christian.loelkes

With a simple shortcode you can enable and embed a WebGL viewer to show 3d stl files.
In the current version:
<ul>
<li>STL files have to be uploaded to /wp-content/uploads</li>
<li>The viewer can’t be used more than one time per page. This might be a feature because the viewer needs a lot of resources.</li>
</ul>
A complete description of the plugin can be found on <a href="https://www.db4cl.com/projects/stlviewer-1-0-for-wordpress/" rel="nofollow ugc">my blog</a>.

STL Viewer

With a simple shortcode you can enable and embed a WebGL viewer to show 3d stl files.

fuzzoid

If you have a 3D printer and wish to charge for model printing this plugin is for you.
How it works:
Site administrator configures printers, materials and pricing in the admin. Customers upload their models, choose printer and material, see the estimated price, input their email address and comments and press the “Request a Quote” button. 
The admin receives the request notification by email and sends the quotes through the Price Request Manager or discards the quote requests.
Features:
<ul>
<li>Supported file types: STL (bin, ascii), OBJ (+.mtl), ZIP.</li>
<li>Configurable printers, filaments and coatings.</li>
<li>Build tray shape (rectangle, circle).</li>
<li>Material/coating shininess (plastic, wood, metal).</li>
<li>Transparent and glowing materials.</li>
<li>Customizable pricing: can be configured to charge per model weight, filament volume or bounding box volume.</li>
<li>Large file upload support (upload chunking).</li>
<li>Model scaling.</li>
<li>Drag and drop.</li>
<li>Filament price calculator.</li>
<li>Email notification.</li>
<li>Email templates.</li>
<li>Price request manager.</li>
<li>Translation ready.</li>
<li>Responsive layout.</li>
</ul>
Demo: http://www.wp3dprinting.com/3d-print-lite-demo/
Premium version of the plugin has all features of the lite version plus:
<ul>
<li>WooCommerce integration.</li>
<li>Laser cutting support.</li>
<li>Bulk Upload Mode.</li>
<li>Form Builder (NinjaForms integration)</li>
<li>File Manager</li>
<li>Extra file type supported: STP, IGS, DXF</li>
<li>Image printing: JPG, PNG, GIF, BMP files get converted to STL.</li>
<li>Can arrange multiple STL models from a ZIP file.</li>
<li>Model scaling (can scale axis independently).</li>
<li>Extra layout options.</li>
<li>Model repair & optimization (auto rotation for optimized 3D printing process)</li>
<li>Manual model rotation.</li>
<li>Infill calculation.</li>
<li>Per hour pricing.</li>
<li>Support material calculation.</li>
<li>Ability to add predefined models to products.</li>
<li>Email template manager.</li>
<li>Discount system.</li>
<li>Fullscreen mode.</li>
<li>Custom attributes with configurable price.</li>
<li>Ability to assign different printers and materials to different products.</li>
<li>Free support.</li>
<li>New cool features to come.</li>
</ul>

3DPrint Lite

A plugin for selling 3D printing services.

STL Viewer vs 3DPrint Lite