PartWork.ai Blog
Guides for designing, converting and making real parts
Practical guides on AI-powered CAD, 3D printing, file formats, and designing real parts — without a steep learning curve.
What Is an IGES File? .IGS and .IGES Files Explained
IGES is the 1980 neutral CAD format for exact curves and surfaces. What is inside one, why it is often not a solid, how .igs and .iges differ, and how to open one or turn it into STEP.
File FormatsHow to Add a 3D Model to Your Website: Even From a Drawing
Which 3D file to use, how to embed a free 3D viewer with one line of HTML or a WordPress plugin, and how to show a part in 3D when all you have is its drawing.
ManufacturingWelding Symbols: How to Read Weld Symbols on a Drawing
A welding symbols chart and how to read one: the reference line, arrow side and other side, fillet and groove weld symbols, sizes, and all-around and field welds.
ManufacturingWhat Is an Assembly Drawing? Parts List, Balloons and How to Read One
What an assembly drawing shows, how it differs from a detail drawing, how to read the parts list and balloons, weldment drawings, and how to turn one into a 3D model.
ManufacturingFirst Angle vs Third Angle Projection: View Layout and Symbol Explained
Where each view goes in first and third angle projection, how to read the projection symbol, which countries use which, and how to avoid making a mirrored part.
ManufacturingHow to Read Engineering Drawings: A Step-by-Step Guide for Mechanical Parts
Read a drawing in order: the title block, views and first or third angle projection, line types, dimensions and tolerances, notes and revisions, and the mistakes that scrap parts.
ManufacturingSurface Finish Chart: Ra, RMS and N Grades, With Symbols Explained
Ra in micrometres and microinches, RMS, Rz and ISO N grades in one chart, the finish each machining process reaches, and how to read the roughness symbol, lay marks and old triangle marks on a drawing.
ManufacturingEngineering Drawing Symbols: What Each One Means, With Examples
Diameter, radius, counterbore, countersink, depth, GD&T, surface finish, threads, line types and abbreviations: every common symbol on a print, with a real callout for each.
ManufacturingAI Tools That Turn Engineering Drawings into CAD (2026)
Backflip, Theia, Aibuild, Drawing Agent and PartWork.ai compared: inputs, outputs, prices, and who does quality control against your drawing.
ManufacturingOnly Have a PDF Drawing? How to Get an Instant Machining Quote
Instant-quote sites price parts from a 3D STEP file, not a PDF print. Four ways to get one from your drawing, what to upload with it, and five checks before you order.
File FormatsSTEP AP203 vs AP214 vs AP242: Which STEP Format Should You Export?
All three hold the same solid geometry. AP214 adds colours and layers, AP242 adds machine-readable tolerances. Which to send a machine shop, and how to check a file.
ManufacturingMylar Engineering Drawings to CAD: Turn Old Prints into 3D Models
How to scan old mylar, blueprint and paper drawings, why a scan is not CAD, the traps in legacy prints, and three ways to get a 3D STEP model of the part.
ManufacturingHow to Convert a PDF to CAD: 2D DWG vs a Real 3D Model
Three ways to turn a PDF drawing into CAD: redraw it by hand, trace it to a 2D DWG, or get a 3D STEP model with AI. When a DWG is all you need, and when you need the part in 3D.
Manufacturing3D Scanning for Reverse Engineering: When the Drawing Is Enough
Before you ship a part out for a 3D scan, check the filing cabinet. If you have its 2D drawing, a STEP file can come from the drawing in minutes. When scanning still wins, and why.
Manufacturing2D Drawing to 3D Model: How to Convert 2D Drawings to 3D STEP Files
Drawing to STEP: turn legacy PDF, scanned or photographed drawings into 3D STEP files you can upload for instant quotes from Protolabs, Xometry and others, without redrawing them by hand.
File FormatsDrawing to 3D Model with AI: Why You Need a STEP File, Not a Mesh
AI 3D generators turn an image into a mesh. A machine shop needs a STEP solid at the drawing’s exact dimensions. Mesh vs B-rep in plain English, and when each is the right tool.
ReferenceM12 Screw Hole Size: Clearance and Tap Drill Diameters
The exact hole size for an M12 screw or bolt — clearance holes (13.0–14.5 mm) so it passes through, and the 10.2 mm tap drill if you’re threading — plus the extra clearance 3D-printed M12 holes need.
ReferenceM10 Screw Hole Size: Clearance and Tap Drill Diameters
The exact hole size for an M10 screw or bolt — clearance holes (10.5–12.0 mm) so it passes through, and the 8.5 mm tap drill if you’re threading — plus the extra clearance 3D-printed M10 holes need.
ReferenceM8 Screw Hole Size: Clearance and Tap Drill Diameters
The exact hole size for an M8 screw — clearance holes (8.4–10.0 mm) so it passes through, and the 6.8 mm tap drill if you’re threading — plus the extra clearance 3D-printed M8 holes need.
ReferenceM6 Screw Hole Size: Clearance and Tap Drill Diameters
The exact hole size for an M6 screw — clearance holes (6.4–7.0 mm) so it passes through, and the 5.0 mm tap drill if you’re threading — plus the extra clearance 3D-printed M6 holes need.
ReferenceM4 Screw Hole Size: Clearance and Tap Drill Diameters
The exact hole size for an M4 screw — clearance holes (4.3–4.8 mm) so it passes through, and the 3.3 mm tap drill if you’re threading — plus the extra clearance 3D-printed M4 holes need.
ReferenceM5 Screw Hole Size: Clearance and Tap Drill Diameters
The exact hole size for an M5 screw — clearance holes (5.3–5.8 mm) so it passes through, and the 4.2 mm tap drill if you’re threading — plus the extra clearance 3D-printed M5 holes need.
ReferenceM3 Screw Hole Size: Clearance and Tap Drill Diameters
The exact hole size for an M3 screw — clearance holes (3.2–3.6 mm) so it passes through, and the 2.5 mm tap drill if you’re threading — plus the extra clearance 3D-printed M3 holes need.
File FormatsCan You Convert STL to STEP? Mesh to Solid, Explained
How to convert an STL to a STEP file, and the honest catch: mesh → solid is the hard direction. What a converter can really do, when it works, and the faster way to a clean STEP.
File FormatsIGES to STEP Converter: Why and How to Convert Online
How to convert an IGES file to STEP and why you’d want to: STEP is the modern solid format CAD and machine shops prefer. What changes, when it’s clean, and how to convert in your browser.
File FormatsHow to Open a STEP File (.stp): Viewer, CAD Software, or AutoCAD
Double-clicked a .step file and nothing happened? Four ways to open a STEP or STP file: a free browser viewer, FreeCAD or any CAD program, AutoCAD IMPORT, or convert it to STL.
File FormatsConvert STEP to STL Online (Free to View) — How and When
How to convert a STEP file to STL for 3D printing: what the conversion changes, choosing resolution, why it’s one-way, and how to convert in your browser — view free, sign up to download.
ReferenceHow to Design a Washer or Spacer (Sizes for M3, M4, M5, M6)
A washer or spacer is the simplest functional part there is. How to pick the inner diameter, outer diameter, and thickness — with a metric size chart for M3–M6 and 3D-printing tips.
File FormatsThe Best Mobile 3D Part Viewers (View STEP/STL on Your Phone)
Need to open a STEP or STL file on your phone? The best ways to view a 3D part on iPhone and Android, what each format needs, and how to view any CAD file free in your browser.
File Formats3D CAD File Conversion Tools (STEP, STL, IGES, 3MF) — Convert Online Free
Convert STEP to STL, IGES to STEP, or STEP to 3MF online. How CAD conversion works, which formats convert cleanly, and how to convert a part free in your browser.
ReferenceMetric Clearance Hole Size Chart (M2–M12 Close, Normal, Loose)
Close, normal, and loose clearance hole diameters for metric bolts M2 through M12 — so a bolt passes straight through without binding — plus the extra clearance 3D-printed holes need.
ReferenceCountersink vs Counterbore: Which to Use and the Size Chart
A countersink seats a flat-head screw flush with a cone; a counterbore hides a socket-head cap screw in a flat pocket. When to use each, plus a metric size chart for both.
ManufacturingTolerance Stackup Basics: Why Parts That Should Fit Don’t
Small allowed errors on each dimension add up across a part or assembly. The worst-case method in plain English, where stackup bites, and five ways to design around it.
ManufacturingDraft Angle Explained: What It Is and When You Need It
What is a draft angle? The taper on vertical walls so a part releases cleanly from a mold or print bed — when you need one, how much to add, and how to apply it.
3D PrintingRib vs Gusset: The Difference, and How to Size Each
A rib stops a flat span bending; a gusset stops a corner opening. How thick, how tall and where to put each, and how to avoid the sink-mark trap.
File FormatsWhat Is a 3MF File? (.3mf) Explained for 3D Printing
A 3MF is the modern 3D printing container: geometry, units, color, and print settings in one file. How it improves on STL and when to use it.
3D PrintingWall Thickness for 3D Printing: Minimum Sizes That Print Cleanly
How thick should a wall be for 3D printing? Practical minimum wall thickness for FDM and resin, why thin walls warp and gap, and how to set a reliable wall you can tune.
File FormatsWhat Is a DXF File? (.dxf) Explained for Cutting and CAD
A DXF is a 2D drawing a laser cutter or CNC router can follow. What it stores, how it differs from STEP and STL, what makes one cut cleanly, and how to export one.
3D PrintingHeat-Set Inserts for 3D Printing: Strong, Reusable Threads in Plastic
Tapped plastic threads strip. Heat-set brass inserts give reusable metal threads — if the part is designed for them. The hole to model, boss wall and depth, and when to use them.
Getting StartedSingle Parts vs Assemblies in Text to CAD: What to Ask For
Text to CAD designs one solid part per request. The difference between a part and an assembly, how to break an assembly into parts you can make today, and where an assembly drawing goes instead.
ProjectsHow to Design a Mounting Plate (Custom Bolt Pattern, Step by Step)
Need a flat plate to mount a motor, sensor, or device? How to capture the bolt pattern, pick thickness, add clearance holes, and export a mounting plate ready to print or machine.
File FormatsSTL vs 3MF: Which File Should You Export for 3D Printing?
STL and 3MF both feed a 3D printer, but 3MF is the newer, richer format. The plain-English difference, when to pick each, and how to export both from PartWork.ai.
3D PrintingHow to Design a Bracket for 3D Printing (Step by Step)
A practical walkthrough for designing a strong, printable mounting bracket — wall thickness, hole sizing, fillets, and exporting an STL — using AI CAD instead of learning a heavy desktop tool.
File FormatsSTL vs STEP: Which File Format Should You Export?
STL for 3D printing, STEP for CNC and editing. Here is the plain-English difference, when to use each, and how to export both from PartWork.ai.
Getting StartedFree Online CAD With No Download: How to Design a Part in Your Browser
Free online CAD runs in a browser tab with nothing to install. Which kind fits your job, what is free, and how to export STEP or STL.
AI CADUsing an AI Parametric Part Generator to Design Custom Parts Fast
Describe the part you need in plain English and get editable 3D geometry. How AI parametric generation works, where it shines, and how to get good results.
3D PrintingTolerances for 3D Printed Parts: How to Get Parts That Actually Fit
Why your holes print too tight and your lids do not snap on — and the simple clearance values that make 3D printed parts fit the first time.
ReferenceBolt Hole Size Chart for 3D Printing (M3, M4, M5 Clearance & Tap)
A plain bolt hole size chart for 3D printing: clearance holes for M3, M4, and M5, when to tap vs. use a nut, and how to add them in seconds.
ProjectsHow to Design an Enclosure for Electronics (Project Box, Step by Step)
Design a custom project box for your PCB or electronics: internal clearances, mounting bosses, lid fit, and cutouts for ports — using AI CAD in your browser.
CNCCAD for CNC Machining: A Beginner’s Guide to Designing Machinable Parts
New to CNC? Here is how to design parts a machine shop can actually cut — STEP files, sharp internal corners, tool access, and tolerances — without years of CAD.
DeveloperPartWork.ai Developer API Guide: Generate CAD Parts Programmatically
How to create an API key, authenticate with X-API-Key, call the generate endpoint, poll for results, and download a STEP or STL file — a complete working walkthrough.
Laser CuttingDXF for Laser Cutting: How to Design and Export a Cut-Ready File
What a DXF file is, why laser cutters use them, and how to design a flat part with closed profiles, correct units, and kerf compensation — and export it for a cutter.
Getting StartedWhat Is Parametric CAD? Plain-English Guide for Beginners
Parametric CAD stores dimensions as editable constraints — change one number and the whole part updates. How it works, why it beats direct modeling for mechanical parts, and how AI makes it accessible.
How-ToFillet vs Chamfer: How to Add Them and When to Use Each
A fillet rounds an edge; a chamfer bevels it. Here is the plain-English difference, a simple rule for which to use, what size to pick, and how to add either in seconds with AI CAD.
How-ToHow to Design a Gear in CAD (Spur Gear Basics)
A spur gear is defined by just a few numbers. What module, teeth, and pitch diameter mean, how to make two gears mesh, 3D printing tips, and how to generate a gear with AI.
How-ToHow to Convert a Sketch to a 3D Model (Drawing to CAD)
Turn a 2D sketch into an editable 3D part. The sketch-to-extrude workflow, what details to capture, and how to convert a drawing fast with AI CAD in your browser.
File FormatsSTEP vs IGES: Which CAD File Format Should You Use?
STEP carries a full solid; IGES is the older surface format. How they compare with STL, Parasolid and native CAD files, which ones new CAD programs read, and what to send a machine shop.
ProjectsHow to Design a Custom Phone or Tablet Mount
Design a phone or tablet mount that fits your exact device: how to measure it, add the right clearance, build the clip and arm, and 3D print it — using AI CAD in your browser.
CNCThe Best File Format to Send a Machine Shop
Send a CNC shop the wrong file and you delay your quote. Here is the best file format for a machine shop — STEP — why, what to include with it, and how to export one fast.
How-ToHow to Measure a Part for Replacement (Reverse-Engineer a Broken Part)
A broken part with no drawing? Here is how to measure it, which dimensions actually matter, the tools to use, and how to turn your measurements into a printable or machinable replacement.
How-ToHow to Add Threads to a Part (Tapped vs Clearance Holes)
Should your part have a threaded hole or a plain clearance hole? Tapped vs clearance holes, how to read a callout like M3 or 1/4-20, and how to add the right hole in seconds.
How-ToPress-Fit and Snap-Fit Design: Join Parts Without Fasteners
Design press-fit and snap-fit joints that hold without screws or glue: the interference and clearance values that work, how to size a snap hook, and how to add them with AI CAD.
File FormatsWhat Is a STEP File? STEP vs STP, and What’s Inside
A STEP file is a 3D CAD model in the ISO 10303 standard: what is inside one, what it leaves out, .step vs .stp, STEP vs STL, which version to export, and how to make one.
Make your own part
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