Looking after the pen
Wipe the outside with an alcohol wipe, keep liquid out of the barrel, and replace the plastic cartridge holder when it clouds or cracks. Never submerge a pen, never autoclave one, and never put anything wet inside the mechanism.
The whole routine
- Wipe the body and the dial with an alcohol wipe when it needs it
- Keep the cartridge holder clean and dry, inside and out
- Store it dialled to zero, not left wound out
- Replace the cartridge holder if it clouds, cracks or crazes
- Keep it out of direct sun and out of a hot car
That is the lot. There is no servicing, no lubrication and no part that wears out on a schedule.
Why liquid inside is the one real danger
The dial mechanism is a fine thread in a dry housing. Get liquid into it and residue dries in the thread, which is when clicks start to feel gritty or the dial jumps. There is no practical way to flush it out afterwards.
So: no rinsing under a tap, no soaking, no spraying alcohol into the open end. Wipe the outside only.
The cartridge holder
The clear plastic sleeve that holds the cartridge is the only part that wears. It clouds with repeated alcohol contact and can craze if dropped. It takes ten seconds to swap, and both reusable pens come with a spare in the box.
Store the pen with the dial at zero. Leaving it wound out keeps the internal spring compressed for no reason and makes the first click of the next dose feel odd.
Questions
- Can I sterilise my pen?
- No, and you do not need to. Nothing sterile touches it: the needle is sterile and single-use, and the cartridge is sealed. The pen body is the handle.
- Should I remove the cartridge between injections?
- No. Leave it in with the needle removed. Taking it in and out adds wear to the holder for no benefit.
- How long should a pen last?
- Years of normal use. The wearing parts are the holder and the cartridge, both of which are consumables.
Duihao V3 Reusable Pen
Reusable metal pen with a closed cap and pocket clip.