Duofold Af, Is This Pressure Bar Okay?

[Flounder]

I picked up a nice British Duofold AF at auction, needing "cleaning etc." It doesn't fill. It's had a good soak for a couple of days to clear out the old ink, and I figured it was due a new sac. I followed an old post of Oxonian's in heating the BHR section and unscrewing the barrel rather than try unscrewing the button unit from the top.

 

To my surprise, the sac, though a little stiff, is still pliant enough to fill manually. Is the culprit here the pressure bar? It seems too short to wedge between the bottom of the sac nipple and the top of the extended button. Also, there's a big gap between the start of the top bend in the flexing strip and the rigid piece that pushes against the sac. The only experience I have with pressure bars was jerry rigging a Hero 616 to button fill, a pressure bar with a similar gap didn't seem to bend in the right way.

 

[edit - I doubt this is relevant, but upon opening the barrel, there was the most extraordinary smell of toothpaste.]

 

 

 

http://i773.photobucket.com/albums/yy19/flounder2009/Duofold%20AF/th_DAF00.jpg

http://i773.photobucket.com/albums/yy19/flounder2009/Duofold%20AF/th_DAF006.jpg

Edited January 18, 2012 by Flounder

[Tom Heath]

I have only done a few of these , here in Pa, USA

One just rather recently.

I bought the pen as a parts pen, it came to me in pieces but , all parts in one bag.

 

I tried assembling the front end 1st then tucking in the pressure bar from the back and had trouble with the rear screw in nut with button trying to turn the bar which in turn would spin the sac, not good

 

Next I looked inside to see if there was a ledge which the pressure bar would sit on...

 

Then I put a smaller sized sac on the back of the section perhaps a #16 sac, made sure the same was at least 1/4" shorter than would fit length wise.. with enough room to allow the sac to turn with the threaded section, applied talic to the sac, the unit installed quickly and filled nicely...

 

As I recall I tucked the rear end of the pressure bar into the button and observed that on my pen it came into the lower threaded area by about two thread widths.. I don't know if there is a prescribed length for the pressure bar. If this doesn't work for you you may need to lengthen it a bit.

 

Without a factory repair manual and or knowing this is the original pressure bar, sometimes you will need to ad lib a bit.

Good Luck

 

These pens can be fun writers.

Tom

[flighter51]

I have had this problem before with odd button fillers. My solution is to rip a bit of white fluff off a cotton swab, make a tiny ball and place it in the button and keep adding little bits until the fill unit clicks when pressed after reassembly. Obviously removal of the sac makes this repair easier as you aren't fussing with it while getting the pressure bar to work. It is also completely reversible.

 

Fluff is cheaper than a new pressure bar.

 

I hope this is helpful.

 

 

Happy pen hunting,

 

fern

[Flounder]

Wouldn't the fluff compress with use though? Hmm. I think I'll fit a new pressure bar as well as fit a sac. I just don't get how this could have worked in the first place?

[flighter51]

The fluff does compress which allows you by increments get to the point where the bar is flexing properly and you get that satisfying click sound (sans sac of course). It actually is a repair tip I picked up from disassembly of Dutch button filling pen years ago.

 

Replacing the pressure bar is preferred of course, but in a pinch I can tell you this works.

 

 

Happy pen hunting,

 

fern

[Flounder]

flighter51, if it didn't come across right, I was trying to say I don't get how this pressure bar could have ever worked, being so short. I wasn't disparaging your tip about the fluff.

[flighter51]

No, I apologize if I offended in any way. I did not take your reply as anything other than wondering if this repair would work over time. Email can lead to misunderstandings and I apologize sincerely if my 'tone' engendered any offense. I just get excited about repairs. I love repairs. Danny Fudge and I have more fun talking about some of the repairs we try. I spend hours at his repair table discussing pen repair tips when we see each other at shows, hopefully he is coming back to Little Rock in March.

 

I love that you are going to get that pen in tip top shape. It looks fantastic.

 

fern

[Flounder]

Well, its been a few days since I finally fitted the new bar and ink sac. The Duofold is shaping up to be a nice wee writer

 

http://i773.photobucket.com/albums/yy19/flounder2009/Duofold%20AF/th_NiceDAF001Large.jpg

 

I found that the captive button can actually make installing a new bar without twisting up the new ink sac very easy! With a normal button, the top of the pressure bar is quite loose without modification:

 

 

 

http://i773.photobucket.com/albums/yy19/flounder2009/Duofold%20AF/th_rebar002Medium.jpg

 

The AF's captive button seems to be a slightly smaller internal diameter.

 

http://i773.photobucket.com/albums/yy19/flounder2009/Duofold%20AF/th_rebar003Medium.jpg

 

If the curved top section of the pressure bar (MSPainted in green) is slotted into the button, it lodges firmly and the pressure bar will rotate around the barrel with the button. The bottom end still needs trimming down a little and smoothing, mind.

 

http://i773.photobucket.com/albums/yy19/flounder2009/Duofold%20AF/th_rebar005Medium.jpg

 

 

 

If you screw the section into the barrel a little, then rotate the button a little, and so on, the pressure bar stays straight, and can't twist up the ink sac as you reassemble the pen

[PDW]

ISTR that Marshall and Oldfield recommend using a narrower sac than usual if you can't get the aluminium button assembly out, to prevent the sac twisting on reassembly with the pressure bar already in place. I've a feeling (I'm at work and the book's at home) that M+O didn't say how small you should go, and as my AF arrived this morning I'd be grateful for a little advice - would a #16 do?

[Ron Z]

You can use a Vac wrench to unscrew the button assembly. The threads are the same size. You can also close down the top of the pressure bar a bit so that it fits into the button more easily. They are usually spread out a little more than you want.

[Flounder]

I did use a size 16 sac after measuring the ink sac nipple, though I've always struggled tremendously with maths so PDW you'd best check your own to be safe. I did think it was a little thinner than the one it replaced, as it happens. The AF has become one of my favourite writers, hope your brings you as much joy to use!

 

[edit - something peculiar is going on, I can't insert hyperlinks. Here's the thread I was trying to figure out the sac size in]:

 

www.fountainpennetwork.com/forum/index.php?/topic/213328-hells-hounds-i-hate-maths/

Edited February 29, 2012 by Flounder

[my63]

Hi Flounder

Would you mind sharing your supplier of pressure bars and sacs.

I have two parkers needing replacement pressure bars and three needing sacs.

Unfortunatley my previous supplier is no longer responding.

Thanks

Michael

[PDW]

I did use a size 16 sac after measuring the ink sac nipple, though I've always struggled tremendously with maths so PDW you'd best check your own to be safe. I did think it was a little thinner than the one it replaced, as it happens. The AF has become one of my favourite writers, hope your brings you as much joy to use!

 

 

I couldn't stop myself from resacing it before I read your response. I used a sac which fitted with a little free space in the barrel with the pressure bar fitted. I suspect that it's about one size down from the 'correct' one (I probably used a 16 but didn't measure it when it came out of my box of sacs). I've a feeling that the ink capacity is not all it could be, but it went back together and it works. Now looking forward to giving it a test drive.

[Flounder]

Hi Michael, I usually get my ink sacs from cathedral pens, but there are quite a few British suppliers, and I got the pressure bar from eBay seller chillipea. They have them in two sizes, I got the 6.8 cm size and trimmed it down for the AF.

 

I did measure the capacity after fitting the size 16 sac, and it was about the same as my Sheaffer Snorkel's. Maybe a necked sac might give more capacity?

 

 

[Flounder]

I thought I'd resurrect this thread, as I had to open up the pen to replace the BHR section, which had a split. To increase the capacity, I fit a size 17 sac, which was still pretty tight on the the nipple, and still slim enough to fit the pressure bar using the above method without trouble.  

[hari317]

 

I did measure the capacity after fitting the size 16 sac, and it was about the same as my Sheaffer Snorkel's. Maybe a necked sac might give more capacity?

 

I measured my Duofold AF's ink capacity and I get only 0.4 to 0.5ml approximately. Do you remember how much you got out of your example?

 

BTW nice useful thread, thanks!

[Flounder]

Hi Hari, that seems very low. With the standard size 17 sac, which I have just tested with ink, my AF gets 0.92 ml. The beautiful stubbish nib gets through that quite fast, the AF is still my favourite writer so it is always in use.

 

edit - measured by expelling the ink from the pen using the press button, into an empty beaker, then pulling it up a 1ml syringe. I don't have digital scales!

Edited April 23, 2013 by Flounder

[hari317]

Flounder, thanks! My ebay pen is more than a couple years old and still with the same sac that came in it. I reinked the pen today on a whim. Time to put in a proper sized sac then.

[hari317]

Ok. I resaced the pen. the sac in it was all twisted. and the p[ressure bar had also got bent. I had to repair the present pressure bar since I had no spares at hand. I was able to remove(wiggle) the button without unscrewing the threaded button holder from the barrel. I resaced with a 17-1/2 N necked sac from the pen sac co. Now I get a 1ml water fill measured using a digital scale. Still lesser than the potential sac volume but maybe due to a less efficient repaired pressure bar. Thanks! Hari

[Flounder]

Sounds good Hari! If this standard style 17 sac fails, I might follow your example. 1ml is probably the magic number anyway, quite basic feeds in these AFs.