SendCutSend Community College is a step-by-step video series designed to teach computer-aided design (CAD) from the very beginning. Whether you’ve never opened a CAD program or you’ve dabbled and want a structured path, this series will guide you from the basics to designing real, manufacturable parts you can bring to life with SendCutSend’s cutting and finishing services.
You can access all lessons on our website sendcutsend.com/education and on YouTube.
If you haven’t gone through previous chapters, you’ll want to start there before jumping into Chapter 5. Here’s what you can expect in this Chapter.
Chapter 5: From CAD to Cut – Designing for Sheet Metal
Lesson 1: From CAD to Cut – Designing for Sheet Metal
In the first lesson of chapter 5, Jake introduces key terms and concepts you need to understand how different cutting processes work, helping you design parts that cut cleanly and accurately. He explains what’s happening behind the scenes when materials are laser cut, waterjet cut, or CNC machined, and how these processes influence your part’s final quality and precision.
Jake breaks down essential terms like kerf (the width of the cut), kerf offset, pierce, lead-in, burr, and heat-affected zone (HAZ), explaining how each impacts your part’s edges, tolerances, and surface finish. He also compares cutting methods:
- Fiber laser cutting uses heat and gas to cut metals quickly and precisely, with minimal heat effects.
- Waterjet cutting uses high-pressure water and abrasive material, producing no heat but a wider kerf.
- CNC routing removes material with rotating tools, creating clean perpendicular edges but requiring different offsets.
By understanding how each cutting process works, you’ll be able to design parts that align with real-world manufacturing limits and achieve consistent results.
What you’ll learn:
- The key terms used in cutting processes: kerf, offset, pierce, lead-in, burr, and HAZ
- How fiber lasers, waterjets, and CNC routers cut materials differently
- Why kerf and offset affect your part’s accuracy and dimensions
- How material thickness and hardness influence burrs and edge quality
- Why understanding cutting mechanics helps you design better for manufacturing
Lesson 2: How to Design Parts That Pass DFM
In chapter 5 lesson 2, Jake explains how the cutting process impacts your part’s geometry and what design rules help keep your parts manufacturable. Building on the previous lesson about how lasers and routers cut material, he focuses on how heat, energy, and tool size determine the minimum features your design can have.
Jake reviews important concepts like kerf and heat-affected zone, then introduces two new terms: hole-to-edge distance and bridge distance. These define how close holes, slots, and edges can be before heat or tool pressure causes distortion or burnout, similar to blowing a fuse. He explains how SendCutSend determines safe minimums for these features through real-world testing and provides a simple rule of thumb:
- Keep holes and bridge gaps at least 50% of the material thickness for reliable results.
Jake also touches on floating geometry (like the centers of letters “O” or “A”) and how to use bridges to hold these features, as well as warping, which can occur when too much material is removed.
By understanding these limits, you’ll design parts that cut cleanly, stay flat, and pass DFM checks without revision.
What you’ll learn:
- How cutting affects part geometry and feature size
- The meaning and importance of kerf, heat-affected zone, hole-to-edge, and bridge distance
- Simple design rules for minimum holes and bridge gaps
- How SendCutSend determines DFM-safe dimensions
- When to reference material-specific guidelines for accuracy
- How floating geometry and warping occur and how to avoid them
Lesson 3: How to Avoid Tolerance Mistakes in CAD
In chapter 5 lesson 3, Jake explains how the cutting process affects tolerances, the small but important differences between your CAD model and real-world parts. He breaks down what tolerancing means, where variation comes from, and how it impacts both single parts and assemblies.
Jake begins by defining tolerance as the allowable range a dimension can vary from its nominal value, showing how machine movement, temperature, and setup can all affect part accuracy. He then introduces tolerance stacking, where small variations in multiple features or parts add up, potentially causing alignment issues in assemblies. Using examples, he demonstrates how to properly dimension from a common origin to avoid compounding errors.
He also explains how kerf taper, multiple machining operations, and tabs or workholding features contribute to real-world deviation from perfect CAD geometry. By understanding and designing with these tolerances in mind, you can ensure your parts fit together correctly, even after manufacturing variations occur.
What you’ll learn:
- What tolerancing is and why it matters in manufacturing
- How real-world factors like machine setup and temperature affect accuracy
- The concept of tolerance stacking and how to avoid it
- How to correctly dimension from a common origin for consistent results
- Why tighter tolerances increase cost and complexity
- How kerf, multiple operations, and workholding influence final part fit
- How to design and dimension parts that assemble correctly every time
Lesson 4: How to Avoid Tolerance Mistakes in CAD
In chapter 5 lesson 4, Jake introduces the fundamentals of sheet metal bending and the key terminology you need to understand before designing bent parts. He explains how bending is far more complex than just folding metal, it involves stretching, compression, and precise geometry that must be accounted for in your CAD design.
Jake walks through important bending terms like apex, bend angle, setback, flange length, material thickness, bend radius, and centerline, explaining how each one is measured and how it affects your final part. He also introduces the concept of the adjusted centerline and the K-factor, which describe how material stretches and thins during bending, critical for getting accurate flange lengths.
By understanding these terms, you’ll know exactly how to measure and define your bends so your designs come out right the first time. Jake also points to SendCutSend’s downloadable K-factor charts and sheet metal rules for Fusion and SolidWorks, along with a bend calculator to simplify setup and ensure accuracy.
What you’ll learn:
- The key terms used in the bending process and what each means
- How to measure bend angles, setbacks, and flange lengths correctly
- Why bend radius and material thickness affect the final shape
- How stretching and compression occur during bending
- What the K-factor is and why it’s critical for accurate CAD designs
- How to use SendCutSend’s bend calculator and sheet metal rule files for precise results
Additional resources:
Bending Guidelines
Autodesk Fusion downloadable gauge tables
Solidworks downloadable gauge tables
Lesson 5: How to Calculate Bend Allowance and Bend Deduction
In chapter 5 lesson 5, Jake dives into the two key calculations behind sheet metal bending: bend allowance and bend deduction. These formulas explain how metal stretches and compresses during bending and help you predict the final size of your parts accurately.
Jake revisits terms from the previous lesson, like bend radius, K-factor, and material thickness, and shows how each affects your part’s elongation and final flange length. He explains that bend allowance measures the true length of the material along the bend after forming, while bend deduction determines how much to remove from your flat pattern so the finished part bends to the correct dimensions.
He emphasizes that errors in these calculations can lead to incorrect flange lengths, hole misalignment, and parts that don’t fit as intended. Understanding and applying these relationships ensures that your bent parts match your CAD model in the real world.
What you’ll learn:
- The difference between bend allowance and bend deduction
- How to calculate and apply both in your CAD designs
- How bend radius, material thickness, and K-factor affect stretching
- Why accurate calculations prevent short or misaligned flanges
- How to predict real-world bend outcomes from your flat pattern
- How to design with precision so your bent parts come out exactly as intended
Additional resources:
Bending Guidelines
Bend Calculator
Lesson 6: How to Understand Bend Deformation
In chapter 5 lesson 6, Jake explains bend deformation, what happens to your part and its features during the bending process. While previous lessons covered bend allowance and deduction calculations, this one focuses on the physical effects of bending and how they impact surrounding geometry.
Jake breaks down how the punch and die interact, showing that successful bends require three points of contact. He explains why parts need a minimum flange length; if the flange is too short, it can fall into the die and cause a failed bend. He also introduces die marks (or witness marks), the small contact marks left by the punch and die, and discusses how friction and stretching in the bend area can lead to visible deformation.
You’ll also learn about feature distortion, such as holes or threads becoming stretched or oblong if they fall too close to the bend line. SendCutSend automatically detects and warns you about these issues during checkout, allowing you to approve or adjust your design before production.
What you’ll learn:
- What bend deformation is and why it matters in design
- How punch and die contact affects part shape and surface finish
- Why minimum flange length is critical for successful bending
- What causes die marks and how to account for them
- How friction and stretching affect nearby features
- Why features near bends can distort and how SendCutSend warns you in checkout
- How to design features safely outside the deformation zone for clean, accurate bends
Lesson 7: How to Add Bend Reliefs to Your Design
In chapter 5 lesson 7, Jake explains bend relief, why it’s necessary, where it goes, and how to design it properly to prevent cracking, tearing, and deformation during bending. While earlier lessons focused on bend calculations and deformation, this one dives into the practical design fixes that make your parts stronger and easier to manufacture.
Jake covers two key scenarios: standard bend reliefs (used when a flange doesn’t span the entire bend length) and corner reliefs (used when two bends meet). He explains how bending creates tension and stress risers that can lead to cracks over time, and how adding small relief slots or holes eliminates those problem areas.
He also shares rule-of-thumb dimensions for reliefs, making their width about 50% of material thickness, and their depth equal to the bend radius plus material thickness plus .020 inches—along with guidance for designing circular or square corner reliefs based on your material and application. Finally, Jake notes that most CAD programs like Fusion and SolidWorks can automatically add bend reliefs, but understanding the “why” behind them helps you make better design decisions.
What you’ll learn:
- Why proper bend relief design ensures cleaner bends and longer-lasting parts
- What bend reliefs are and why they’re critical for manufacturable designs
- How to prevent cracking, tearing, and stress risers in bent parts
- The difference between standard and corner bend reliefs
- Rule-of-thumb dimensions for relief width and depth
- When to use round vs. square corner reliefs
- How CAD software can automatically add bend reliefs
Lesson 8: How to Configure and Prepare Bends in CAD
In this hands-on lesson, Jake takes everything you’ve learned about bending and shows you exactly how to apply it inside CAD. Using Fusion’s sheet metal tools, he walks through setting up proper sheet metal components, applying SendCutSend’s sheet metal rules, and adjusting critical parameters like material thickness, bend radius, K-factor, and relief types.
You’ll see how to create and edit flanges, configure bend positions and flange heights, and automatically add bend and corner reliefs based on material and thickness. Jake also explains how to switch between material rules, edit sheet metal settings, and generate flat patterns or STEP files ready for SendCutSend upload.
The lesson wraps up with key design and manufacturing limits, including tonnage, angle restrictions, U-channel ratios, and why parallel edges are needed for accurate bending. By the end, you’ll know how to confidently configure, verify, and export bend-ready sheet metal parts that meet SendCutSend’s DFM standards.
What you’ll learn:
- How to design within bending limits for safe, manufacturable parts
- How to set up and configure sheet metal parts in CAD
- How to apply and edit SendCutSend’s preloaded material rules
- How to define accurate K-factors, bend radii, and material thicknesses
- How to add and customize bend and corner reliefs
- How to control flange height, bend direction, and position
- How to generate flat patterns or STEP files for manufacturing
Lesson 9: How to Design and Add Countersinks to Your Parts
In chapter 5 lesson 9, Jake introduces countersinking, a key secondary operation used to give your parts a clean, flush appearance while improving function and fit. You’ll learn what a countersink is, how it works, and how to design holes that properly accommodate flat-head screws without protruding above the surface.
Jake explains the difference between 82° (imperial) and 90° (metric) countersinks, the roles of major and minor diameters, and how SendCutSend automatically applies these standards during checkout. He also covers material and size limitations, including minimum part thickness and maximum part dimensions for countersinking, and which materials are compatible with the process.
Finally, you’ll see how to model a countersink in CAD, understand how hole resizing works within SendCutSend’s workflow, and what to expect from your finished parts, such as minor marks or residue from secondary machining.
What you’ll learn:
- What countersinking is and when to use it
- The difference between 82° and 90° countersinks
- How to design and size holes for flat-head hardware
- Material, size, and thickness limits for countersinking
- How SendCutSend automatically adjusts holes during checkout
- How to model and verify a countersink in your CAD design
Additional resources:
Countersinking Design Guidelines
The Benefits of Countersinking
Designing for Countersinking
Lesson 10: How to Master Dimple Design in Sheet Metal
In chapter 5 lesson 10, Jake breaks down everything you need to know about dimple forming, how to use it to make your parts stronger, lighter, and better looking. You’ll learn what dimples (or “speed holes”) actually do, how the forming process works using upper and lower dies, and what design rules you need to follow to make sure your parts come out perfect.
Jake walks through the three key design dimensions, the dimple tool outer diameter, the dimple major diameter, and the dimple hole size, and explains how these affect spacing, edge distance, and bend clearance. You’ll also learn the minimum distances required between dimples, bends, and part edges to avoid deformation or tooling collisions.
Finally, Jake shows how to design dimples correctly in CAD, check spacing visually, and import your flat DXF into SendCutSend to configure your dimples for production. By the end, you’ll know how to design dimples that add stiffness and style without adding weight, and how to make sure your design passes DFM checks the first time.
What you’ll learn:
- What dimple forming is and why it’s used to make parts stronger, lighter, and more rigid
- How the dimple forming process works using male and female dies
- The three key design measurements: tool outer diameter, dimple major diameter, and dimple hole size
- How to calculate and follow minimum spacing requirements between dimples, bends, and part edges
- Common design issues like deformation, bowing, and cupping, and how to avoid them
- How to set up and verify dimples in CAD before exporting your DXF
- How to configure dimples in SendCutSend’s checkout to ensure proper sizing and direction
Additional resources:
Dimple Guidelines
The Ultimate Guide to Dimples Dies
Lesson 11: How to Add Tapped Holes to Your Sheet Metal Parts
In chapter 5 lesson 11, you’ll learn how to design and prepare tapped holes, cut or formed internal threads that allow bolts or screws to fasten directly into your parts. Jake explains the difference between cut vs. formed threads, imperial vs. metric thread types, and how to choose the right thread pitch for your design.
You’ll also learn about thread engagement, why material thickness matters for reliable threads, and how SendCutSend automatically sizes and taps your holes during production. The lesson walks through setting up tapped holes in CAD, understanding UNC/UNF and metric designations, and knowing when tapping is the best choice versus using installed hardware.
By the end, you’ll know how to confidently design and order parts with properly threaded holes, ready to assemble right out of the box.
What you’ll learn:
- How tapping creates internal threads for bolts and screws
- The difference between cut and formed threads
- When to use UNC, UNF, or metric thread types
- How thread pitch and thread engagement affect strength
- Why material thickness determines if tapping is possible
- How SendCutSend automatically resizes and taps your holes
- How to set up and configure tapped holes correctly in CAD
- When to choose tapping versus hardware installation
Additional resources:
Tapping Guidelines
Guide to Designing for Tapping
How to Measure Thread Size
Lesson 12: How to Add Insert Hardware to Your Sheet Metal Designs
In Chapter 5 Lesson 12, you’ll learn how to use insert, or “press-in,” hardware as a strong and reliable alternative to threading thin sheet metal parts. Jake explains how PEM hardware, such as nuts, studs, and standoffs, creates a mechanical bond that adds threads, spacing, or mounting points without weakening your part.
You’ll also learn about proper hardware types, materials, and installation directions, as well as how spacing, bends, and nearby features can affect manufacturability. The lesson walks through designing and placing holes in CAD, understanding max and min part sizes, and how SendCutSend installs hardware safely during production.
What you’ll learn:
- What insert (PEM) hardware is and when to use it
- The differences between studs, nuts, and standoffs
- How material choice affects hardware compatibility
- Proper pull directions and spacing for reliable installation
- How to design holes and avoid feature interference
- How SendCutSend installs hardware and handles finishing
- When to choose hardware inserts instead of tapping
Additional resources:
Hardware Guidelines
A Guide to PEM Hardware Inserts
Lesson 13: How to Improve Edge Quality with Tumbling and Deburring
In chapter 5 lesson 13, you’ll learn how to clean up your laser-cut parts and improve their surface feel using two main post-processing methods: tumbling and linear deburring. Jake explains how each process works, the differences in finish and edge quality, and when to use one method over the other depending on your material, part size, and desired result.
You’ll see how tumbling uses abrasive media to smooth and round edges for a soft, uniform texture, and how different media types affect the surface finish. Then, you’ll learn how linear deburring removes burrs and sharp edges using a sanding belt system, why it produces a flatter edge, and how part dimensions affect whether it can be processed successfully. Jake also covers key considerations like minimum part sizes, the difference between deburring and true finishing, and how each process prepares your parts for secondary operations like anodizing or powder coating.
What you’ll learn:
- The difference between tumbling and linear deburring
- How tumbling media smooths edges and surfaces
- How linear deburring removes burrs using belt sanding
- The pros and cons of each method for different materials
- Why part size and geometry affect deburring results
- The difference between deburring and true finishing
- How to select the right deburring process for your design
- How deburring prepares parts for coatings and final assembly
Additional resources:
Tumbling Guidelines
Tumbling vs Deburring
Deburring Guidelines
Lesson 14: How to Get Perfect Results with Additive Finishes
In chapter 5 lesson 14, you’ll learn how to design for additive finishes like powder coating, which protect your parts and enhance their appearance. Jake explains how these coatings add measurable thickness to both internal and external surfaces, affecting fit and tolerance.
You’ll also learn how to account for coating buildup on holes, tabs, and slots, when to include hanging holes for coating application, and how to handle hardware during finishing. By the end, you’ll understand how to prepare your parts so powder coating and other additive finishes look great, fit correctly, and last long in the field.
What you’ll learn:
- How additive finishes like powder coating protect and enhance parts
- How coating thickness affects part dimensions and fit
- Why to plan clearance for holes, tabs, and slots
- How to add hanging holes for coating application
- How to protect hardware and threads during finishing
- Why additive finishes are the final step before assembly or use
Additional resources:
Lesson 15: How to Plan Your Design for Anodized Finishes
In chapter 5 lesson 15, you’ll learn about anodizing and other non-coated finishes that enhance the durability, appearance, and functionality of your parts without adding a physical layer of material. Jake explains how anodizing works, an electrochemical process that creates a protective oxide layer on aluminum, improving corrosion resistance, surface hardness, and color options through dyes.
You’ll also learn how anodizing differs from additive coatings like powder coat, how it impacts electrical conductivity, and why certain materials use similar processes such as passivation for stainless steel or black oxide for carbon steel. Jake covers design considerations like when anodizing slightly changes part dimensions, and when to avoid welding or machining until after the process. The lesson wraps up with a walkthrough of how to select anodizing or powder coating finishes in SendCutSend’s ordering system and what to expect when your parts arrive.
What you’ll learn:
- What anodizing is and how it protects and strengthens aluminum
- The difference between anodizing and additive finishes like powder coating
- How anodizing affects corrosion resistance, hardness, and conductivity
- When to use anodizing, passivation, or black oxide based on material type
- How anodizing slightly alters dimensions and when it matters for design
- Why anodized parts should not be welded and how to plan post-processing
- How to select anodized or powder-coated finishes in SendCutSend checkout
Additional resources:
Lesson 16: The Capstone Project Part 1: Applying Every Skill You’ve Learned
In Capstone Part 1, you’ll turn everything from Chapters 1 through 5 into a real project by designing a desk organizer from scratch in CAD. Jake walks you through setting up a centered origin, creating sheet metal components as separate components, mirroring walls, building a wraparound back and base, adding an internal shelf, divider, and false bottom, and grounding parts to lock the assembly. You will also learn to control flange orientation and measurement references, match radii for safe edges, and inspect dimensions to keep the model manufacturable.
By the end, you will have a clean multi-component sheet metal assembly ready for detailing in Part 2 where you will resolve interferences, add hardware and holes, and prep for finishing.
What you’ll learn
- How to plan a sheet metal assembly with a centered origin and offset planes
- When to create components versus bodies and why grounding matters
- How to use flange options for side selection, bend position, and measurement reference
- How to mirror components and project geometry to drive new sketches
- How to add shelves, dividers, and internal flanges while maintaining clearances
- How to match fillet radii and verify dimensions with Inspect for DFM readiness
Lesson 17: Applying Every Skill You’ve Learned
In the Capstone part two, you pick up the build and finish the organizer by resolving interferences, adding clearances, and locking the assembly together with holes, tabs, and slots. You will also design the sliding drawer, parameterize the model so global edits propagate, and finalize services like hardware and powder coat in the SendCutSend cart.
What you’ll learn
- How to add clearance cuts and fillets to eliminate interference
- How to locate and pattern through holes that align with internal flanges
- How to design tabs and matching slots with proper fit allowance
- How to build a simple sheet metal drawer and add ergonomic cutouts
- How to use parameters so one edit updates the entire assembly
- How to apply DFM checks for hardware spacing, bend relief, and finish allowances
- How to configure hardware installation and powder coating in the SendCutSend cart
Thanks for completing SendCutSend Community College
That wraps up the first semester of SendCutSend Community College. More CAD tips and lessons will be coming so make sure to sign up to receive updates on new lessons at sendcutsend.com/education
