Under Pressure

Pressure bars. Or, as some people call them, presser bars. I always thought that was a spelling mistake but… well… they press, so one’s as good as the other. If I’d been prepared to do this right, I would have had the full complement of pressure bars, of which there are many, but this is what I have. Conspicuously absent are the Swan Leverless angle bar and Parker’s anchor bar. The rest are really just variations on the theme of these three.

Exciting, aren’t they? Well, no, perhaps not, but for anyone interested in how their pen works, pressure bars aren’t entirely dull either. On the left is the slide bar, which you’ll find in most Conway Stewarts and some Watermans and Eversharps. In the middle is the j-bar which you’ll find in most other lever fillers, and on the right is a button bar for, as you’d expect, most button-fillers.

Slide bars are tricky to fit the first couple of times, then you have the knack of doing it. They slip onto lugs on the bottom of the lever and work very efficiently, because they descend completely flat on the sac. Sometimes these lugs can become flattened or break off, and it’s often suggested that a j-bar be substituted. Don’t do it! This is a bad repair. From a collector’s point of view, it makes the pen non-original. Practically – and more importantly – it can damage the pen. Waterman lever boxes have a tendency to break anyway, and if you add the stress of an inappropriate j-bar, the box is sure to crack. Similarly with Conway Stewart levers, which are notoriously fragile. They will deal with the resistance of a sac, but a sac and a piece of sprung metal is likely to prove too much. Certainly, there are Conway Stewarts that have j-bars – all Dinkies (so far as I know) 12s, 14s, 15s, 36s, 475s and 759s – but they were designed to resist the additional pressure. It’s far better, faced with a lever with broken lugs, to replace the lever. I know that’s a pain but you’ll thank me in the long run. Really. You will.

J-bars in their own place are absolutely fine, and many excellent pens use them. They might not be quite such efficient sac squeezers because the bend at the end can mean there’s an short length of sac that’s not fully compressed, but it’s marginal. They can suffer from metal fatigue and weaken or break and need to be replaced. The modern replacements you can buy, I find, are rather rigid and hard to flex. I don’t use them, but salvage j-bars from scrap pens. Try to find a j-bar as similar as possible to the broken one, and take care in lining it up.

Button bars are very efficient, because, again, they move parallel to the sac and squeeze it flat. In theory, all pens that use button bars should have screw-in sections to resist the downward pressure of operating the filling system. In practice, many are friction fit and none the worse for it. Obviously, if the joint between the section and barrel becomes too loose, this would be a problem, hence the glued sections we sometimes find. Friction fit is cheaper to make than threaded, so many go with it. Wishing to reduce costs by replacing threaded sections with friction ones, Parker developed its clever anchor bar, a three-piece pressure bar that hangs from the button opening and so applies no pressure on the section. It’s also very efficient in getting ink into the pen. You’ll find it on Televisors and some Duofolds.

Finally (for brevity!) there’s the Leverless angle bar, a sort of Neanderthal among pressure bars. It’s a non-springy hunk of metal that rotates and gathers up the sac, wrings it out and squashes it against the barrel wall. Efficiency of Leverlesses depends greatly on how well they’re re-sacced, and even a well-fettled Leverless will draw less ink than an equivalent lever-filler, but again, it’s at the margins.


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