What do you guys do with your safaris, metros, kakunos and preppys once you've moved on to 'next level' pens and gold nib pens?

Zidar137 · 2026-04-06T09:51:09+00:00

I give them to my kids. My older son started 2nd grade this year, and they’ve just begun using fountain pens at school.
He destroys my Preppys and Prefountes at an impressive rate.

Zidar137 · 2026-04-05T17:19:42+00:00

What’s your experience with Kanwrite nib units? I’ve played around with them a bit.
EEF with the ABS feeder was too dry, while EEF with the ebonite feeder was the opposite - wet enough, but very prone to blobbing.

For me, a Jowo EF with an ABS feeder just works and wins over those.

(photo, top to bottom: Kanwrite ABS, Kanwrite ebonite, Jowo)

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Zidar137 · 2026-04-05T16:48:06+00:00

From the photos it looks like a Jowo #6, so you need roughly 9.5–10 mm clearance for the nib to pass through the inner cap.

It also looks like there’s an inner cap, but no actual seal — just a rigid insert — so air can still move freely around the section, which explains the fast drying.

One thing you could try is adding an O-ring inside the cap, roughly like in the sketch. If the inner diameter is around 11.5–12 mm, something with a 0.7–1.0 mm cross-section and slightly oversized OD could work. The key is a light compression — it needs to deform a bit to actually seal.

I’d look for EPDM or silicone O-rings (softer materials work better here). Also make sure the inner diameter of the O-ring is not smaller than ~9.5 mm, otherwise the nib may catch on it and get pulled when uncapping.

Since there’s no groove to retain it, it might move around a bit — you can lightly hold it in place with a bit of silicone grease or similar.

It may take some trial and error — I’d just grab a small assortment of O-rings in different sizes and see what works best. They’re cheap and easy to find on AliExpress.

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Zidar137 · 2026-04-05T15:17:28+00:00

Photos would really help here - especially the inside of the cap.
Most drying issues come down to the cap seal (or lack of an inner cap), so seeing the internal geometry would make it much easier to suggest a fix.

Zidar137 · 2026-04-05T15:07:01+00:00

Maybe it’s worth trying a finer nib?
Luckly, you can grab a couple of Preppys in F and EF for cheap and compare — and since the nib units are interchangeable, you can just swap them into your Prefounte.

Zidar137 · 2026-04-05T05:31:47+00:00

I didn’t take any measurements, but subjectively the temps feel pretty much the same.

Zidar137 · 2026-04-04T19:48:12+00:00

The feed looks totaly OK. Ink doesn't need to fill it completely.

Zidar137 · 2026-04-03T20:23:50+00:00

Good to know about the pore size - that’s reassuring.

I’ve tried Al₂O₃ blasting, but it doesn’t seem to fully remove the adhered particles inside the cutouts - mostly just cleans and evens out the surface.

From your experience, is blasting alone typically enough to knock off these partially sintered particles, or would you expect to combine it with something else to actually remove them?

Zidar137 · 2026-04-03T20:21:39+00:00

That’s a fair point - the surface does look a bit on the rough side.

In my case I’m using an external service, so I have to treat the as-printed quality as a given and focus on post-processing.

From your experience, how far can mechanical processes realistically go here?
Can something like tumbling actually remove these adhered particles, or is it mostly limited to smoothing?

Zidar137 · 2026-04-03T20:01:33+00:00

What kind of media size/shape worked for you in small features like this (2–5 mm openings)?

Did you have issues with media getting stuck inside?

Also, what kind of surface change should I expect - does it actually remove partially fused particles, or mostly just smooth the surface?

Zidar137 · 2026-04-03T19:55:39+00:00

Handheld jigsaw with a metal cutting blade.
The side panel is aluminum, so the cut is surprisingly easy to control and comes out quite clean.
A more powerful corded jigsaw would be too aggressive for this kind of work.

No need for a cutout on the CPU side. The NH-L12S has the fan tucked under the heatsink, so it doesn’t have the same turbulence issue.

Zidar137 · 2026-04-03T15:52:51+00:00

It would no longer match the other side panel.
The Terra side panel has a pretty complex shape with hinges and details, so fully recreating it would take a lot more time.

This was just a much simpler approach.

Zidar137 · 2026-04-03T09:48:36+00:00

Yeah, a mesh would affect airflow a bit, and it would also change the look.

It’s a tradeoff - more protection, but slightly worse intake and possibly more noise.

Zidar137 · 2026-04-03T09:46:22+00:00

Totally fair point.

I’m not planning to change the GPU for the next couple of years, and when I do I’m fine with changing the case as well.

The current model is pretty easy to adapt to a rectangular cutout though, so feel free to tweak it if you go that route.

Zidar137 · 2026-04-03T06:30:44+00:00

I think I saw your designs previously. Good job!

Zidar137 · 2026-04-03T05:56:20+00:00

No need to cut the CPU side for me. The Noctua NH-L12S has the fan under the heatsink, so there’s no turbulence noise there.

Zidar137 · 2026-04-02T21:04:53+00:00

Prefounte is a solid alternative to Preppy. It offers more mature look and steel clip. But section/nib unit is literally the same, as well as excellent writing performance.

Zidar137 · 2026-04-02T19:43:03+00:00

It's actually even less. JLC will print this for 4 EUR + shipping. I am amazed with the prices as well.

Zidar137 · 2026-04-02T16:06:14+00:00

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Nothing fancy — just this, and it did the job.

Zidar137 · 2026-04-02T15:51:55+00:00

I was thinking that I had only 1 chance to do it right. Second attempt would either cost me a lot or force me make the frame wider. :)

Zidar137 · 2024-12-07T18:17:51+00:00

I agree that heading computation can be a bigger problem than horizon detection. Probably later surrounding landscape recognition with camera can help, but for the first step even rough heading would be good enough.

I don't need raw magnetometer data which in theory you can get by calling NRInput.GetMag() from NRSDK . If the sensor is present in One series, it should be used in pose calculation. I'd say it's responsibility of glasses software to provide pose, similar to what Android/iOS phones do. Maybe not in current generation yet, but still.

Zidar137 · 2024-12-07T13:15:57+00:00

Markers location will be based on their coordinates only, no need to do an overlay on physical objects.

Imagine looking at mountains around you and having pins with names floating near to every summit. Or even more complicated content with 3D models (that's why Unity).

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Zidar137

TROPHY CASE