Jowo 6 Nib Unit | Sengbusch | #4 Dipaday | 14kt Gold | Fine Super Flex

🥇 Grade: B
🏠 Housing: Nikko Red Ebonite, JOWO #6
🔱 Nib: Sengbusch Dipaday 14 KT 4
🖋️ Line Spec: F – 4B | 0.35mm V / 0.30mm H – 1.52mm (5.07x)
🌡️ Flexibility Pressure: 320g Super Flex
📐 Dimensions: 22.00mm nib length past housing
⚖️ Weight: 1.941g

Superb flex, smooth, with a very consistent juicy flow. Unflexed it's a fine line, 0.30mm on the cross stroke and 0.35mm down, and moderate pressure opens the tines to a 4B at 1.52mm, about 5x off the hairline. The swell comes on evenly through the whole range and the feed kept up across two full rows of flourish drills without thinning. Exceptional writing experience, and I don't say that about many #4 nibs.

The imprint reads SENGBUSCH with Dipaday in script under it and a 4 for the size. This is a desk pen nib. The Sengbusch Self-Closing Inkstand Company of Milwaukee, Wisconsin got going around 1905 on Gustav Sengbusch's 1902 patents for an inkwell that closed itself when you pulled the pen out, and the Dipaday was their desk pen for those stands in the 1930s, advertised as "not a fountain pen" (one dip in the stand was the whole idea). Not much else is documented on the nibs themselves.

I've rated this B, light wear from use, imprint crisp, tines original and even. I heat-set it to a Nikko ebonite feed in the red Nikko ebonite JOWO #6 housing, aligned the tines, smoothed and tuned the tipping, and lightly polished the stains off the gold, leaving the micro scratches alone so the gold keeps its thickness, then wrote it in as a complete unit.

Tested on Tomoe River 68gsm White with Pelikan 4001 Brilliant Black.

One note on filling. A vintage nib unit runs best behind a piston, a sac, or a lightly pressurized eyedropper chamber, since those keep enough ink moving into the feed, and a latex or silicone sac is ideal. Modern cartridge converters don't build enough air pressure to supply the feed consistently, so with a converter expect to prime the feed to keep the flow smooth through flourishes.