Choosing Your Split Flap Font at Oat Foundry

Oat Foundry Split Flap displays use a signature font set by default, but we allow our customers to provide their preferred typeface. As part of our full branding capabilities, this enables brands to fully customize an installation for their unique space.

One design constraint is our module size: every Split Flap module contains 50 flaps, so adding new characters, colors, or icons means removing something else from the character set.

Prioritizing Legibility

Legibility has always been key for informational displays. The MTA famously uses Helvetica on its signage, and throughout history, transit systems such as the London Underground have used custom fonts since 1913.

Our standard font is also custom-designed for our Split Flap displays. The typeface was inspired by the original Solari boards and other transit signage; it’s designed to be legible from distances of up to 100 feet. That’s why font choice is so important: the right font can be read across busy spaces and far sightlines, whereas a less legible font won’t be as effective in a commercial setting. 

Our Classic Black (white text on a black background) and Modern White (black text on a white background) are both high-contrast options, which is extremely important for legibility. 

Here’s an overview of what we advise when choosing the right typeface for your Split Flap display:

Avoid Fonts That Are Too Bold

• Extra-bold fonts reduce the usable size of the character.
• Similar letterforms can become difficult to distinguish.

Avoid Fonts That Are Too Thin

• Thin or light fonts may not provide enough contrast against the flap.
• Prioritize clear strokes that remain visible at a distance.

Be Careful With Serif Fonts

• Serif fonts are generally less legible from a distance.
• There may be situations where branding may need to be balanced against readability (this is where a sales demo can really help).

Script Fonts Aren’t Recommended

• Script typography introduces readability challenges on individual mechanical flaps.
• Decorative letterforms become difficult to interpret quickly.

Lowercase Letters Can Create Alignment Issues

• Lowercase fonts are discouraged because they reduce legibility at a distance.
• Baselines can also appear less consistent across the display.

Adding Custom Characters and Languages

Many clients want to add new characters, icons, or color flaps. However, because each module houses 50 flaps per carousel, adding something means swapping out a character. Here’s how we advise adding custom characters or different (non-English) languages. 

Combine Similar Characters When Possible

• In Oat Foundry’s standard font:
  • “O” and “0” share a flap.
  • “I” and “1” share a flap.
• Custom fonts may require separating those characters, which means removing other punctuation or symbols.

Substitute Symbols Based on Location or Use

• Character sets can be localized.
• Example: a client replaced the U.S. dollar sign with the GBP symbol

Design for Accented Characters

• Accented characters require additional space within the flap.
• Letters may need to be slightly smaller to accommodate accents.
• Adding accented characters may also mean removing some or all punctuation from the 50-flap set.

Going Beyond The Alphabet

Some clients don’t want to use a full alphabet. In these cases, the character set can be fully customized to the display’s purpose. For example, some applications may only require numbers rather than letters and symbols. We had a client who created an all-numeric custom font set. Substitutions are common and easy to make in coordination with our talented sales team. 

A Simple Checklist for Planning Your Split Flap Font

• Choose a primary, legible-from-a-distance typeface.
• Avoid overly thin, bold, decorative, or complicated characters.
• Decide whether lowercase letters are necessary.
• Determine which punctuation and symbols you actually need.
• Decide whether you need special characters or accents.
• Choose any custom color flaps.
• Plan for geographic substitutions such as $, £, or other symbols.
• Make sure the final character set fits within the 50-flap limit.

Building Font Around the Experience

Custom Split Flap fonts offer a lot of creative freedom, but the best designs balance branding with readability and mechanical constraints. For teams looking for a highly customized and branded display, our sales team can help translate a chosen typeface and desired character set into production-ready font sets.