Hi,

In April I got a beautiful black aerometric Parker 51 (made in England so date stamped with 1958). It is the best writer I have, smoothest and perfect ink flow. The pen itself works perfectly but I think it has had its ink sac replaced at some point because it seems to be black, like the inner tube of a bike tyre, and smells very strongly of rubber (I can smell it as soon as the lid is taken off and I start writing!). It's my best writer so I forgive the smell! Though it is a bit frustrating that I can't tell how much ink is left. I have a Mk III Parker which has a clear ink sac. So, are original ink sacs of Mk I aerometrics clear?

Thanks

All the 51 Aeros had what Parker called a PlyGlass sac. Seems to be made from nylon and has outlasted even what Parker would have guessed. Replacement Plyglass sacs are not made that are correct for the 51 but you can find shorter sacs that would be correct for a 21. If your sac is black rubber it has been replaced. It is rare to need to replace a 51 sac but when I need to, I get one from a parts pen. If you look closely at your Mk III sac, you may be able to see ribs on the inner surface. I'm told these are there to break the surface tension of the ink.

As for clear, many of the correct sacs are ink stained to the point they are black, even after cleaning. The staining doesn't seem to be a problem.

Todd

Hi,

Thanks for the reply. I think mine has been replaced, as my MK III sac has a smooth surface, whereas my '58 aero has a more rubber like surface like a bike inner tube