Inktend / Pen library / Ink

Karas Kustoms

Ink

✓ Verified specs
KI
Shop Karas Kustoms Ink ↗

A fully machined metal pen assembled from interchangeable aluminum, brass, or copper parts — noticeably heavier and more industrial than most fountain pens in its price range.

A solid mid-range option once someone has decided fountain pens are a habit worth investing a bit more into.

Specs

Filling systemCartridge / converter
Ink capacityStandard international cartridge or converter
Nib optionsEF, F, M, B (steel, Bock)
MaterialAluminum, brass, or copper bar stock
Typical price~$80–110
How long has your Ink been inked?
Inktend counts the days and reminds you when it's time to clean.
Track it →

About Karas Kustoms

A Mesa, Arizona machine shop that built its name on fully-machined aluminum, brass, and copper pens — an early fixture of the everyday-carry pen revival. This model — Ink — dates to Karas Kustoms' first fountain pen, built with the same machined bar-stock approach as the brand's other writing instruments.

United States Founded c. 2011
See all Karas Kustoms products →

How to fill the Karas Kustoms Ink

Fill it two ways: snap in a pre-filled international cartridge for convenience, or use a converter — a small plunger or twist mechanism that installs the same way a cartridge does — to draw ink from any bottle. The converter route opens up the entire world of bottled ink, which is where most of the hobby's color variety lives.

Choosing a nib size

Nib size determines line width, not writing pressure — fountain pens are meant to glide, never press. Extra-fine (EF) suits small, dense handwriting and thin paper; fine (F) is the most broadly recommended default; medium (M) shows more ink character and shading; broad (B) and stub grinds favor bold, expressive strokes and calligraphy-adjacent writing.

Keeping it clean

A quick flush with cool water every time you switch ink colors — and a full clean every 4–6 weeks of regular use — is enough to keep the nib and feed performing well. Inktend's cleaning reminder is tuned to a 21-day baseline and adjusts naturally to how often you actually refill.

Pairing inks with the Ink

Because refills are quick with a cartridge or converter, this is a good pen for rotating through several colors rather than committing to one; sample vials work especially well here.

Kiri-same
Pilot Iroshizuku
4001 Brilliant Black
Pelikan
Aqua Lagoon
Diamine

Browse the full ink library →

Frequently asked questions

How do I fill the Karas Kustoms Ink?
Snap in a pre-filled cartridge, or use a converter to draw ink from any bottle. The converter route is the cheaper long-term option.
What nib size should I get for the Ink?
Fine (F) is the safest default for a first pen. Go finer for small, dense handwriting; go broader if you want more ink character and shading.
How often does the Ink need cleaning?
Flush it each time you switch inks, and give it a full clean every 4 to 6 weeks of regular use.
Is the Karas Kustoms Ink good for beginners?
It can work as a first pen if you're comfortable spending a bit more to start.

More from Karas Kustoms

KF
Fountain K
Karas Kustoms

Specs on this page have been individually verified against manufacturer and retailer listings.