Sac Filling Systems Vs. Filling Systems Without Sacs

[ChickenScratch]

Since I started using and shopping for FP's last year, I've been staying away from pens with sac filling systems because they are made of a soft (probably easily damaged) material and I suspect they might prove to be higher maintenance and more likely to be in need of professional repair than pens that don't use sacs.

 

Is there any truth in my impression? How long does a sac last before it should be replaced? Is it pretty easy to learn to do yourself? Is there an advantage to sac systems vs. non-sac systems? Are some sac systems more durable than others?

[Tylerjordan]

So you are right that Sacs are 'higher maintenance' than non-sac systems. Where non-sac systems allow you to unscrew the barrel and section and easily use a bulb to rinse the section/feed/nib and have direct access to wash out the barrel on a Sac pen you have to repeatedly fill and flush the sac with water (or pen flush) to clean it out. If you don't switch ink colours a lot then it is not that big of a deal. Button fillers are easier to clean since instead of operating a lever you're only having to press a button over and over again.

 

They are generally not damaged easily when used properly. They are rather thick (maybe 1/16" of rubber or maybe 1/32"?) and should last at least half a decade before they need replacing. You can buy sacs made from Rubber or Silicon and some rubber ones are 'thin-walled' but I don't know off-hand if they are more durable or less durable than each other.

 

They are incredibly easy to repair. http://www.richardspens.com/?page=ref/repair/sac_replacement.htm and cost about $2 a sac and 10 minutes of time.

 

 

The advantages and disadvantages are the above mentioned + the fact that using the full barrel of a pen (i.e. an eyedropper, piston filler, etc.) allows more ink.
Also, another 'advantage' of sorts is that sac pens are available in a bunch of variants and you can collect and use more pens if you open up to sac pens.

Edited August 22, 2014 by Tylerjordan

[wspohn]

Half a decade?? I have many pens that have sacs that have lasted half a century! You must be buying cheap modern pens if you think 5 years is a good sac life.

 

A pen with a sac is normally cheaper to repair than a fancy piston filler system, BTW.

[kidde]

Sacs tend to be very durable. Conservatively I'd say 15-20 years, while many aerometric "51" Parkers are on their original sac. Rubber/silicon/PVC all have +/-. Rubber will discolor celluloid (maybe) after decades.

Sacs don't need lube and have fewer moving parts to wear out. One trade off is ease of cleaning, but Estie Js help there with screw in nib unit. Not many modern pens with sacs, possibly because cartridges are so common. They seem to be what ushered out the sac era.

[Tylerjordan]

Half a decade?? I have many pens that have sacs that have lasted half a century! You must be buying cheap modern pens if you think 5 years is a good sac life.

 

A pen with a sac is normally cheaper to repair than a fancy piston filler system, BTW.

 

 

No I don't even use modern pens. I didn't want to over-guess the sac life since I didn't have first-hand experience and didn't have a source off-hand on sac life.

[ac12]

I give an ink sac 15+ years of life.

Having said that, I've opened up Esterbrook pens with original Esterbrook ink sack that were still soft and pliable 60+ years after the pen was made.

You could also get a bum sack that will fail a week after you start using it.

 

Button fillers are also sack pens. They just use a button mechanism rather than a lever.

Pnumatic pens such as Sheaffer Snorkel and Touchdown are also sack pens. They just use a pnumatic mechansim to fill the sack.

 

Regarding vintage pens, there are a bunch of other types of filling mechanisms that are as bad or worse to clean out than a sack filler.

The Parker Vacumatics are a PIA to clean. And no you CANNOT take it apart w/o the tools and knowledge of how to do it w/o damaging the pen. And filling and draining a vac is tedious.

The Parker Aerometric is just as hard to clean as any sack pen, maybe a bit more tedious.

 

Esterbrooks are probably the easiest sack pens to clean. You unscrew the nib, and you can use an ink syringe to shoot water into the sack to clean it fast. Then use a bulb syringe to flush the nib assembly.

 

Silicone sacks are supposed to be more durable that rubber sacks, and stand up to difficult inks better. But as in 'no free lunch' it has its own disadvantage. You can read about silicone sacks on vintagepens.com. For the length of time a rubber sack will last, I decided to pass on silicone sacks for resacking my pens.

 

Resacing is NOT difficult for most pens. There are some tricky ones that are best left to the pros. The dangerous part of resacking a pen is removing the section from the barrel. That is where you can damage the pen (I damaged 2 pens). So the less you go into the pen the better. If you only have a couple sack pens, send it out. The cost of equipment/supplies is not worth it for 1 or 2 pens.

 

So IMHO, there is no reason to avoid a sack pen.

 

BTW, I use 3 sac pens on a regular basis; 2 Esterbrook LJs and a Sheaffer Touchdown desk pen.

Edited August 22, 2014 by ac12

[Ernst Bitterman]

There's trade-offs. Flexible-reservoir pens require more comprehensive maintenance when the matter comes up, but they don't need much attention between times. The Wahl Oxford desk pen (made about 1935) I've currently got at work needed a resac when I got it, but apart from rinsing it out after it's had its run of use, that's all it needs. So long as the inks aren't abusive, I think 15 years is a pretty good estimate for span between invasive care. Piston fillers, on the other hand, may need re-lubrication as frequently as yearly!

 

It's also a lot less trouble if something goes wrong with the mechanism in a sac-based pen (usually; twist-fillers, Vacumatics and Ink-Vues have special needs) than the other sort. Fewer specialized tools to break in, fewer parts to worry about. It is quite easy to do for yourself, too, and the cost of parts isn't so much of an impediment. Most people stumble at the shellac, which is readily available in quantities sufficient to refinish an end-table-- vast oceans of it, in other words, compared to the need to secure a sac, and unless that end-table needs looking at too, it's hard to swallow spending $5 or $10 on a tin that will mostly go to waste.

[tonybelding]

Do keep in mind that some modern-day inks will degrade latex rubber and shorten the service life greatly. I just got through sending a couple of bulb-fillers back to Edison to have the melted rubber replaced. Private Reserve Invincible Black was a likely culprit, although Noodler's is also suspect.

[Bo Bo Olson]

Depends on where you get the sac from. White factory, the original factory that made your normal last 30-40 years rubber sac's.

 

I had one last 62 years...due to the lever on my Esterbrook, knew it was from '48-52, and was in German hands, in drawers for 30 of it's last years before I got it. The sac lasted 2 years good and died real slow the last two.

 

White factory got started again some 6-7 years ago, if it's still there, they said they could make original sacs.

Be rather low amounts made due to lack of major pen companies making sac pens.

 

If the factory died, you sac's more than likely come from China and will not last as long. In fact I've heard of many sac's not lasting more than a few years.

Could be super saturated inks killed them, also.

Check the Esterbrook sub section for more info.

 

P-51 sacs are some sort fiberglass and don't count for rubber. Still going strong 70+ years later.

Edited August 22, 2014 by Bo Bo Olson

[KBeezie]

Do keep in mind that some modern-day inks will degrade latex rubber and shorten the service life greatly. I just got through sending a couple of bulb-fillers back to Edison to have the melted rubber replaced. Private Reserve Invincible Black was a likely culprit, although Noodler's is also suspect.

 

You don't remember which exact ink you put in it? (since you mentioned both PR and Noodler's just like Greg Minuskin did when bashing both companies as being the culprit to melted sacs). Though least you did mention one specific model of ink where as he won't even say which is suspect just black-labels the whole brand.

 

The culprit if it happened is more likely the fault of the sac if it came from a bad batch than the ink when it comes to the whole PR/Noodler's in Vintage pens fiasco.

 

http://ravensmarch.wordpress.com/2010/08/17/al-dente/

 

...

I prefer an alternative explanation offered by one of my fellow inmates at the Fountain Pen Network– a bad sac. Once in a while, the ingredients in a batch of sac rubber aren’t quite right, and it goes funny. There was a large batch some years ago that shocked the pen world with its sudden failure. It is likely that I got one in a similar state. I’ve had a look at some other pens with the same filler mechanism which I resacked about the same time, and there’s no evidence of failure there.

...

To sum up then: Noodler’s inks do not cook sacs. No matter how mushy the sac may be, look elsewhere for your culprit.

 

in that same vein though, in terms of noodler's and private reserve I have used or still using the following in vintage pens.

 

Montblanc 225 (Piston, not a sac but 70s puts it in vintage) : Has been married to Noodler's Black Eel since I got it, they're prefer together for me.

Sheaffer Touchdown Admiral (Evergreen, ~'51-52) is currently filled with Noodler's Texas Live Oak.

Pilot Elite Mini w/ 18K Soft Fine from the 70s, currently filled with Noodler's Liberty's Elysium. While it's a C/C pen, the converter they come with like the Con-20 that is an opaque/black latex sac.

 

... just noticed I don't have that many vintage pens filled at the moment (going thru kind of a downscaling and de-inking phase right now). But I had Black Eel in my Snorkel Admiral since I got it until I emptied it out in the past week, and have used Liberty's Elysium and Texas Blue Steel in my Eversharp Skyline Demi.

 

In terms of getting sacs and such for my pens, I get them from FountainPenSac.com which produces their latex sacs in the united states off the same kind of machinery used to make the same sacs for vintage pens during their original existance. (designed/formulated to be of the same quality and material as what they originally used)

Edited August 22, 2014 by KBeezie

[Ron Z]

I wish that latex sacs lasted 15 years, but they don't. I have pens in my collection that I've had for close to 20 years, and not one has had a sac that has lasted that long. All have failed in the 5-10 year range without continuous use, and without the use of boutique inks. The latex formulations are different, and the many of the modern inks, the boutique inks in particular, can cause a latex sac to fail startlingly fast. There are options other than latex sacs available, but each comes with it's own difficulty. There are, as I noted in a blog post, no silver bullets. Not all of the modern manufacturers are willing to buy the better grade sacs either....

 

Having said that, there is something special about using a vintage pen VS a modern one.

[tonybelding]

The rubber sacs were whatever Brian Gray uses, and I trust he has sourced them with due care.

 

I went back through my journals to try and determine the most likely ink that could have caused the damage. I used a number of different inks in those pens, and I didn't always make a note when I inked a pen, so I can't be completely sure. I do know that I used PR Invincible Black in both of those pens (it was my favorite black until PR reformulated it), and I know that I used multiple Noodler's colors in them.

 

I had a discussion with Brian Gray about this, and he said since he started shipping out more pens with rubber sacs (particularly the Menlo with its pump diaphragm), he's seen a trend of them coming back melted, usually after being used with PR or Noodler's (more often with Noodler's, but that probably reflects its much greater popularity).

 

I have a pen-pal who uses mostly Noodler's, and he's had to do multiple sac replacements in his Snorkel. After all while these experiences begin to add up.

 

Having said that... I also have sac pens that I've used Noodler's in, and they are still OK. I once had a gray Snorkel inked with Noodler's Black for a solid month, and there were no apparent ill effects. Maybe not all of the formulations and colors do it. Maybe there's still something else going on that we haven't figured out, I dunno.

 

I've had so many varied problems with so many PR inks that I don't plan to buy any more of those. I have plenty of modern pens with no rubber sacs that I can use Noodler's ink in, and I'm sure I'll continue to use a lot of it. For the sac pens, I'm giving Diamine and Herbin a spin.

[KBeezie]

The only problem is, I've yet to see anyone who could scientifically reproduce the issue. IF the sacs that are being melted comes from one source (ie: whoever Brian Gray is getting them from), then it would be rather easy to determine if it's the ink or the sacs by taking a piece of sac from another source and exposing it to the same ink. IF only one of the sacs melts or becomes all gooey then it's more likely there's a formulation issue with the sac than with the pen, especially if the only one having an impact is from that one source.

 

If they did so on most latex/rubber sacs from multiple providers we'd hear a lot more about it, especially with modern pens using squeeze fillers.

Edited August 23, 2014 by KBeezie

[ChickenScratch]

Thanks for the input, everyone! Lots of good info here. I ask these questions because I've come across quite a few vintage pens on eBay and elsewhere that are in my (modest) price range that I am tempted to buy, but their sac filling systems gave me pause. From the comments on here, it sounds like sacs last quite a long time, so they are not the headache I was expecting them to be. And it's good to know that Esterbrooks are among the easier sac pens to maintain, because a good many of the pens I'm interested in are Esties. All my pens right now are the cartridge/piston converter type, and it would be nice to have at least one pen with a larger ink capacity which sac pens seem to offer.

[WaskiSquirrel]

Pa Squirrel has two Parker 51s that he purchased in the late 1950s. They are both the aerometric type and the original sac works just fine in both.

 

What disappointed me was that it turned out I don't like the 51. More to the point, I found them difficult to clean. At the time, I was comparing them to my own Parker Vector with a converter. It cleaned easily. They took multiple flushings.

 

I've been interested in some of the Edison pens with the alternate filling mechanisms. I don't know if the latex is the culprit or if the ink is the culprit. Since I love Noodler's ink and am getting interested in Private Reserve, I decided to focus on pens where there are no known issues.

[tonybelding]

I've been interested in some of the Edison pens with the alternate filling mechanisms. I don't know if the latex is the culprit or if the ink is the culprit. Since I love Noodler's ink and am getting interested in Private Reserve, I decided to focus on pens where there are no known issues.

 

When it comes to Private Reserve, I've seen it all: bottles that came sealed from the factory with mold in them, over-saturated inks that don't flow right, melted rubber, corroded metal parts, ink that was extremely difficult to clean out of a pen. When I look at the vast array of ink brands available today that don't do those things, I wonder why I kept trying with PR for so long.

 

Maybe it's because the old PR Invincible Black really was so outstanding. But they don't even make that anymore, so... I'm out.

 

Meanwhile, I've got the bulb-fillers back now and inked with Diamine Eclipse and Asa Blue, which I find I rather like.

[KBeezie]

Pa Squirrel has two Parker 51s that he purchased in the late 1950s. They are both the aerometric type and the original sac works just fine in both.

 

What disappointed me was that it turned out I don't like the 51. More to the point, I found them difficult to clean. At the time, I was comparing them to my own Parker Vector with a converter. It cleaned easily. They took multiple flushings.

 

I've been interested in some of the Edison pens with the alternate filling mechanisms. I don't know if the latex is the culprit or if the ink is the culprit. Since I love Noodler's ink and am getting interested in Private Reserve, I decided to focus on pens where there are no known issues.

 

You should try flushing a Parker 51 Vac.