My wife decided that if I could purchase vintage pens and refurb them myself, I'd spend less money on pens over all (I didn't bother to explain I'd just buy more pens ), so she decided to purchase a "fixer upper" for me off eBay.

So, the pen in question is an "Onward" pen ... of some sort. It's a lever filler, and the sac was absolutely trashed. I've removed the sac (removing the section was a sphincter puckering event), and cleaned out the fragments from the barrel. How do I tell what size sac fits into the pen?

Click to view attachment

I've checked to make sure the lever is good, as is the brass wrap around bar inside the body of the pen itself. The nib is in excellent condition as well. So it's just the sac replacement ... and is there anything I can do about the slight brassing on the clip/lever?

The black barrel Parker 51 is just for size reference

If you have an assortment of sacs on hand, or some sac-fillers whose sections aren't hard to remove, then one rule of thumb you could use is to find out what size sac is an easy slip-fit into the barrel, and go down a size from there (the extra airspace provides some isolation from the warmth of your hand on the barrel).

-- Brian

I don't have sacs on hand ... this is my first sac replacement. Most of my other pens are C/C. The Parker 51 is an exception, but I'd rather not mess with that one.

Hi,

One approach would be to use the formula published by the Pen Sac Company: measure the inside diameter of the barrel in inches, and then multiply that figure by 50. The resulting number should be the proper sac size. The example given at the site is an inside diameter of .40 inches; multiplied by 50, the result is 20: a #20 sac.

Please note that this is technically the formula for Sheaffer pens; it's the one the Pen Sac Company recommends for pens made by companies other than the so-called "Big Four" companies. Your Onward would fall into that category.

Of course, no formula is ever 100% fool-proof; so you might want to calculate the correct sac size, and then "bracket" that size by ordering sacs one size smaller and one size larger. Then test them out and go with the best-fitting sac, keeping in mind Tweel's excellent advice. If you're planning to continue resacing pens, the extra sacs won't go to waste.

Good luck!

Jon

Belan,

I'll be willing to bet a #16 will fit. #14/#16/#18 fit probably 90% of the pens in the 'wild', with 70% taking a #16 or larger.

I have ordered sacs from:

http://www.simcom.on.ca/woodbin/ "Wood Bin"

http://www.tryphon.it/ "Tryphon"

http://www.pensacs.com/ "Pen Sac Company"

Good luck,

Ron

tryphon and pendemonium sell an assortment.

for your first sac, tighter is better.

Good suggestions, guys!

As far as the type of sacs ... any real advantage of silicon over latex? I notice that the Woodbin also has talc and shellac, too ... I'll get me some o' that, as well!

I'll do the measurements to be sure, and order at least 1 x 14, 16 and 18 (any chances of destroying a sac while trying to put it on?) ... probably non-tapered, I'm guessing?

Hi,

Absolutely, you'll need the shellac and the talc. You might also consider some section pliers - that tool might make the next section removal less worrisome. You'll want an implement to help remove the petrified latex and old shellac from the section nipple; I use a dental scraper, but a hobby knife would also probably work just fine.

I use silicone sacs only in pens that are at risk for future discoloration - black and pearl or jade celluloids, for example. Otherwise, I typically stick to latex. I would choose latex for this pen, but others may have different opinions.

And yes, I would order multiple sacs. It is certainly possible to mess up a sac, and besides, who needs the extra stress of knowing that there isn't a backup if something goes wrong?

Cheers,

Jon

You know, I was admiring your pen, and I think I'd go with silicone. The advantage is that it isn't vulcanized like latex, and so won't emit sulfur compounds that can discolor celluloid.


There's not a great chance of ripping the sac, unless you're using a tool with a strong spring that might get away from you. And a straight sac is what you want.

-- Brian

Once I learned hot to put a sac on w/o a sac spreader (the second pen I re-saced), I never used one again. I really thing they are made more to sell than to use.

Ron

I think I'll go ahead and order a couple of spare sacs, too. I'll be doing some more sac replacements, so it won't hurt to have extras on hand I'll probably skip on the sac spreader, too ... there seems to be a couple tricks for getting the sac in place without too much effort

Hi,

A good decision, I think, to forego the sac spreader. For me (others may disagree), this is one of those tools that actually makes a task harder to perform. I occasionally use mine to stretch the mouth of the sac a bit prior to resacing, but that's the only utility I see in the gizmo.

If not for the fact that the sac spreader was apparently standard issue among factory pen technicians back in the day, I would suspect it of being nothing more than a monstrous practical joke. Maybe if I could see historical footage of some experienced tech using the thing, I'd be able to figure it out.

Cheers,

Jon