I have received my TWSBI Vac Mini, and thought there maybe people waiting to see/hear about the Vac Mini before they make their decision on their order, so I have done a few photo comparisons of a few TWSBI pens.
The biggest thing I was anxious to know about the Vac Mini was if it has swappable nib unit with TWSBI Mini and TWSBI 580 pens. And the answer is, Yes! The nib units are swappable, after you take off the little metal ring. TWSBI Mini has a kind of a one-piece skirt that goes around the nib unit which pops off. TWSBI 580 has a metal ring plus a plastic skirt that also pop off. So just get the nib units to their bare components of nib, feed, and the black plastic nib casing (I call this the nib unit), and the three pens' nib units can be swapped around easily. The actual plastic nib casing material is slightly different in the new Vac Mini in that the material feels matt and not as smooth and shiny as the materials used for the TWSBI Mini and 580 nib casing. The lip of the Vac Mini nib casing is more angular and thicker too. Also compared to how tightly the nib and feed were squeezed into the nib casing in TWSBI Mini, it is much easier to just pull out the nib and feed from the Vac Mini nib casing, but the fit is not as loose as it was with TWSBI Eco. (Note: the first time you take off the nib unit from Vac Mini, you may need to get a grippy material to grab the area of the metal ring close to the nib, and use the unscrewing motion to get it off. It was fairly tightly screwed in.)
The nib size (as in the diameter at the base of the feed) is still the same modern #5. Vac Mini has the exact same nib shape and size as TWSBI Mini and TWSBI Eco, but nibs for TWSBI 580 will also fit Vac Mini fine, because they all share the same #5 feed diameter. This is all great news to me as I have quite a few Franken TWSBI nib units that I put together with vintage nibs and TWSBI nib unit, so I am able to swap the nib units around very easily.
Size of the pen itself is much more manageable that the Vac 700, it's only slightly longer than TWSBI Mini. I am also very happy to see that the clip is polished and shiny just like the TWSBI Mini and 580 pens. None of the ugly matt whitish metal on the Vac 700. Overall I am loving this little pen. Especially if you have already invested in a few different size nibs in TWSBI, it is great for swapping and playing. Have fun and enjoy!!!
TWSBI Vac Mini (Left) and TWSBI Mini (Right)
L to R. TWSBI Vac 700, Vac Mini, TWSBI Mini, and TWSBI 580 (Red)
Caps of TWSBI Vac Mini (Left) and TWSBI Mini (Right)
Section and nib units on TWSBI Vac Mini (Left) and TWSBI Mini (Right)
Nib units taken off on TWSBI Vac Mini (Left) and TWSBI Mini (Right)
Section and Nib Units disassembled on TWSBI Vac Mini (Left) and TWSBI Mini (Right)
Swapped! TWSBI Vac Mini with TWSBI Mini's nib unit installed (Left), and TWSBI Mini with Vac Mini's nib unit installed (Right)
TWSBI Vac Mini with Franken nib unit using a vintage Swan 3H gold nib. Ink is Blackstone Barrier Reef Blue in the Vac 20A Ink Bottle (Blue)