CNC & Laser Cutting
We typically have parts manufactured by a sponsor or a parent's workplace rather than operating machines ourselves. That means the most important skill for our team is knowing how to prepare and export files correctly so the parts come back right.
When to use which
Laser cutting
Aluminum sheet/plate, steel sheet
Flat parts with complex profiles. Fast, precise, and handles fine details well.
Holes/cutouts at least 50% of material thickness
Waterjet
Aluminum, steel, polycarbonate, almost anything
Same as laser but can cut thicker material and materials that don't laser well. Slightly less precise than laser.
Holes/cutouts no less than 0.070"
CNC routing
Polycarbonate, aluminum (with the right setup), wood, plastics
Flat parts, pocketing (variable depth cuts), and materials that can't be laser cut like polycarbonate.
Holes/cutouts no less than 0.125". Inside corner radius limited by bit diameter.
Polycarbonate cannot be laser cut. Laser cutting polycarbonate produces toxic fumes and a poor edge finish. If you have polycarb parts, they need to go on a CNC router or be hand-cut.
What determines which method you use
For most flat aluminum parts (plates, gussets, bellypan, brackets), laser cutting is the default. It's fast, precise, and services like SendCutSend make it easy to order.
Use CNC routing when you need variable-depth cuts (like pocketing to save weight without cutting all the way through), when the part is polycarbonate, or when inside corners need to be sharp (though you can add dog-bone reliefs to laser cut parts instead).
Use waterjet when the sponsor or service has one available and the material is too thick for laser or can't be laser cut.
Preparing parts in Onshape
The goal is to give the manufacturer a clean 2D file that represents exactly what needs to be cut. For flat parts that don't need variable depth, this means a DXF. For parts that do need 3D information (pocketing, chamfers, counterbores), this means a STEP file.
Use this for any part that gets cut all the way through with no variable depth. This covers most laser cut and waterjet parts.
Steps:
In your Part Studio, click the flat face of the part you want to export
Right-click that face and select "Export as DXF/DWG..."
In the export dialog, set:
Click Export and save the file
What to check before sending:
Open the DXF in a free viewer (like eDrawings or an online DXF viewer) to make sure it looks correct and nothing is missing
Verify the dimensions match your Onshape model (occasionally export scaling can be off)
Make sure all holes and internal cutouts are present in the export
Confirm units match what the manufacturer expects (inches vs. mm)
Use this for any part that has variable depth features like pocketing, counterbores, or chamfers that the CNC needs to machine. Also use STEP when sending parts to a machine shop that prefers working from 3D models.
Steps:
In your Part Studio, right-click the part in the parts list on the left
Select "Export..."
In the export dialog, set:
Format: STEP
Click Export and save the file
What to check before sending:
Open the STEP file in a free viewer to verify the 3D geometry is correct
Make sure the part includes all features (pockets, counterbores, holes)
Include a drawing with critical dimensions if any tolerances matter (bearing holes, shaft spacing)
Even when you send a DXF or STEP, it's often helpful to include a 2D drawing with key dimensions called out, especially for parts with tight tolerances.
Steps:
Create a new Drawing in Onshape from the part
Add the views you need (typically a top view for flat parts)
Dimension any features that have specific tolerance requirements (bearing holes, shaft center-to-center distances)
Export the Drawing as PDF for the manufacturer to reference alongside the DXF or STEP file
Not really needed for Can Lines Engineering but could be helpful when pocketing is needed.
Design tips for manufactured parts
These apply regardless of whether the parts are laser cut, waterjet, or CNC routed.
Avoid sharp inside corners on CNC parts
The router bit is round, so it can't cut a perfectly sharp 90 degree inside corner. Add a dog-bone relief (a small circle at the corner) or a fillet to the design.
Design clearance holes, not exact-fit holes
For bolt holes, make them slightly oversized (0.015" to 0.020" larger than the bolt). Bearing holes are the exception and should match vendor specs exactly.
Pocket for weight savings
If a part is thicker than it needs to be structurally, CNC pocketing can remove material to save weight without making the part thinner everywhere.
Sending to Can Lines Engineering
Can Lines Engineering is where Diego Salcedo's dad works. They have graciously offered to cut parts in the past (namely 2023, 2024, 2025, and 2026 season). Although no official partnership is set in stone, please ensure that they know they are cutting parts in advance!
If getting parts cut at Can Lines, the only machining services are laser cutting for metals and CNC routing for polycarbonate! They do not cut metals on the router and do not cut plastics on the laser cutter.
Send early. Normal turnaround is about 5 to 7 days, but this can greatly fluctuate depending on the amount of work they get. Get your designs finalized and submitted by end of week 2 if possible.
Double check your DXF before submitting. A wrong export or a missing hole means waiting another week for corrected parts. Open the file in a viewer, verify dimensions, and compare it to your Onshape model before you hit send.
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