Material Cutting
Overview
This tutorial will give you some insights into the things we have learned about cutting various materials and thicknesses, tricks and reminders to better prepare the material before cutting.
Material Selection in Your Design
Material selection is a very important and large aspect of design whether for an engineering or craft application. WAM provides a continually expanding material database, however it is a finite number of materials and thicknesses.
For materials or thicknesses that are not in our database we provide a set of instructions that will show you how to obtain the cutting parameters for your own material database entry. Take this into consideration when selecting a material for your design.
Sourcing Material / Laying Out Your Design in WAM
For the most common materials, McMaster Carr and Online Metals provide fast service with many thickness options.
Remember that WAZER can only cut 12”x 18” extents and can only fit 13” x 19” materials, so anything larger than this will not fit.
Craft materials such as stained glasses or ceramic tile have much more variability in thickness across a sheet than engineering material such as metals, composites, and plastics. This means that the advertised thickness of say 3mm could have thicknesses of 2.5mm-3.5mm across the sheet mainly due to the manufacturing process that it was created from.
Craft materials such as ceramic tile are typically advertised in the nominal size of ⅜” however the actual thickness is typically close to but not ⅜”.
When importing your design into WAM you may want to take into consideration the location and orientation in which you place your design onto the virtual cut bed. These considerations will help you to minimize the amount of unused material or “off cut” and is especially true for new large sheets.
Fixturing Material
Fastener Location/Torque
Generally, you want to use the fasteners that arrived with your WAZER to secure your material onto the bed.
The location of the fasteners are important as you want to ensure that the no part of the screw is in the cutting path or else your cut could be compromised.
The amount of torque with which you screw down the fastener is also important as you want to ensure your material is fixed in place but is not under significant compression.
Brittle Materials
When fixturing brittle materials, such as glass or ceramics, more care needs to be taken when tightening down the screw since the material is susceptible to cracking and breaking. Too much torque will result in a damaged piece or potentially ruining a cut by cutting with material that is now free to move.
Soft/Thin Materials
Soft and or thin materials have a tendency to deform in the locations of the fasteners so taking care not to apply too much torque in these areas is critical, especially if you are cutting close to the edges of your material.
These materials also have a tendency to flop up and down due to some of the jet stream reflecting off of the cut bed. To solve this problem you can cut a window profile out of more rigid material such as aluminum. This window profile would be placed on top of your soft/thin material and then the fasteners would be torqued down on the rigid window. This allows for a more even spread of force across the bottom material and prevents the material from moving around.
Uneven Materials
Some materials may not be perfectly flat and are too thick or too rigid to bend flat. In this case, you must take extra caution or avoid cutting these materials as this presents an opportunity for the Nozzle to hit the material or cause a backflow into abrasive line — either could result in a lost cut.
We recommend moving the Nozzle around the material along with the touch off tool to make sure there is clearance at all points. Set the Nozzle height off the highest point and then reduce the speed slightly to compensate for the slightly high Nozzle height in the lower parts of the material.
Permanent Fixturing
If you need to locate an edge of your material with respect to the location of the cut and will be doing it repeatedly, it is probably to your benefit to create a permanent fixture. This will allow you to quickly push your cut material up against and fasten down without having to determine where to place the cut material every cycle. If you do this, make sure that your fixture thickness is less than the cut material thickness so that the Nozzle does not become jammed.
Material Types
Working With Metals
Consistent thickness across metal sheeting results in more consistent edge quality than less consistent materials.
More accurate thickness in sheet meaning that nominal thickness is very close to actual thickness. This translates to better selection of parameters in the WAM database and better optimization for cutting than less accurate materials.
Metals are typically easy to fixture since they are mostly rigid.
Hard, stiff metals that are not perfectly flat should be taken with caution when trying to cut as your material will not be perfectly flat on the cutting bed and could result in the Nozzle jamming or abrasive line becoming clogged.
Working With Glass and Ceramics
Varying thickness across the sheet results in less accuracy. For example, the advertised thickness of say 3mm could have thicknesses of 2.5mm-3.5mm across the sheet, mainly due to the manufacturing process that it was created from.
Glass and Ceramics tend to be more brittle, therefor prone to cracking and breaking while fixturing.
Tendency to chip around the cut area leads to larger kerfs.
Working with Plastics
Plastics can more easily clog the filters.
Expect “burrs” to be “gummy”.
Larger thicknesses will show worsening edge surface finish because the material is soft.
Working With Rubber
Can more easily clog the filters.
Larger thicknesses will show worsening edge surface finish because the material is soft.
Need some type of rigid material to fixture down thinner thicknesses.
Working With Composites
Delamination is a common failure for many composite and laminate materials. Often delamination between layers will occur at pierce locations due to the internal stresses induced by the pierce event. Currently, there isn’t a good feature built into WAZER to minimize this. However, we do find that higher quality/density laminates can work well on WAZER. For example DragonPlate carbon fiber has cut very well for us.
Material Thickness
On particularly thick material you will need to do some planning for the cutting draft. The effect of this and what you can do with it varies by the material.
Additionally, very thick materials and tight inside corners can produce results that may not be acceptable for some. In these cases, it is recommended to undersize and manually finish the edge.