8mm, 6mm or 3.5mm? A Practical Guide to Choosing Brass Type Size for Leather Hot Foil Stamping
There is a small mistake almost every leatherworker makes at some point.
You buy a beautiful brass type set. The letters look perfect in the product photo. The font feels right. The machine heats up nicely. Then you press it onto leather and somehow… it is not quite there.
Too small. Too loud. Too cramped. Too polite. Too much like an afterthought.
Most of the time, the problem is not the machine. It is not even the font. It is scale.
In leather hot foil stamping, size does a lot more than decide whether a word is readable. It decides the mood of the whole piece. A tiny 3.5mm name on the inside of a wallet feels discreet and personal. A 6mm name on a notebook cover feels balanced and useful. An 8mm monogram on a luggage tag feels confident, almost like part of the object’s identity.
That is why choosing between 3.5mm, 6mm and 8mm brass type is not just a technical decision. It is a design decision.
And if you are building a small leather goods brand, a gift personalisation service, or simply a better studio setup, it is one of those details worth getting right.
The simple rule: don’t choose the font size first
Start with the object.
That sounds obvious, but many people do it the other way round. They fall in love with a typeface, pick a size, then try to force it onto every wallet, tag, box and notebook.
A better way is to ask:
What is the piece?
Where will the text sit?
How far away will someone read it?
Is the text meant to whisper, speak, or make a statement?
That last question matters.
A maker’s mark inside a cardholder should probably whisper.
A customer name on a gift tag should speak clearly.
A large initial on a luggage tag can make a statement.
The brass type size should follow that job.
Good typography has always worked this way. Designers use size, spacing, weight and contrast to tell the eye what to notice first. Hot foil stamping is no different. The only difference is that once the text is pressed into leather, you cannot resize it with two fingers on a screen.
3.5mm: small, quiet, and better than people think
3.5mm type is easy to underestimate.
It does not look dramatic in photos, and it is not the size most people imagine when they think of personalised leather goods. But used in the right place, it can be incredibly elegant.
This is the size for small details: initials inside a wallet, a short date on a card sleeve, a quiet maker’s mark, a slim leather label, a pencil, a narrow strap, or the inside flap of a notebook cover.
It feels private. That is its charm.
A 3.5mm stamp is not trying to sell the product from across the room. It is the kind of detail someone notices after they pick the item up. For higher-end handmade work, that can be a beautiful thing.
But there is a catch. Small type has less room for error.
If the leather has a strong grain, if the pressure is uneven, or if the foil does not release cleanly, small letters can lose clarity faster than larger ones. Very thin typefaces can also become faint. So with 3.5mm brass type, you want to keep the wording short and the surface fairly controlled.
Good uses for 3.5mm:
Initials
Short dates
Small maker’s marks
Pencil stamping
Inside wallet details
Fine leather labels
Quiet personalisation
Less ideal for:
Long names
Large product fronts
Text meant to be read at a glance
Heavy-grain leather
Big branding moments
Think of 3.5mm as the size for restraint. It is not weak. It is just not trying to be the loudest thing in the room.
6mm: the safest everyday size for most leather projects
If you are choosing your first brass type set and you are not sure where to begin, 6mm is usually the most forgiving size.
It has enough presence to read clearly, but it does not take over the design. That makes it useful for wallets, passport covers, notebook covers, key tags, small leather labels, packaging, gift personalisation and short brand names.
In real studio use, 6mm often becomes the “reach for it without thinking too much” size. It works on many objects. It gives you enough visibility without demanding a large layout. It also tends to be easier to control than very small type, especially when you are still learning how your hot foil stamping machine behaves with different leather finishes.
6mm is especially good for:
Customer names
Short brand names
Notebook covers
Wallet and cardholder fronts
Passport holders
Small packaging details
Gift tags
Short phrases like MADE BY HAND or WITH LOVE
But 6mm is not one fixed visual feeling. The typeface changes everything.
A 6mm Arial can look clean, modern and practical.
A 6mm Plantin feels more traditional and bookish.
A 6mm Bookman Old Style has a warmer, heavier vintage feel.
A 6mm American Typewriter gives off more of a stationery, workshop, handmade mood.
A condensed typeface can help when the space is narrow, but it may not feel as open or relaxed.
This is where people often get confused. They think they are choosing a size, but really they are choosing a size plus a personality.
That is why a good brass type set should not only offer “letters”. It should offer typefaces that make sense for different brands and different objects.
8mm: when the words are part of the design, not just information
8mm brass type is not subtle. And that is exactly the point.
This is the size to consider when the stamped text should become a main feature of the piece. Think luggage tags, larger leather labels, notebook covers, gift packaging, brand tags, display pieces, initials, short names, and custom products where the lettering is meant to be seen straight away.
An 8mm letter gives the work a stronger visual anchor. It makes a name feel intentional. It makes a tag feel finished. It gives a plain leather surface a clear focal point.
Used well, 8mm type can make a product feel more designed.
Used badly, it can overwhelm the piece.
That is the honest part.
If the leather area is small, 8mm may look crowded. If the word is long, it may run out of space quickly. If the typeface is already heavy, the whole stamp may feel too dominant. So 8mm is best when you have room to breathe: a luggage tag, a cover, a label, a larger packaging panel, or a short bold word.
This is also where the CÍ 8mm brass hot foil stamping type set makes sense. It is not trying to replace smaller type. It fills a different role.
The set is built for makers who want a bolder stamping option for visible custom work. It includes 307 brass type pieces — uppercase letters, lowercase letters, numbers, symbols, punctuation and spacing pieces — together with a walnut storage box designed for larger type. The uppercase A is approximately 8mm high, while the lowercase letters, numbers and symbols are proportionally scaled.
That proportion matters. You do not want a set where the uppercase letters feel bold and everything else feels awkwardly patched in. A usable type set needs the whole alphabet system to feel coherent.
The walnut box is also not just there to make the product look nice. When you are working with hundreds of small brass pieces, storage becomes part of the workflow. If the letters are difficult to find, personalisation becomes slower, messier and more annoying than it needs to be.
Good uses for 8mm:
Luggage tags
Notebook covers
Large leather labels
Gift packaging
Short names
Initials
Brand words
Display pieces
Custom leather tags
Less ideal for:
Tiny wallets
Long sentences
Crowded layouts
Very narrow straps
Subtle interior marks
The easiest way to think about it:
3.5mm is a detail.
6mm is everyday text.
8mm is a design feature.
Bigger type also needs better spacing
There is one thing people do not talk about enough: the larger the letters, the more obvious the spacing becomes.
Small type can hide small spacing mistakes. Large type cannot.
With 8mm brass type, the space between letters, the margin around the word and the distance from the edge of the leather all become part of the design. A word stamped too close to the edge can look accidental. A name with uneven spacing can feel less premium, even if the foil itself is clean.
This is why spacing shims matter. They are not exciting, but they are useful. They help you control rhythm, especially when mixing uppercase letters, numbers and symbols.
For example, a luggage tag with a large name stamped across the centre may only need one line of text, but it needs breathing room around it. A notebook cover may look better with the name lower down rather than dead centre. A packaging label may need the brand name large, but the date or batch number smaller.
Good stamping is not just pressure and heat. It is composition.
Typeface choice: the same size can feel completely different
Two 8mm fonts can behave like two different products.
A clean sans serif typeface can look modern and direct. A serif typeface can look more literary, traditional or luxurious. A typewriter style can feel casual, archival or handmade. A condensed font can solve space problems, but it can also feel taller and sharper.
This is why it is useful to offer several typeface options rather than treating all brass type as interchangeable.
For example:
Arial is clean, neutral and easy to use.
Tw Cen MT Condensed works well when you need taller letters in a tighter space.
Plantin feels classic and bookish.
Bookman Old Style feels warm, full and slightly nostalgic.
American Typewriter has a stationery-like, handmade character.
Modern is more decorative and strong in personality.
Circle Fina feels lighter, cleaner and softer.
None of these is “best” in every case.
A minimalist passport cover may look better with Arial.
A leather journal might suit Plantin.
A handmade gift tag could work beautifully with American Typewriter.
A bold luggage tag might benefit from Bookman Old Style or another heavier face.
The real question is not “Which font is prettiest?”
It is “Which font feels like this object?”
Machine compatibility: look beyond the letter height
Here is the less glamorous but very important part.
When buying brass type, do not only check the letter height. Check the body size and holder compatibility.
The visible letter might be 8mm, but the brass block has its own physical dimensions. Your machine and holder need to grip that block properly. If the body size does not match the holder, the type may sit loosely, heat unevenly, or fail to align properly.
This is where a lot of frustration comes from. A maker buys a type set that looks right, then discovers it does not fit their holder, or it technically fits but is awkward to use.
CÍ’s 8mm brass type set is designed to work with Maxita Holder No. 1 and MOVEGO hot foil stamping machines. For other machines, the safest approach is to check the type specifications shown in the product images before ordering. If there is any doubt, ask first.
It sounds simple, but it can save a lot of trouble.
A good hot foil stamping setup is a system: machine, holder, brass type, foil, leather, pressure, temperature and layout. If one part is off, the final result usually shows it.
Maxita, MOVEGO and the idea of a complete stamping setup
For some makers, a hot foil stamping machine is just a way to press a logo.
For small brands, it can become much more than that.
Once you have movable brass type, you can stamp names, initials, dates, batch numbers, short phrases, product labels and packaging details. Add a custom logo stamp, and you can build a more complete visual language for your brand.
That is why Maxita and MOVEGO are interesting tools for leather studios. The machine is only the centre of the setup. Around it, you need the right holder, type set, foil, logo stamps, storage and support.
This is also where CÍ’s role is more useful than just selling one product. CÍ curates and develops tools for leathercraft and handmade studios, including hot foil stamping machines, brass type, custom logo stamps, foil paper, storage boxes and tailored tools. For a maker trying to build a reliable bench setup, that matters.
Because sometimes the real question is not “Which letter set should I buy?”
It is:
Will this fit my machine?
Can I get a custom font later?
Can I order a logo stamp that works with the same setup?
Can I get help if the result is not clean?
Can I build this into a repeatable workflow for customer orders?
That is the kind of support a small studio actually needs.
A practical size guide
If you want a quick way to choose, start here.
Choose 3.5mm if the text is small, private or secondary. It is best for fine details, initials, dates, inner marks and narrow surfaces.
Choose 6mm if you want a flexible everyday size. It works for most names, wallets, notebook covers, passport holders, key tags and gift personalisation.
Choose 8mm if the text is meant to be seen. It is best for luggage tags, large labels, covers, packaging, bold initials and brand-facing details.
Still unsure? Look at the object, not the alphabet.
For a wallet: 3.5mm or 6mm.
For a passport holder: 6mm.
For a notebook cover: 6mm or 8mm.
For a luggage tag: 8mm.
For a narrow strap: 3.5mm or 6mm.
For packaging: 6mm for detail, 8mm for the front-facing name or logo.
For a maker’s mark: 3.5mm if quiet, 6mm if visible.
For a short brand word: 6mm or 8mm, depending on the surface.
There is no perfect universal size. There is only the right size for the job.
What makes a brass type set worth keeping?
A good type set is not just a pile of letters.
It should have enough commonly used letters. It should include numbers, symbols, punctuation and spacing pieces. It should fit the holder properly. It should be easy to organise. It should come in typefaces that suit real products, not just look nice in a catalogue.
And ideally, it should be part of a setup you can grow over time.
That is one reason the CÍ 8mm set was developed with 307 pieces and a walnut storage box. It is meant for makers who do repeated personalisation work and need the letters to feel practical, not just decorative. The option to discuss custom fonts and sizes also matters, especially for studios that care about brand consistency.
If your work is a one-off hobby project, you may not need that level of flexibility.
But if you run a small leather goods brand, take custom orders, make gifts, sell personalised notebooks, or create packaging for your own products, your type set becomes part of your brand system.
And that is worth choosing carefully.
Final thought: type size is really about confidence
Small letters can feel refined. Medium letters can feel balanced. Large letters can feel confident.
The trick is not to make every stamp louder. The trick is to know when the work needs quiet detail, when it needs clear information, and when it deserves a bold focal point.
That is the difference between lettering that simply sits on leather and lettering that belongs there.
For most makers, the smartest setup is not one perfect size. It is a small system:
3.5mm for subtle details.
6mm for everyday personalisation.
8mm for strong visual moments.
Once those roles are clear, the choice becomes much easier.
And if you are building a hot foil stamping setup around Maxita, MOVEGO or a similar machine, it is worth looking beyond the machine itself. The holder, brass type, foil, storage and after-sales support all affect how enjoyable — and how repeatable — your stamping work becomes.
That is where CÍ tries to be useful: not just as a place to buy one tool, but as a craft tool shop that understands the full bench setup. From hot foil stamping machines and brass type sets to custom logo stamps, walnut storage boxes, foil paper and tailored tools, the goal is simple: help makers create cleaner, more confident work without having to figure out every tiny compatibility problem alone.
References
CÍ Official. n.d. Complete Hot Foil Stamping Solution. CÍ Official.
CÍ Official. n.d. CÍ Deluxe Brass Type Kit with Premium Walnut Box. CÍ Official.
CÍ Official. n.d. MOVEGO vs Maxita Hot Foil Stamping Machine: Which One Should You Choose for Leather Branding, Custom Stamps and Small-Batch Personalisation? CÍ Official.
Nielsen Norman Group. 2017. Typography for Glanceable Reading: Bigger Is Better. Nielsen Norman Group.
Nielsen Norman Group. 2022. The Dos and Don’ts of Pairing Typefaces. Nielsen Norman Group.
Nielsen Norman Group. 2024. Typography Terms: Glossary. Nielsen Norman Group.
Leatherworker.net. 2025. How to Choose the Right Font and Size for Brass Letters in Foil Stamping. Leatherworker.net Forum.
Reddit. 2020. Help with Metal Letterpress Type. r/bookbinding.
