Free to use. Optional tips support testing and materials; they never unlock features.
Free hat block STL and 3MF generator
Create free hat blocks in STL and 3MF.
Create and download free 3D printable hat blocks for your measurements. Choose the finished hat size, head oval, crown height, and profile. Download STL files, or choose a supported printer and slicer setup for a configured 3MF project. The browser workshop and offline package are free, with no account, subscription, or paywall.
Generate a hat block in three steps
- Choose your measurements. Start with the intended finished hat size or a dependable circumference. Choose the head oval separately, then set the crown height and profile.
- Create the printable files. Generate the crown block and matching BS-1.0 stand as STL files, or use Printer Setup for a supported configured 3MF project. Files are generated locally on your device.
- Check before printing. Open the file in the intended slicer, keep the model at 100% scale, and confirm its dimensions and settings. Open a configured 3MF as a project. Follow the hat-block printing guide and use the recommended dimensional fit check for your printer and filament before a large crown print.
Full-size crown-block and matching stand STL files, plus configured 3MF projects for supported printer and slicer setups.
Round, standard oval, and long oval starting forms, with further shaping options in the Online Workshop.
Use a current browser, or download the offline-capable package for Windows, macOS, and Linux.
Choose STL or 3MF for your hat block
STL downloads contain model geometry. Select your actual printer and material in your slicer, then apply the settings supplied for your tool.
Configured 3MF downloads can also include printer, material, walls, infill and reinforcement settings for a supported setup. Choose the exact printer, nozzle, slicer and filament in Printer Setup, then open the 3MF as a project and inspect the sliced layers before printing.
Some workshops provide model-only 3MF files. The extension alone does not promise compatible print settings. The printer and slicer setup guide lists current export support, TESTING options, and the difference between a configured project and model-only files.
A hat block made for your project
This generator creates the crown form from your selections, so size, oval, height, and profile remain separate choices. Download the generated files and keep the package instructions together. The hat block sizes and head ovals guide explains how to choose a starting fit.
New to the terminology? Read what a hat block is and how crown blocks differ from brim tooling. The generated crown is an open form to shape at the bench; it is not a finished hat.
Need a brim block or another hatmaking tool?
The separate Open Road Style Brim Workshop provides released four-quadrant brim-block packages. Print the matching Fit Verification Coupon first at 100% scale before committing to a full brim print.
The Community Tool Crib offers free contributor tools with visible credit and original-source links. Crown blocks, brim blocks, and these tools serve different parts of the hatmaking process.