limit for end-of-semester, total usage, in addition to the daily 60-minute limit.

TA hours are generally 10 AM – 10 PM each day, 10-6 Friday and 10-4 Saturday, 10-2 Sunday, or as able to be staffed each semester.

File Organization/Prep

Accepted File Types:

EPS / AI (this is best)

DXF (has some issue with curves, possibly the preservation of layer order)

HPGL

Use layers to organize and assign a machine operation to the geometry. Name the layer to correspond to desired the machine operation. Layer order also determines operation order, use the following order of operations as a guide:

Cutting Methods/Operations

Register
- Register uses camera recognition of material edges or printed features to orient the file to the stocks borders accurately. (Visually aligning a laser beam can also be used, rather than the camera.)
- If using rectangular stock, model the stock to register to the edges of the stock (useful for multiple features cut from one piece of stock).
- points or the center of other small features can be used to tell the machine where to find 1/4″ diameter black dots printed on the media.
- (the X0, Y0 axes of the file can also be used to tell the machine where the right and front edges of the media are located).
- When a layer with geometry is imported as a Register layer or another layer is converted to Register, the geometry will no longer be visible, but it is still there, represented by the offset from the origin.
Draw
- Draw is an operation that uses a ball-point pen to plots curves.
- vectors (open and closed).
- fills/hatches.
Score
- Score is a knife cut that goes partially into the material thickness (certain depth or percentage).
- Uses vectors (open and closed).

Cut
- Cut is a knife cut operation that goes through the material thickness.
- Uses vectors (open and closed).
V-Cut
- V-Cut is a knife operation that uses the VCT only, with the blade cutting at an angle on both sides of the curve. Angle must be set physically on the tool, as well as specified in Cut Center applications.
- Uses Vectors (open and closed).
Bevel Cut
- V-Cut is a knife operation that uses the VCT only, with the blade cutting at an angle on one side of the curve. Angle must be set physically on the tool, as well as specified in Cut Center applications.
- Uses Vectors (open and closed)

Engrave
- Engrave is a router cut that goes partially into the material thickness (certain depth or percentage).
- vectors (closed).
  - create separate layers for shapes where the tool should stay to the inside versus outside the closed curve.
- open vectors will cut to with the tool following the curve as a centerline.
Route
- Route is a router cut that goes through the full material thickness.
- vectors (closed).
  - create separate layers for shapes where the tool should stay to the inside versus outside the closed curve.

Correctly set up layers in both Illustrator and Rhino

Files should be clean with as few control points as possible. Check file for floating control points or geometry, or unclosed shapes. When converting from Rhino/AutoCAD to Illustrator, ensure the resulting geometry is completely accurate as some changes can occur during export.

Line weight and color are not read by the Zund, machining operations are assigned by layer names.

If there are multiple layers of the same operation, do not label them Cut 1, Cut 2, etc., simply label all layers by the desired operation and the Zund software will automatically number them in order.

Layer Aliases

There are many ‘aliases’ for each operation, which are the range of acceptable labels that can be interpreted by the Zund.

‘Register’ can be labeled as: Camera, Regmark, Regmarks, Dots, Registration, Register, Reg
‘Draw’ can be labeled as: Draw, draw, sharpie, pen, Sharpie, Pen, Lines, lines, line, Line
‘Score’ can be labeled as: Score, score, etch, Etch, cutting
‘Cut’ can be labeled as: Cut, Straight cut, Through cut, Throughcut, CutContour, CutContourFullCut, CutContourFast, CutContourSlow, Thru-cut, cut, thru cut, Thru cut, CUT, cut, cut through, Cut Through, ThruCut, thrucut, cutting
‘Engrave’ can be labeled as: CutContourEngrave, Engrave, engrave, engraving, Engraving
‘Route’ can be labeled as: Router, CutContourRoute, Route, route, router, routing

Import into Cut Editor, Send to Queue

Import files into the editor, assign material type, thickness:

Carefully measure the stock with calipers and enter the value in the “Thickness” space near the bottom of the “Select Material and Thickness” window. It is recommended that you do NOT change any other settings, materials or parameters.
- To use the calipers, close the jaws completely and press the power button. If the screen does not read ‘0.000 in’, press ‘ZERO’ to reset the calipers. Open the jaws using the thumb wheel, then close fully on the edge of the material. Take measurements from several locations on the stock to ensure accuracy. See: Step by Step Tutorial on Using Calipers
- If the desired cutting material is not listed, ask a TA what an appropriately similar material would be, or work with one to define a material process specific to your objective.

Assign methods to geometry.

Double-click on the layers/methods listed on the right, choose the appropriate method for each.
Or, select geometry and then right-click and either choose an existing method used in the file, or assign a new method type.
Order of layers/methods determines cut/operation order that will be performed by the machine.
- Register as the first method
- Geometry on “none” layers/methods will not do anything on the machine
- Cut internal shapes or draw before cutting out larger perimeter pieces.

Save and then send to queue, the file will then appear in the Cut Queue software.

Double-click on this job to open the file in Cut Center to assign tools and cutting depths to each method, run test cuts and simulations, and to establish reference locations.

Hardware

Vacuum Hold-Down

Maximum cutting size is 98.3″x52.3″

Porous cutting area will pull vacuum through and hold down nonporous materials.

Can be zoned (runs from front-to-back of machine, starting on right side and moving toward left) to increase hold down in the needed section.

Auto-starts at the beginning of jobs, can be set to auto-fit (narrow) to the stock.

Best to check hold-down before starting job (turn on vacuum in Cut Center and try to move material)

Adjustable strength (1-10, most materials use 5 by default to minimize noise)

“Mask”-off areas that aren’t used, but within the length of the zone using cardboard or scrap to increase hold down.

When cutting porous materials, cover with thin nonporous material such as taffeta.

Sealgrip

Must be used when routing or engraving. Be sure that the console display reads ‘overlay on’ so that the machine knows the sealgrip is being used.

Camera

Used for material border and 1/4″-dot registration.

If the camera is not picking up the edge of the stock, lighting can be adjusted, as well as brightness/contrast/etc by right clicking on the camera live feed during the registration step.

Modules

Hold the tools. There are two universal tool holding modules, and one router module that must be attached before routing jobs and removed immediately after. Tool changes are performed by removing and installing desired tools in the tool holder modules.

Performing a Tool Change

Tools

Universal Drawing Tool (UDT) – For drawing lines with a pen. Useful for labeling parts.
Universal Cutting Tool (UCT) – For most cutting operations. Uses a variety of inserts. Does not oscillate, drags blade through material.
V-Cut Tool (VCT) – For cutting angles in soft material. As this tool drags the knife through the material, it is not suitable for very thin material as it lifts the material as it cuts, nor for very thick material, as the material begins to crush rather than cut. 1/8″ – 3/18″ foam core is a reasonable material range for this tool.
Electric Oscillating Tool (EOT) – For soft materials such as cardboard or foamcore. Good when UCT excessively drags or deforms the material.
Pneumatic Oscillating Tool (POT) – like EOT but with greater blade throw. Good with thicker materials that the EOT has trouble cutting cleanly. The POT cuts a little cleaner than the EOT, but because it is pneumatic and runs off the same compressor as the Onsrud and woodshop air hookups, it cannot be used while the others are running. Only use the POT if the Onsrud is not currently operating.
Driven Rotary Tool (DRT) – Uses a rotating circular blade. For fabrics and fabric like materials. Minimizes force acting on the material, but has the greatest overcut due to the blade geometry.
Router Module (RMA) – For routing or engraving materials that cannot be cut with a knife. Uses router bits whose diameter also limits depth of cut, potentially. Small parts may require bridges to maintain connection to surrounding material while being cut.
Kiss Cut Tool (KCT) – For very light duty scoring. Maximum depth of cut is fixed with a rigid “shoe” and set to about 0.005″. Actual depth can be adjusted by spring load pressure (red, yellow, blue). Designed for cutting vinyl adhesive top layer and leaving paper backing intact, but works nicely for scoring Bristol and thin paper and plastics. Not effective with thicker materials like museum or chipboard, use the UCT for scoring those.
Creasing Tool (CTT2) – For creating folds and texture in paper products and cardboard
Perforating Tool (PTT) – For perforating paper products, primarily for folding
Passepartout Tool – (PPT) – For making 45 degree beveled cuts in thin, dense materials. Craft wood, museum, chipboard less than 5mm/0.2″ thick. Complex setup and configuration make this challenging for novice users.

Cutters (Knives and Endmills)

Many knives are available to insert to the tools, with differing geometry based on the intended purpose.

Console

The console directly controls the cutter without going through the software. The console is used primarily for performing tool changes, turning the machine on/off, and switching between online and offline mode.

The gantry can be manually controlled by the Travel keys, and moved rapidly by holding the Shift key.
The vacuum can be toggled on and off by pressing the Shift key and the VAC key.
Pressing any of the Travel keys or STOP during a cutting operation will pause the job and raise the tool until the Online button is pressed, resuming the job.

Light Barriers

The Zund has safety features to prevent injury during operation. The main feature is a series of ‘light barriers’ that are projected from one end of the gantry to the other, on the front and back side of the cutter. If these beams are broken by someone reaching into the operating area, or if a piece of stock lifts up unexpectedly, the cutter will immediately stop operation. The LCD screen will display that a light barrier has been triggered, and will list what barrier was broken. To continue the operation after everything is cleared from the table, press ‘OK’ then ‘ONLINE’ to continue the cut from where it stopped.

While the light barriers are a soft stop, the four red emergency stop buttons located on each corner of the machine are a hard stop. When an emergency stop button is pressed, the operation immediately stops, cancels the current job, and disengages the tools. To continue from an emergency stop, the triggered button must be twisted clockwise to release, then the instructions on the LCD must be followed. The tools will re-engage and require re-initialization. The job will have to be restarted from the PC.

If something begins to go wrong during the cut, such as the stock moves unexpectedly, the operation can be paused by pressing any of the gray directional buttons on the console, or ‘ONLINE’. This takes the machine out of online mode, pauses the operation, and lifts the tool. The cut can be continued by pressing online once the issue is resolved.

Software

Online Mode

The Zund has two main modes of operation, online and offline, which are switched between by pressing the red ‘ON-LINE’ button at the bottom right of the console. Most setup operations are performed in offline mode, such as tool changes, parameter editing, and making changes to the file through either Cut Center or Cut Editor. Online mode is activated before performing any cuts, or entering Interactive Mode through Cut Center. Most common errors occur from not being in the correct mode, but are easily fixed by pressing the button and entering the correct mode.

Cut Queue

The Cut Queue lists jobs, both incomplete and completed. Order can be changed by clicking on a heading at the top of the list. We generally sort the list by date, to keep the newest jobs at the top of the queue.

Once a job is completed, it will be moved to the ‘Job done’ queue, under the ‘Job queue’. Files can be accessed the same way from either, by double clicking to open directly in Cut Center, or by selecting the ‘E’ icon to open directly in the Editor.

Cut Editor

The Cut Editor is used for making changes to the geometry of the file, including adding, deleting, moving and scaling vectors. In addition, the starting point and cut order of individual vectors can be specified if the auto-order the program assigned does not perform satisfactory cuts.

Bridging

The Cut Editor is also used to add bridges to routing jobs to ensure the cut out features are not pulled up by the dust extraction, which will ruin the job and risks damage to the bit and router.

A routing file before and after bridging. Bridges are formed during the ‘Multi pass last depth’ parameter in the Cut Center ‘Machine step settings’ window, and should be .02 at a minimum to ensure strong bridges.

Setting order/direction/starting point of a vector

If a corner or feature of your geometry is getting caught and dragged by the blade, the order and direction of each line can be altered by first selecting the view order and view direction icons. The most common cause of corners being dragged is when the blade approaches an acute angle that has already been cut previously. The tip is unsupported, and if the blade is moving too quickly, it will catch and be dragged along with the blade. This is most damaging in foamcore, where the paper tears away and the foam interior balls up.

Example of a risky cut. Moving from the center-out increases the risk of the edges being torn, and an example of a safer cut, cutting from areas with more mass inwards.

Pink arrows denote open contours while the light teal arrow (upper right corner) indicates closed contours.

By selecting ‘Reverse direction’ through Tools –> Reverse direction, the editor enters a mode where every time a line is clicked, its direction reverses, denoted by the small pink arrow at the starting point of the line. This is most useful in situations where the blade approaches thin or acute features and ends up deforming or dragging them. By traveling outwards from the center of mass, the sharp corners are preserved.

By selecting ‘Interactive order’, the order of each line can be set by clicking on each line in the desired order.

Adjusting geometry

Precise adjustments to geometry is made using the ‘Numerical geometry’ window, accessed by highlighting the geometry to be edited and right clicking.

Numerical geometry can be used to move, scale, and rotate geometry by specific values. The boxes in the upper right select whether the geometry will be moved/scaled from the center, or a specified corner.

Any operation more complex, especially adding geometry, should be performed in the original program, at the Cut Editor lacks most of the features that make changes accurate, such as snap-to fuctionality.

Fills

When using the engraving tool to remove material from within an enclosed area, a toolpath needs to be generated in this area, otherwise the router will only engrave along the perimeter of the shape. There are two methods of filling available, Island fill and Hatch fill. Island fill offsets from the outer border repeatedly until the shape is filled, while Hatch fill creates a series of parallel lines within the border, either horizontally, vertically, or at a specific angle. Bit size and overlap percentage must be set correctly in Cut Editor in order to achieve the desired result when cutting. If a different-sized tool is used to cut the material than is specified when creating the fill in Cut Editor, then damage may be caused to the bit, material may not be completely removed from the area, or too much material will be removed at the perimeter of the area specified.

Cut Center

The main program used for performing cuts. Cut Center allows for assigning operation methods to layers (steps) if not completed previously, and adjust settings such as which tool and blade are being used. The Cut Center also allows for adjusting offset from the origin, performing test cuts, and adjusting and testing the vacuum.

The main icon toolbar in Cut Center with the most commonly used icons labeled.

Some icons, such as ‘Interactive Mode’ are only available when the machine is in ‘Online’ mode and will be grayed out unless in the correct mode.

To change a layers operation parameters, double click on the layer to open the ‘Machine step settings’ window. The ‘Method’ drop down changes machining operation type. The tool and blade drop downs change the tool to be used for the operation from a preset list of available tools. In general there are usually only one or two blades and available tools per method per material, to ensure the best tool is being used. If the tools installed the machine do not match any of the listed tool for the operation, a tool change must be performed.

Setting a reference point

When not referencing off of the borders of stock or to registration dots, a reference point must be set. Reference points are most often used when using irregular or scrap pieces of stock where there are no clean edges to reference off of and registration dots have not been built into the model. This point can be anywhere on the table, and will move the jobs origin point to the set reference point.

To set a reference point:

Check the machine is in ‘Online’ mode.
Select the ‘Interactive mode’ icon.
Use the arrow keys to navigate the laser pointer over the desired reference point.
Right click and select ‘Set reference point’.
To ensure the cut will not go off the edge of the material, run a simulation by selecting the ‘Simulation’ icon and then ‘Laserpoint simulation’
The laser will then trace out every cut that will be performed during the job. Watch to make sure it stays within the boundaries of the stock at all times.

Vacuum settings

There are two main settings for the vacuum hold down: Vacuum width and vacuum strength. Vacuum strength is specified on a slider from 1-10 by selecting the ‘Vacuum strength’ icon. Vacuum width is the width of active vacuum hold down along the y axis of the table and is denoted by the dashed yellow line on the screen. Vacuum zones run from the set width on the y axis, starting from the right side, all the way to the back of the table. The vacuum can not be adjusted front to back along the x axis, but unused space should be covered with cardboard or scrap to increase the hold down under the stock. To adjust the width, right click the table and select ‘Set vacuum width’. Test the vacuum after adjusting the width to ensure the full width of the stock is held down.

‘Machine step settings’ windows before assigning an operation, for a Thru-cut operation, and a routing operation.

Adjustable operation parameters

Method: The type of operation to be performed. Each material has a set of available operations depending on its characteristics.
Name: What the layer will appear as on the right hand side of the screen.
Color: The color the layer will render as on the screen.
Line type: Whether the operation will perform along a solid, dotted, or dashed line.
Cutting mode: Always set to standard.
Tool selection: Drop down menu will allow the selection of the tool to be used during the operation, if multiple are allowed.
Tool insert selection: Select the tool insert (blade or bit) to be used during the operation.
Initialization: Where the tool will register height from. Alway set to base.
Clearing distance: How high above the top of the material the tool will retract to travel. Does not need to be adjusted from default.
Material thickness: Current thickness of the material. Cannot be altered through this window, needs to be set in the material selection window.
Base depth: How deep relative to the table the material will cut. Should never be more than +/-.005. Adjust in small increments (+/-.002) if blade is not cutting all the way through the stock.
Multi. pass max. depth: The most stepdown the router will perform on a single layer. Should not exceed .0500in.
Multi. pass last depth: The depth of the final routing layer. If using bridges, should be at least .0200in, as bridges are formed from this layer.
Machining depth: The specified depth for engraving operations.
Score depth: The specified depth of a score, either in inches or percentage of material thickness.
Acceleration, tool lowered: The maximum acceleration the tool will travel while cutting the material, from 1-4.
Speed, tool lowered: The maximum speed the tool will travel while cutting the material. Slow down for a cleaner cut in most materials.
Knife compensation: Offsets the cut to compensate for the thickness of the blade (generally unnecessary).
Speed, lowering tool: The speed a tool will lower between steps. Must be >5in/s for routing operations.
Router speed: Speed the bit will spin during routing operations. Should not be adjusted.

Orange parameter boxes signify that the setting has been changed from the default.

On the right side of the window is a representation of the current stock thickness next to a representation of the specified cutting depth. The red line on the routing operation represents the thickness of the Sealgrip underlay. The alternating light and dark gray rectangles represent the number and depth of each multi pass step to be performed. The green line above the material is the clearing distance.

Advanced settings

The second tab lists advanced cut settings. These should never be adjusted, with the exception of Overcut, if less or more overcut is desired during a cutting operation.

Overcut defines the offset from the original start and stop point of each vector. Some knives, particularly wider geometry knives and the DRT rotary blade create a significant amount of overcut. When cutting out thin features, this overcut can unintentionally cut completely through those features.

Some overcut is inevitable when using thicker materials, such as foamcore, and if pristine cuts are required, the file should be set up to use the bottom side of the foamcore as the clean side, as that side experiences much less overcut than the top side.

Red tool labels and red ‘Start job’ button in Cut Center indicated that the tool specified by an operation is not currently installed in the machine and will required a tool change.

Step-by-step Instructions

Cutting/Scoring/Drawing

Construct geometry using Illustrator, AutoCAD, Rhino, Revit, or any other program that will allow for export to a vector format
1. When using Rhino, be sure to export using a 1:1 model scale and not viewport boundary
2. Import to Illustrator to check cleanliness of files (floating control points, ensuring closed shapes have no gaps)
Save file to as an AI, EPS, DXF or HPGL vector file.
Submit job to App to reserve time, or save files to ZUNDTMP, for walk-up use.
Go to the CNC room (L33) where the Zund is located.
Import the file into Cut Editor, assign methods and material, and then send to server.
Double click the file in the job list to open in Cut Center. If edits need to be made, the file can be opened again in Cut Editor by selecting the small red ‘E’ icon. The editor can also be accessed through the Cut Center.
If the operation steps have not been specified through layer names, double click the machining step layers located on the right of the screen to assign a method, tool, and blade.
If the specified tools and blades are installed in the Zund, the labels under the images of the tool and blade at the bottom right of the screen will all be green. If the tool is not correctly loaded, or the tool was changed through the ‘Machine step settings’ window, one or both of the labels will be red.
If a blade or tool was changed through the ‘Machine step settings’ window to a tool that is loaded in the machine, and the labels are still red, double click the red label to open a window prompting an initialization before job start. This will initialize and scan the tool before performing the cut to ensure the z height of the tool is accurate.
If the loaded tools are not included in any options through the ‘Machine step settings’ window, a tool change must be performed to install the proper tool.
After the tools are loaded, jog the cutter head gantry to the back of the table to load the stock onto the table.
1. In Cut Center, select the ‘Interactive Mode’ icon to directly control the gantry and move it to the back of the table using either the arrow keys or clicking on the screen.
2. On the physical console, the gantry can be controlled by pressing the gray buttons at the bottom of the control panel in the direction of travel, holding the center button to move faster.
Load the material onto the table, within the marked yellow lines which represent the maximum cutting size.
Test vacuum hold down by selecting the ‘Vacuum on/off’ icon.
Try to push the stock. If it moves, increase the vacuum power using the slider next to the ‘Vacuum on/off’ icon.
The vacuum width can also be set by right clicking on the desired width on the screen and selecting ‘Set vacuum width’. Narrowing the width to the stock increases the vacuum power to the relevant areas.
Once the stock is secure and all the correct tools are loaded, the Zund is ready to begin the cut.
In general, the order of operations should be Register -> Draw -> Score -> Cut for best results.
Select ‘Start Job’ to initialize registration. Use the arrow keys to navigate the camera to the right edge of the stock if using border registration. Once a green line appears over the image, hit enter or register to scan the right edge. Do the same with the bottom edge to complete initialization and begin the cut.
1. If using ‘best fit’ (dots) registration, first be sure that the marked out areas on your stock match the marks on the file exactly. Then, apply a ‘ring’ decal (located near the white board) over the mark on your stock. ‘Best fit’ by default looks for rings with an inner diameter of .25″ and an outer diameter of .5″, but these settings can be adjusted for special cases. Once the decals are applied accurately, begin the job and maneuver the camera over the ring. A green circle should appear over the inner circle of the decal. If one does not, or the green circle flickers, right click on the camera feed to adjust brightness, contrast, or lighting settings until the green ring is constant. Register, and continue until all dots are scanned. The job should begin normally after registration is complete.

Performing a Test Cut

To verify the settings and check the quality of cut, test cuts should be performed.

Enter ‘Interactive Mode’ and move the laser pointer to an open part of your stock that does not have geometry.
Right click on the screen and select ‘Set reference point’ to select the point on the stock that the test cut will be performed on.
Right click on the screen and select ‘Test cut rectangle’, then mouse over the layer operation option to perform the test cut on (Thru Cut, Score, Engrave, etc)
Mouse over and select ‘Rectangle – 1×1’ to test cut a 1″x1″ rectangle with the chosen settings.
The Zund will immediately move to the set reference point and cut a 1″x1″ rectangle.
Inspect the cut and adjust base height if it is either not cutting through or cutting through too deeply, or speed if it is not cutting cleanly enough.

Examples of Proper Cutting Depth

Example of proper cutting depth – Lines should be barely visible.

Example of too deep cutting depth – Easily visible and will catch fingernail if you gently run your nail over the table. Subtract from the base depth until lines are no longer clearly visible.

Example of DRT TPU/Fabric cutting – Depth is fine but the tool (mostly the DRT) forced or melted part of the fiber or material into the fibers of the table. It will look as though the table is deeply cut, but should not be deeper than a proper cut. Closely inspect to ensure that it is just material remnants bonded to the fibers and not a too deep cut.

Routing/Engraving

Once the router module is installed, screwed in and initialized, perform the same steps listed above to specify each steps machining operation.
When routing through stock, especially with smaller parts (<6″), it is imperative to add bridging to the file to prevent small parts being sucked up by the dust extraction, which will ruin the part and potentially damage the bit and router module.
To ‘carve out’ engraved sections, select the closed shapes to be engraved and select either ‘Hatch Fill’ or ‘Island Fill’ to convert the outline into a filled area. If you are unable to engrave a shape, it is likely the shape is not a closed polygon, especially when exporting from AutoCAD or Rhino. Check your file in Illustrator to ensure all polygons are closed with no overlapping lines or open control points.
1. To add bridges, open the file in Cut Editor, select all of the parts by dragging to highlight or pressing Ctrl+A.
2. Under ‘Tools’, mouse over the ‘Bridges’ option and select ‘Auto Bridging’ to automatically add bridges to the part, or ‘Insert’ to manually place bridges around the parts.
3. There should be no less than three bridges per piece, spaced out such that the bridges are attached to part of the material that will not be cut away, and the piece being cut is held securely and can not move easily
Specify the desired engraving depth in the ‘Machine step settings’ window for each engraving layer.
Set engraving operations before routing operations.
Safety glasses must be worn before any routing operation.
Turn on the router module by pressing the power button surrounded by a buzz-saw on the control panel.
Sealgrip underlay must be used during any and all routing operations. Ensure the Sealgrip is laid flat and aligned to the edges of the table without excessive chips on the surface that may throw off the flatness of the stock going on top of it.
Load your stock on top of the Sealgrip. Use as much Sealgrip is as needed to fully support the stock. No corners of the stock should overhang the Sealgrip.
Before beginning the job, check over the operation parameters to ensure the cut will not damage the tools or materials.
1. ‘Multi pass max depth’ is the maximum stepdown the tool will perform during the job. Especially in harder materials, this should never be more than .025 in harder metals and .05 in softer plastics.
2. ‘Multi pass last depth’ is the final step of the operation, and will determine the thickness of the bridges. This should always be at least .015.
3. ‘Speed – tool lowered’ is the speed the bit will travel through the material. This should be no more than 5 in very soft materials and no more than 1.5 in harder materials and metals.
4. If you are unsure of your cut settings, clear your job with a trained TA to have them look over your job and approve or alter settings.
Once the parameters are set and the stock is loaded on top of the Sealgrip, test the vacuum hold down to check that the material will not shift. Adjust vacuum strength if the stock can move.
Be sure everyone around the table is wearing safety glasses and inform the CNC TA’s that there will be routing in case they want to seek out hearing protection
Start the job. Before starting a new routing operation, you will be prompted to select if an underlay is being used. Select Sealgrip and approve.
The job will start. Register the borders of the stock and carefully observe the cut. If the router seems like it is cutting too deeply, moving too quickly, or making abnormal sounds, stop the cut immediately and review the cut parameters with a TA to ensure safety.
Constantly monitor all routing operations. If there are unexpected noises, excess chips not being picked up by the dust collection, or pieces being sucked up due to insufficient bridging, immediately stop the routing operation using either the gray directional keys on the console or hitting any of the four emergency stop buttons and review the settings and bridges with a trained TA.
The table must be vacuumed after each routing/engraving operation to clear all material chips left by the router. Chips on the table can cause future material laid on the table to be un-level, throwing off the precision of routing and engraving operations. Harder materials, such as aluminum, can leave chips behind that can embed themselves into the fabric of the table if not cleaned up after the cut. There is a dedicated vacuum attachment that runs off the same shop vac that provides dust collection located near the shop vac on the right side of the table. To switch the shop vac over to use this attachment:
1. Unplug the power cord located near the back right bottom corner of the machine.
2. Remove the attached hose from the shop vac.
3. Insert the hose attached to the table vacuum attachment into the shop vac.
4. Plug the power cord into a wall outlet. The vacuum will immediately turn on and be ready for use.
5. When the table is vacuumed clean, immediately replace the original hose into the shop vac and return the plug to the extension coming from under the machine. (If the hose and power cord are not returned to their original configuration, the shop vac will not turn on during routing operations and will not remove chips, which can bind the bit.)

Troubleshooting

Knife isn’t cutting all the way through
1. Adjust the base depth by adding .002 to the base depth at a time (adding a positive number lowers the base depth to cut deeper, adding negative numbers raise the base depth and cuts more shallowly.) Please observe a MAXIMUM base depth of 0.01″. This value should NEVER be exceeded.
Knife still isn’t cutting all the way through, the cut is rough, or the blade caught and dragged parts of the stock
1. Lower the ‘Speed – tool lowered’ parameter to make the blade move more slowly through the stock, this is often necessary when oscillating tools “perforate” but do not make a continuous cut.
Knife still isn’t cutting through after reaching 0.01″ base depth
1. Cut from both sides of the material (use the “flip” job template). This works well in 1/8″ chipboard with a deep score (80%+) on the top and a thru cut on flip (back). A sharp blade is also essential, and the T6 does work well as long as it is sharp. The Z16/17 are carbide and good choices, as well as the Z10 but the heavier blade may require more force to make the cut.
2. Inspect the tip of the blade. It may be damaged or chipped. If it is damaged, make note of it to a TA and perform a blade change with them.
Excessive over-cut on the top surface
1. Ask a TA whether using a thinner blade geometry is appropriate for the current material and thickness. If it is, perform a blade change and use the thinner blade.
2. Cut from both sides of the material, just beyond half-way from either side.
My material is moving around under the blade/tearout is happening
1. For thin materials such as paper, it is important to maximize vacuum power by covering as much as the table as possible with scrap material. The more holes there are cut into a material, the weaker the vacuum force will be since air will be able to escape through the cuts.
2. If the file contains a large number of cuts close together, it may help to specify the order and direction of the cuts to ensure the cuts generally move outwards from the center, and avoid cuts approaching acute angles, as these are mostly likely to get caught and dragged by the blade. The exact optimal order and direction of cuts is geometry dependent, and will vary from cut to cut. To specify the order and direction of cuts, open the file in Cut Editor, then select these icons to show the order and direction of the cuts.
  1. To adjust the direction of the cuts, mouse over ‘Tools’ in the toolbar and select ‘Reverse direction’. With this tool selected, every line that is selected will have its start and end point swapped, which is denoted by the direction of the small pink arrow.
  2. To adjust the order, select the ‘Interactive order’ tool and click the lines in the order that is desired.
  3. To split lines into smaller lines, to force the tool to lift up and avoid delicate corners, mouse over ‘Objects’, then ‘Points – Create’ to add points at whichever point along the line that the split should occur. Then, right click on the line and select ‘Split contour’ to split the line at all points on the line, or to break up closed polygons into their component lines.
3. Try adding the spring loaded “glide shoe” using the appropriate length (8mm or 12mm) to help hold down the material while cutting. The 8mm can be used on the UCT and the 12mm on the EOT.
The computer logged off in the middle of my cut and the job stopped
1. Either log back in, and select continue job, or simply press the ‘Online’ button on the console to continue your job. If you select exit or redo, the current place in the job will be lost and the job will have to be restarted.
The knife isn’t lowering down to my material/cutting at the wrong height
1. Check the entered material thickness and ensure that it is accurate. ~~Some hotfolders for commonly used materials have preprogrammed thicknesses, but most materials have a range of accepted thicknesses that must be entered correctly to cut properly.~~
The file is rotated incorrectly in relation to the table.
1. Click the blue ‘Rotate’ arrow in Cut Center to rotate the file 90 degrees. The file can also be flipped horizontally and vertically to be accurate to the table and stock.
The blade is damaging the edge of my material while trying to cut it.
1. If you have your stock modeled in material and intend to use the stock edge of the material, it can be helpful to select and delete the lines on the file representing the edges of the material so that the cutter skips over them, leaving you with the factory edge. Cutting directly on the edge generally will ball up softer materials, especially foamcore, as the edges are unsupported by surrounding material.
My material keeps lifting in the middle of cuts around my parts.
1. Very warped materials, especially foamcore and veneer, are constantly trying to return to their original shape. The vacuum table is effective at holding down large contiguous sheets, but the more holes are made in the material, like during cutting operations, the less the vacuum force can resist the bending force from the warp. When cutting these materials, avoid grouping the parts tightly together, as this leaves less material between the parts for the vacuum to hold down. In general, the more spread out parts are on a sheet, the better held to the table they will be.
2. Try adding the spring loaded “glide shoe” using the appropriate length (8mm or 12mm) to help hold down the material while cutting. The 8mm can be used on the UCT and the 12mm on the EOT.
3. If you are routing, make sure to add bridges and make sure the thickness is adequate to survive the mulit-pass step downs. Thin material (like 0.5mm/0.019″ inch aluminum sheet) can be very problematic and should probably not be cut on the Zund. It will move around ad spring up as tension is released. Minimum thickness is probably more like 1/32″ or 0.0312″, perhaps 1mm to be successful.
There is no “Start Job” button in Cut Center. (and/or) The Tools images in Cut Center don’t match what is in the machine.
1. Close all open windows of Cut Center, relaunch the file you intend to cut from Cut Queue.
2. (Explanation: Only the “active” instance of Cut Center is able to send jobs to the machine. It’s not seemingly possible to designate which window should be the “active” instance, but it seems like it defaults to the first window of Cut Center that is opened, so any subsequent windows cannot be made “active” without closing all and re-launching.)

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