It seems like metal pen tips for digital pens are getting more popular. In this review, I'll share with you my findings on how metal pen tips perform for writing and drawing, and whether they can scratch the glass display.
Can metal scratch glass
For metal to scratch glass, the metal has to be harder than glass, and there has to be a point or cutting edge.
Here a list of metals and their Mohs scale of mineral resistance (hardness):
- Lead: 1.5
- Tin: 1.5
- Zinc: 2.5
- Gold: 2.5-3
- Silver: 2.5-3
- Aluminum: 2.5-3
- Copper: 3
- Brass: 3
- Bronze: 3
- Nickel: 4
- Platinum: 4-4.5
- Steel: 4-4.5
- Iron: 4.5
- Palladium: 4.75
- Rhodium: 6
- Titanium: 6
- Hardened steel: 7-8
- Tungsten: 7.5
- Tungsten carbide: 8.5-9
Glass has Moh hardness of 5.5 to 7 depending on how the glass is made.
You can see from the list above that most metals are softer than glass except for hardened steel and certain metal alloys. Sand can scratch glass though because both sand and glass are Silicon Dioxide.
Based on my testing, the metal pen tips did not scratch glass.
The first metal pen tip I saw is from the Huawei M Pencil 2 in 2021. That pen tip is coated with platinum (4 - 4.5 hardness). After that, metal pen tips became more common.
These are the pen nibs I purchased for testing from top left to bottom right:
- HB plastic nib (similar to original Apple Pencil tip)
- 2B plastic nib
- Needle point with translucent plastic body
- Needle point with white plastic body
- Round point with white plastic body
The metal used is copper (3 hardness) with nickel plating (4 hardness) and hence are in theory softer than glass.
This is the needle point tip. The thin needle point allows you to see the line beneath it more easily.
What I don't like about metal tips is the sound they make when they come in contact with glass. Metal point is slightly smoother than the original Apple Pencil tip.
Downside of this metal needle tip is there is wobble or jitter when drawing slow diagonal lines.
Pressure sensitivity works fine but here you can see noticeable wobble with the diagonal lines.
Another downside is tilt activates easily by tilting the pen slightly instead of much lower.
I pressed down hard on my iPad Pro to scratch the glass display but I could not create any scratches.
The round metal tip performs better than the needle tip.
It's possible to draw straight diagonal lines slowly with the round metal tip.
Pressure sensitivity works well.
Tilt sensitivity works well with the round metal tip too.
This is the 2B plastic tip is really nice. There is noticeably more resistance than the original Apple Pencil tip. You can find these online for less than US $1.50 each. That's a huge difference from the silicone PenTips2 I reviewed recently which is US $15 each. PenTips2 has slightly more resistance the 2B plastic nib shown above is more worth the money because it's way more affordable.
2B plastic tip can draw slow diagonal lines straight without wobble.
Pressure sensitivity works fine.
Tilt sensitivity works fine.
Are metal pen tips safe on glass displays? Yes.
Do I recommend metal pen tips? It depends. If you find that you wear down your plastic tips that often, perhaps it's better to get metal tips since metal is more resistant to wear and tear.
I don't like how the metal tips sound on glass. I prefer the 2B plastic nib which has resistance on glass and that can give you more control when drawing. For writing, you should just go with HB tip or the original Apple Pencil tips which are smoother on glass. Smoother pen tips are better for writing fast.
You can find these metal pen tips on AliExpress and they are all quite affordable.