Sheaffer Balance Os Vac-Fill Repair

[sanesan]

I've been fiddling around with a black Sheaffer OS vac-fill. I've successfully serviced several smaller balance and triumph vac-fills using the o-ring and closure washer method, but for this OS vac-fill, the standard closure washer isn't quite large enough. I currently drilled the packing unit out and fit the o-ring in, but because I haven't secured it in with MEK, it leaks from the back.

 

Does anyone else have any experience repairing Sheaffer OS vac-fills?

[silverlifter]

Does anyone else have any experience repairing Sheaffer OS vac-fills?

 

Gerry Berg is the person I would ask about this. He pops up here from time to time.

[Ron Z]

You do need to use some solvent to retain the washer. No surprise that it leaks. I make a slurry out dissolved celluloid, and use that to secure that retaining washer in the packing unit. The tool that I designed and gave to Dale Beebe (pentooling.com) (no, I don't get anything from the sales) makes inserting both the 0-ring and retaining washer much, much easier.

 

Is the 0-ring a snug fit, or is it loose too? Most of the pens used the same packing washers even though the threads on the packing unit are larger, so the retaining washer should fit if you used the right size drill. Having said that, some of the earlier pens, both WASP and Sheaffer, had screw in units (left hand thread) with a larger ID. It could be either of these things. I generally cut my own retaining washers out of the white 1/4" thick walled styrene tubing which raises a burr, and makes for a tighter fit.

 

IF that doesn't work, a spacer bushing may be needed to center and hold the 0-ring. This will involve some remedial lathe work, or replacing the packing unit if the hole is way oversize.

[sanesan]

Thank you for the advice, Ron.

 

The o-ring seems snug, and I drilled it in as deep as I could go. The diameter of the retaining washer only covers about 2/3 of the diameter of the barrel so perhaps it is one of the earlier screw in units. I'll have to purchase a styrene sheet and some punches.