Proper Sac For Eversharp Doric Desk Pen?

July 21, 2016

Hello everyone,

I recently picked up an absolutely mint W-E Doric desk pen (in Cashmere, of all places) and was wondering what the correct sac size for it was. It has a #5 adjustable nib and the nipple appears to be slightly more than 1/4" across. I've seen conflicting info from several sources on which size sac to use: Richard Binder's website cites the proper size as 17 or 18 (not quite sure if my pen qualifies as a Doric or a Personal Point) while some other sites give the proper size as 22 (which seems way too big). On a similar note, should I use a regular latex sac or a silicone sac to protect the celluloid (it's a grey-black color and I am unsure if it is prone to discoloration)?

Thanks for the help!

July 21, 2016

There are different size Dorics, so the sac size will vary.

The proper way to determine sac size if you aren't sure is to measure using a dial caliper. General makes a plastic one with a scale that is divided in 64ths of an inch. I've seen it at Lowes, Home Deopt and on eBay, but there are others that make them.

Sacs are measured in 64ths of an inch. Measure the diameter of the sac nipple with all of the old sac cleaned off of it. If for instance you measure 17/64" you need a #17 sac, but could use a #16. Woodbin only sells the even numbered sacs, Pen Sac Co sells odd and even numbers, so you get much closer to the right size.

July 22, 2016

Thanks for the heads up...I think I know a guy from whom I can borrow some dial calipers.

July 23, 2016

Hello everyone,

I recently picked up an absolutely mint W-E Doric desk pen (in Cashmere, of all places) ...
On a similar note, should I use a regular latex sac or a silicone sac to protect the celluloid (it's a grey-black color and I am unsure if it is prone to discoloration)?

Thanks for the help!

I had this discussion with David Nishimura. For a DESK pen you do NOT want to use a silicone sac. The reason is that silicone is air permeable. What this means is that the air will slowly go through the sac, into the space above the ink, and your ink will start to slowly drip into the holder. I have not put a silicone sac onto desk pen so I can't say how fast/slow the ink will drip, probably rather slowly. But even a drop a day will gradually drain the pen and fill the holder with ink...YUK that could be MESSY.

For a clip pen that is kept nib UP, there is no air in the back of the ink, because the ink is at the back of the sac when the pen is nib UP. So this issue does not apply. Plus the nib is UP, so the ink cannot drip UP into the cap against gravity.

So the conclusion we came to was to use latex sacs in desk pens.

If you do not intend to use the pen, just remove the old sac, and leave the pen sac-less. This is what I do with some of my collection pen. No sac = no off-gasing to discolor the celluloid.

July 25, 2016

silicone is air permeable

Wow, I did not know that! I certainly intend to use it, and having it fully functional would help me if I ever were to sell it. Thanks for that piece of knowledge; I guess I'll use latex.

July 25, 2016

I should have this pinned - take a look at this article....

July 26, 2016

I should have this pinned - take a look at this article....

Very interesting read! I've also read some things about silicone sacs having durability issues...

July 27, 2016

I picked up a Doric desk pen myself, but it's a mess - broken through and glued together. The nib's a mess too...a #3 Adjustable with the slider gone, but it's better than what I have in my ringtop Doric at the moment, so in it'll go.

August 8, 2016

Update: I measured the nipple and it came in at 17/64" and I am glad to say that the size 17 sac I ordered fits like a glove! Will have the pen back together shortly.