Proportional divider with a custom fixed ratio STL: Create a Custom-Size 3D Model

Transfer drawing distances at your chosen fixed ratio. Join the two identical double-ended arms at their offset bores using your own suitable bolt, washers and nut. Short arm length equals long arm length divided by the ratio. Open the short ends to a distance and the long ends show its enlargement; reverse the process to reduce. Arms are 4 mm thick, with blunt 2.4 mm end faces and no scale. Check against known distances before use and touch the ends lightly for comparison. It is not a piercing compass. Adjust the pivot to move smoothly while retaining its setting.

With the Proportional divider with a custom fixed ratio template, you can turn those measurements into a custom-size STL. Review controls such as long arm length, transfer ratio, pivot bore, check your model in the preview and choose the digital file. You buy the generated STL and print it on your own 3D printer, using your preferred filament and slicer settings.

Start with my measurements

Measurements for your proportional divider with a custom fixed ratio STL

The product page exposes the following useful geometry controls. Work from your measured parts and check the displayed units and the preview before entering final values.

Confirm the working geometry before buying the file

Compare the pictured shape with the actual task, not only the product name. Mark which faces touch other objects, which parts need to move and which pieces are supplied separately. The model controls change an existing design; they do not automatically add a feature that the template does not include. Check the complete motion or assembly space in the preview before choosing your final dimensions.

Configure the model, buy the STL and print locally

1. Open the proportional divider with a custom fixed ratio product page and compare the model preview with your application.
2. Enter the relevant measurements. Use the units displayed beside each input; convert inch measurements before using a millimetre field.
3. Review the complete geometry and keep a record of your parameter values. Check small openings, mating features and remaining wall thickness.
4. Choose the digital STL purchase option and review the current price and order details before payment.
5. After receiving the STL, open it in your slicer, confirm the imported dimensions and inspect the layer preview before printing.

Configure my proportional divider with a custom fixed ratio STL

Check a first print before making more

A CAD dimension and a printed dimension can differ. Print a fit sample or one prototype before making a batch, and check the features that contact other parts. Choose print orientation, supports and material for the actual geometry and application. There is no universal clearance or print profile that guarantees the fit on every machine.

Before you choose your STL

Why configure the model instead of scaling a download?

Uniform scaling changes all dimensions together. Here you can work with the available controls, including long arm length, transfer ratio, pivot bore, and check the result before purchase. Keep your input values for later revisions: the downloaded STL contains the final mesh, rather than the original parametric editing history.

What do I buy?

Select the digital STL option for the file you will print yourself. Review the current price and selected configuration before paying. Ordering a finished print is a separate option.

Make the next print fit your project

Have your measurements ready? Open the proportional divider with a custom fixed ratio template, adjust the model and inspect the preview. When the geometry matches what you need, choose your STL and take it to your own printer.