Ahoy!

I'm not interested much in the art involved in penturning, but I am quite interested in the technology. I've been working on a couple filling system ideas I have, but with crude materials; mostly stuff from the hardware store as well as cannibalized syringes, etc. Nothing wrong with that per se, but I'd like to move into something a little less kludgey.

Toward the end of making something new, I've been working on the systems that are or were once widespread- the first hack I made was a "replacement barrel" for a Kaweco Sport section out of a 3 mL syringe, with the plastic piston rod replaced by a metal rod and a metal knob with the needed female threading. I know, ink + metal = bad idea, but like I said, hardware store. I've no idea where one gets more appropriate parts, without being completely ready-made, which isn't any fun and won't further the implementation of my filler ideas.

With a few revisions of the piston idea done for now, I'd like to try making a vac filler. Not an entire pen, so many considerations are tossed out the window; really, little more than a vacuum filling tube with a nib glued into one end. Unlike the piston filler, I don't really have a starting point for parts, not without using the innards of Sheaffer Vac-Fil, getting a tube the same size, etc. Again- no fun!

I have the barrel down (for now). The packing is covered for now, but will require more work. What I need some parts for is the actual plunger. I've tried using some plastic washers from the hardware store but I can't find anything flexible enough. Perhaps I need a plunger that takes the cup shape by default, rather than simply being circular and forced into the cup shape by the bit under it?

Anyway, enough rambling- input or ideas on what I need and how I could make/get it would be appreciated. Thanks!

Regards,
Aaron

1) You could have used nylon bolts and nuts instead of metal ones, and remained "all-plastic", and those are usually available at hardware stores.

2) Why not one of them silicone cooking mats/handholders? You could get one of the gloves, which is molded into various complex curves, and cut a bit out of it, which ought to give you a cupped shape. You could cut out a neat circle by using a hole punch from a grommet kit, available at most hardware stores.

-George

Note the piston seal has to be very accurate in external & hole diameter
The hole has to be exactly in the center.
A slight eccentric offset of 0.1/0.2mm will already create filling efficiency problems.
Given these facts one should use a dedicated "twin-punch", featuring a hole punch which is perfectly centered in the outer punch. This guarantees that all seals will be perfect.
Francis